initial work to split into dart_filament and flutter_filament

flutter_filament/windows/include/filament/utils/Allocator.h

@@ -0,0 +1,840 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_ALLOCATOR_H
+#define TNT_UTILS_ALLOCATOR_H
+
+
+#include <utils/compiler.h>
+#include <utils/debug.h>
+#include <utils/memalign.h>
+#include <utils/Mutex.h>
+#include <utils/SpinLock.h>
+
+#include <atomic>
+#include <cstddef>
+#include <mutex>
+#include <type_traits>
+
+#include <assert.h>
+#include <stdlib.h>
+
+namespace utils {
+
+namespace pointermath {
+
+template <typename P, typename T>
+static inline P* add(P* a, T b) noexcept {
+    return (P*)(uintptr_t(a) + uintptr_t(b));
+}
+
+template <typename P>
+static inline P* align(P* p, size_t alignment) noexcept {
+    // alignment must be a power-of-two
+    assert(alignment && !(alignment & alignment-1));
+    return (P*)((uintptr_t(p) + alignment - 1) & ~(alignment - 1));
+}
+
+template <typename P>
+static inline P* align(P* p, size_t alignment, size_t offset) noexcept {
+    P* const r = align(add(p, offset), alignment);
+    assert(r >= add(p, offset));
+    return r;
+}
+
+}
+
+/* ------------------------------------------------------------------------------------------------
+ * LinearAllocator
+ *
+ * + Allocates blocks linearly
+ * + Cannot free individual blocks
+ * + Can free top of memory back up to a specified point
+ * + Doesn't call destructors
+ * ------------------------------------------------------------------------------------------------
+ */
+
+class LinearAllocator {
+public:
+    // use memory area provided
+    LinearAllocator(void* begin, void* end) noexcept;
+
+    template <typename AREA>
+    explicit LinearAllocator(const AREA& area) : LinearAllocator(area.begin(), area.end()) { }
+
+    // Allocators can't be copied
+    LinearAllocator(const LinearAllocator& rhs) = delete;
+    LinearAllocator& operator=(const LinearAllocator& rhs) = delete;
+
+    // Allocators can be moved
+    LinearAllocator(LinearAllocator&& rhs) noexcept;
+    LinearAllocator& operator=(LinearAllocator&& rhs) noexcept;
+
+    ~LinearAllocator() noexcept = default;
+
+    // our allocator concept
+    void* alloc(size_t size, size_t alignment = alignof(std::max_align_t), size_t extra = 0) UTILS_RESTRICT {
+        // branch-less allocation
+        void* const p = pointermath::align(current(), alignment, extra);
+        void* const c = pointermath::add(p, size);
+        bool success = c <= end();
+        set_current(success ? c : current());
+        return success ? p : nullptr;
+    }
+
+    // API specific to this allocator
+
+    void *getCurrent() UTILS_RESTRICT noexcept {
+        return current();
+    }
+
+    // free memory back to the specified point
+    void rewind(void* p) UTILS_RESTRICT noexcept {
+        assert(p>=mBegin && p<end());
+        set_current(p);
+    }
+
+    // frees all allocated blocks
+    void reset() UTILS_RESTRICT noexcept {
+        rewind(mBegin);
+    }
+
+    size_t allocated() const UTILS_RESTRICT noexcept {
+        return mSize;
+    }
+
+    size_t available() const UTILS_RESTRICT noexcept {
+        return mSize - mCur;
+    }
+
+    void swap(LinearAllocator& rhs) noexcept;
+
+    void *base() noexcept { return mBegin; }
+
+    void free(void*, size_t) UTILS_RESTRICT noexcept { }
+
+private:
+    void* end() UTILS_RESTRICT noexcept { return pointermath::add(mBegin, mSize); }
+    void* current() UTILS_RESTRICT noexcept { return pointermath::add(mBegin, mCur); }
+    void set_current(void* p) UTILS_RESTRICT noexcept {
+        mCur = uint32_t(uintptr_t(p) - uintptr_t(mBegin));
+    }
+
+    void* mBegin = nullptr;
+    uint32_t mSize = 0;
+    uint32_t mCur = 0;
+};
+
+/* ------------------------------------------------------------------------------------------------
+ * HeapAllocator
+ *
+ * + uses malloc() for all allocations
+ * + frees blocks with free()
+ * ------------------------------------------------------------------------------------------------
+ */
+class HeapAllocator {
+public:
+    HeapAllocator() noexcept = default;
+
+    template <typename AREA>
+    explicit HeapAllocator(const AREA&) { }
+
+    // our allocator concept
+    void* alloc(size_t size, size_t alignment = alignof(std::max_align_t), size_t extra = 0) {
+        // this allocator doesn't support 'extra'
+        assert(extra == 0);
+        return aligned_alloc(size, alignment);
+    }
+
+    void free(void* p) noexcept {
+        aligned_free(p);
+    }
+
+    void free(void* p, size_t) noexcept {
+        this->free(p);
+    }
+
+    ~HeapAllocator() noexcept = default;
+
+    void swap(HeapAllocator&) noexcept { }
+};
+
+// ------------------------------------------------------------------------------------------------
+
+class FreeList {
+public:
+    FreeList() noexcept = default;
+    FreeList(void* begin, void* end, size_t elementSize, size_t alignment, size_t extra) noexcept;
+    FreeList(const FreeList& rhs) = delete;
+    FreeList& operator=(const FreeList& rhs) = delete;
+    FreeList(FreeList&& rhs) noexcept = default;
+    FreeList& operator=(FreeList&& rhs) noexcept = default;
+
+    void* pop() noexcept {
+        Node* const head = mHead;
+        mHead = head ? head->next : nullptr;
+        // this could indicate a use after free
+        assert(!mHead || mHead >= mBegin && mHead < mEnd);
+        return head;
+    }
+
+    void push(void* p) noexcept {
+        assert(p);
+        assert(p >= mBegin && p < mEnd);
+        // TODO: assert this is one of our pointer (i.e.: it's address match one of ours)
+        Node* const head = static_cast<Node*>(p);
+        head->next = mHead;
+        mHead = head;
+    }
+
+    void *getFirst() noexcept {
+        return mHead;
+    }
+
+private:
+    struct Node {
+        Node* next;
+    };
+
+    static Node* init(void* begin, void* end,
+            size_t elementSize, size_t alignment, size_t extra) noexcept;
+
+    Node* mHead = nullptr;
+
+#ifndef NDEBUG
+    // These are needed only for debugging...
+    void* mBegin = nullptr;
+    void* mEnd = nullptr;
+#endif
+};
+
+class AtomicFreeList {
+public:
+    AtomicFreeList() noexcept = default;
+    AtomicFreeList(void* begin, void* end,
+            size_t elementSize, size_t alignment, size_t extra) noexcept;
+    AtomicFreeList(const FreeList& rhs) = delete;
+    AtomicFreeList& operator=(const FreeList& rhs) = delete;
+
+    void* pop() noexcept {
+        Node* const storage = mStorage;
+
+        HeadPtr currentHead = mHead.load();
+        while (currentHead.offset >= 0) {
+            // The value of "next" we load here might already contain application data if another
+            // thread raced ahead of us. But in that case, the computed "newHead" will be discarded
+            // since compare_exchange_weak fails. Then this thread will loop with the updated
+            // value of currentHead, and try again.
+            Node* const next = storage[currentHead.offset].next.load(std::memory_order_relaxed);
+            const HeadPtr newHead{ next ? int32_t(next - storage) : -1, currentHead.tag + 1 };
+            // In the rare case that the other thread that raced ahead of us already returned the 
+            // same mHead we just loaded, but it now has a different "next" value, the tag field will not 
+            // match, and compare_exchange_weak will fail and prevent that particular race condition.
+            if (mHead.compare_exchange_weak(currentHead, newHead)) {
+                // This assert needs to occur after we have validated that there was no race condition
+                // Otherwise, next might already contain application data, if another thread
+                // raced ahead of us after we loaded mHead, but before we loaded mHead->next.
+                assert(!next || next >= storage);
+                break;
+            }
+        }
+        void* p = (currentHead.offset >= 0) ? (storage + currentHead.offset) : nullptr;
+        assert(!p || p >= storage);
+        return p;
+    }
+
+    void push(void* p) noexcept {
+        Node* const storage = mStorage;
+        assert(p && p >= storage);
+        Node* const node = static_cast<Node*>(p);
+        HeadPtr currentHead = mHead.load();
+        HeadPtr newHead = { int32_t(node - storage), currentHead.tag + 1 };
+        do {
+            newHead.tag = currentHead.tag + 1;
+            Node* const n = (currentHead.offset >= 0) ? (storage + currentHead.offset) : nullptr;
+            node->next.store(n, std::memory_order_relaxed);
+        } while(!mHead.compare_exchange_weak(currentHead, newHead));
+    }
+
+    void* getFirst() noexcept {
+        return mStorage + mHead.load(std::memory_order_relaxed).offset;
+    }
+
+private:
+    struct Node {
+        // This should be a regular (non-atomic) pointer, but this causes TSAN to complain
+        // about a data-race that exists but is benin. We always use this atomic<> in
+        // relaxed mode.
+        // The data race TSAN complains about is when a pop() is interrupted by a
+        // pop() + push() just after mHead->next is read -- it appears as though it is written
+        // without synchronization (by the push), however in that case, the pop's CAS will fail
+        // and things will auto-correct.
+        //
+        //    Pop()                       |
+        //     |                          |
+        //   read head->next              |
+        //     |                        pop()
+        //     |                          |
+        //     |                        read head->next
+        //     |                         CAS, tag++
+        //     |                          |
+        //     |                        push()
+        //     |                          |
+        // [TSAN: data-race here]       write head->next
+        //     |                         CAS, tag++
+        //    CAS fails
+        //     |
+        //   read head->next
+        //     |
+        //    CAS, tag++
+        //
+        std::atomic<Node*> next;
+    };
+
+    // This struct is using a 32-bit offset into the arena rather than
+    // a direct pointer, because together with the 32-bit tag, it needs to 
+    // fit into 8 bytes. If it was any larger, it would not be possible to
+    // access it atomically.
+    struct alignas(8) HeadPtr {
+        int32_t offset;
+        uint32_t tag;
+    };
+
+    std::atomic<HeadPtr> mHead{};
+
+    Node* mStorage = nullptr;
+};
+
+// ------------------------------------------------------------------------------------------------
+
+template <
+        size_t ELEMENT_SIZE,
+        size_t ALIGNMENT = alignof(std::max_align_t),
+        size_t OFFSET = 0,
+        typename FREELIST = FreeList>
+class PoolAllocator {
+    static_assert(ELEMENT_SIZE >= sizeof(void*), "ELEMENT_SIZE must accommodate at least a pointer");
+public:
+    // our allocator concept
+    void* alloc(size_t size = ELEMENT_SIZE,
+                size_t alignment = ALIGNMENT, size_t offset = OFFSET) noexcept {
+        assert(size <= ELEMENT_SIZE);
+        assert(alignment <= ALIGNMENT);
+        assert(offset == OFFSET);
+        return mFreeList.pop();
+    }
+
+    void free(void* p, size_t = ELEMENT_SIZE) noexcept {
+        mFreeList.push(p);
+    }
+
+    constexpr size_t getSize() const noexcept { return ELEMENT_SIZE; }
+
+    PoolAllocator(void* begin, void* end) noexcept
+        : mFreeList(begin, end, ELEMENT_SIZE, ALIGNMENT, OFFSET) {
+    }
+
+    template <typename AREA>
+    explicit PoolAllocator(const AREA& area) noexcept
+        : PoolAllocator(area.begin(), area.end()) {
+    }
+
+    // Allocators can't be copied
+    PoolAllocator(const PoolAllocator& rhs) = delete;
+    PoolAllocator& operator=(const PoolAllocator& rhs) = delete;
+
+    // Allocators can be moved
+    PoolAllocator(PoolAllocator&& rhs) = default;
+    PoolAllocator& operator=(PoolAllocator&& rhs) = default;
+
+    PoolAllocator() noexcept = default;
+    ~PoolAllocator() noexcept = default;
+
+    // API specific to this allocator
+
+    void *getCurrent() noexcept {
+        return mFreeList.getFirst();
+    }
+
+private:
+    FREELIST mFreeList;
+};
+
+#define UTILS_MAX(a,b) ((a) > (b) ? (a) : (b))
+
+template <typename T, size_t OFFSET = 0>
+using ObjectPoolAllocator = PoolAllocator<sizeof(T),
+        UTILS_MAX(alignof(FreeList), alignof(T)), OFFSET>;
+
+template <typename T, size_t OFFSET = 0>
+using ThreadSafeObjectPoolAllocator = PoolAllocator<sizeof(T),
+        UTILS_MAX(alignof(FreeList), alignof(T)), OFFSET, AtomicFreeList>;
+
+
+// ------------------------------------------------------------------------------------------------
+// Areas
+// ------------------------------------------------------------------------------------------------
+
+namespace AreaPolicy {
+
+class StaticArea {
+public:
+    StaticArea() noexcept = default;
+
+    StaticArea(void* b, void* e) noexcept
+            : mBegin(b), mEnd(e) {
+    }
+
+    ~StaticArea() noexcept = default;
+
+    StaticArea(const StaticArea& rhs) = default;
+    StaticArea& operator=(const StaticArea& rhs) = default;
+    StaticArea(StaticArea&& rhs) noexcept = default;
+    StaticArea& operator=(StaticArea&& rhs) noexcept = default;
+
+    void* data() const noexcept { return mBegin; }
+    void* begin() const noexcept { return mBegin; }
+    void* end() const noexcept { return mEnd; }
+    size_t size() const noexcept { return uintptr_t(mEnd) - uintptr_t(mBegin); }
+
+    friend void swap(StaticArea& lhs, StaticArea& rhs) noexcept {
+        using std::swap;
+        swap(lhs.mBegin, rhs.mBegin);
+        swap(lhs.mEnd, rhs.mEnd);
+    }
+
+private:
+    void* mBegin = nullptr;
+    void* mEnd = nullptr;
+};
+
+class HeapArea {
+public:
+    HeapArea() noexcept = default;
+
+    explicit HeapArea(size_t size) {
+        if (size) {
+            // TODO: policy committing memory
+            mBegin = malloc(size);
+            mEnd = pointermath::add(mBegin, size);
+        }
+    }
+
+    ~HeapArea() noexcept {
+        // TODO: policy for returning memory to system
+        free(mBegin);
+    }
+
+    HeapArea(const HeapArea& rhs) = delete;
+    HeapArea& operator=(const HeapArea& rhs) = delete;
+    HeapArea(HeapArea&& rhs) noexcept = delete;
+    HeapArea& operator=(HeapArea&& rhs) noexcept = delete;
+
+    void* data() const noexcept { return mBegin; }
+    void* begin() const noexcept { return mBegin; }
+    void* end() const noexcept { return mEnd; }
+    size_t size() const noexcept { return uintptr_t(mEnd) - uintptr_t(mBegin); }
+
+    friend void swap(HeapArea& lhs, HeapArea& rhs) noexcept {
+        using std::swap;
+        swap(lhs.mBegin, rhs.mBegin);
+        swap(lhs.mEnd, rhs.mEnd);
+    }
+
+private:
+    void* mBegin = nullptr;
+    void* mEnd = nullptr;
+};
+
+class NullArea {
+public:
+    void* data() const noexcept { return nullptr; }
+    size_t size() const noexcept { return 0; }
+};
+
+} // namespace AreaPolicy
+
+// ------------------------------------------------------------------------------------------------
+// Policies
+// ------------------------------------------------------------------------------------------------
+
+namespace LockingPolicy {
+
+struct NoLock {
+    void lock() noexcept { }
+    void unlock() noexcept { }
+};
+
+using SpinLock = utils::SpinLock;
+using Mutex = utils::Mutex;
+
+} // namespace LockingPolicy
+
+
+namespace TrackingPolicy {
+
+// default no-op tracker
+struct Untracked {
+    Untracked() noexcept = default;
+    Untracked(const char* name, void* base, size_t size) noexcept {
+        (void)name, void(base), (void)size;
+    }
+    void onAlloc(void* p, size_t size, size_t alignment, size_t extra) noexcept {
+        (void)p, (void)size, (void)alignment, (void)extra;
+    }
+    void onFree(void* p, size_t = 0) noexcept { (void)p; }
+    void onReset() noexcept { }
+    void onRewind(void* addr) noexcept { (void)addr; }
+};
+
+// This just track the max memory usage and logs it in the destructor
+struct HighWatermark {
+    HighWatermark() noexcept = default;
+    HighWatermark(const char* name, void* base, size_t size) noexcept
+        : mName(name), mBase(base), mSize(uint32_t(size)) { }
+    ~HighWatermark() noexcept;
+    void onAlloc(void* p, size_t size, size_t alignment, size_t extra) noexcept;
+    void onFree(void* p, size_t size) noexcept;
+    void onReset() noexcept;
+    void onRewind(void const* addr) noexcept;
+    uint32_t getHighWatermark() const noexcept { return mHighWaterMark; }
+protected:
+    const char* mName = nullptr;
+    void* mBase = nullptr;
+    uint32_t mSize = 0;
+    uint32_t mCurrent = 0;
+    uint32_t mHighWaterMark = 0;
+};
+
+// This just fills buffers with known values to help catch uninitialized access and use after free.
+struct Debug {
+    Debug() noexcept = default;
+    Debug(const char* name, void* base, size_t size) noexcept
+            : mName(name), mBase(base), mSize(uint32_t(size)) { }
+    void onAlloc(void* p, size_t size, size_t alignment, size_t extra) noexcept;
+    void onFree(void* p, size_t size) noexcept;
+    void onReset() noexcept;
+    void onRewind(void* addr) noexcept;
+protected:
+    const char* mName = nullptr;
+    void* mBase = nullptr;
+    uint32_t mSize = 0;
+};
+
+struct DebugAndHighWatermark : protected HighWatermark, protected Debug {
+    DebugAndHighWatermark() noexcept = default;
+    DebugAndHighWatermark(const char* name, void* base, size_t size) noexcept
+            : HighWatermark(name, base, size), Debug(name, base, size) { }
+    void onAlloc(void* p, size_t size, size_t alignment, size_t extra) noexcept {
+        HighWatermark::onAlloc(p, size, alignment, extra);
+        Debug::onAlloc(p, size, alignment, extra);
+    }
+    void onFree(void* p, size_t size) noexcept {
+        HighWatermark::onFree(p, size);
+        Debug::onFree(p, size);
+    }
+    void onReset() noexcept {
+        HighWatermark::onReset();
+        Debug::onReset();
+    }
+    void onRewind(void* addr) noexcept {
+        HighWatermark::onRewind(addr);
+        Debug::onRewind(addr);
+    }
+};
+
+} // namespace TrackingPolicy
+
+// ------------------------------------------------------------------------------------------------
+// Arenas
+// ------------------------------------------------------------------------------------------------
+
+template<typename AllocatorPolicy, typename LockingPolicy,
+        typename TrackingPolicy = TrackingPolicy::Untracked,
+        typename AreaPolicy = AreaPolicy::HeapArea>
+class Arena {
+public:
+
+    Arena() = default;
+
+    // construct an arena with a name and forward argument to its allocator
+    template<typename ... ARGS>
+    Arena(const char* name, size_t size, ARGS&& ... args)
+            : mArenaName(name),
+              mArea(size),
+              mAllocator(mArea, std::forward<ARGS>(args) ... ),
+              mListener(name, mArea.data(), mArea.size()) {
+    }
+
+    template<typename ... ARGS>
+    Arena(const char* name, AreaPolicy&& area, ARGS&& ... args)
+            : mArenaName(name),
+              mArea(std::forward<AreaPolicy>(area)),
+              mAllocator(mArea, std::forward<ARGS>(args) ... ),
+              mListener(name, mArea.data(), mArea.size()) {
+    }
+
+    // allocate memory from arena with given size and alignment
+    // (acceptable size/alignment may depend on the allocator provided)
+    void* alloc(size_t size, size_t alignment = alignof(std::max_align_t), size_t extra = 0) noexcept {
+        std::lock_guard<LockingPolicy> guard(mLock);
+        void* p = mAllocator.alloc(size, alignment, extra);
+        mListener.onAlloc(p, size, alignment, extra);
+        return p;
+    }
+
+    // Allocate an array of trivially destructible objects
+    // for safety, we disable the object-based alloc method if the object type is not
+    // trivially destructible, since free() won't call the destructor and this is allocating
+    // an array.
+    template <typename T,
+            typename = typename std::enable_if<std::is_trivially_destructible<T>::value>::type>
+    T* alloc(size_t count, size_t alignment = alignof(T), size_t extra = 0) noexcept {
+        return (T*)alloc(count * sizeof(T), alignment, extra);
+    }
+
+    // return memory pointed by p to the arena
+    // (actual behaviour may depend on allocator provided)
+    void free(void* p) noexcept {
+        if (p) {
+            std::lock_guard<LockingPolicy> guard(mLock);
+            mListener.onFree(p);
+            mAllocator.free(p);
+        }
+    }
+
+    // some allocators require the size of the allocation for free
+    void free(void* p, size_t size) noexcept {
+        if (p) {
+            std::lock_guard<LockingPolicy> guard(mLock);
+            mListener.onFree(p, size);
+            mAllocator.free(p, size);
+        }
+    }
+
+    // some allocators don't have a free() call, but a single reset() or rewind() instead
+    void reset() noexcept {
+        std::lock_guard<LockingPolicy> guard(mLock);
+        mListener.onReset();
+        mAllocator.reset();
+    }
+
+    void* getCurrent() noexcept { return mAllocator.getCurrent(); }
+
+    void rewind(void *addr) noexcept {
+        std::lock_guard<LockingPolicy> guard(mLock);
+        mListener.onRewind(addr);
+        mAllocator.rewind(addr);
+    }
+
+    // Allocate and construct an object
+    template<typename T, size_t ALIGN = alignof(T), typename... ARGS>
+    T* make(ARGS&& ... args) noexcept {
+        void* const p = this->alloc(sizeof(T), ALIGN);
+        return p ? new(p) T(std::forward<ARGS>(args)...) : nullptr;
+    }
+
+    // destroys an object created with make<T>() above, and frees associated memory
+    template<typename T>
+    void destroy(T* p) noexcept {
+        if (p) {
+            p->~T();
+            this->free((void*)p, sizeof(T));
+        }
+    }
+
+    char const* getName() const noexcept { return mArenaName; }
+
+    AllocatorPolicy& getAllocator() noexcept { return mAllocator; }
+    AllocatorPolicy const& getAllocator() const noexcept { return mAllocator; }
+
+    TrackingPolicy& getListener() noexcept { return mListener; }
+    TrackingPolicy const& getListener() const noexcept { return mListener; }
+
+    AreaPolicy& getArea() noexcept { return mArea; }
+    AreaPolicy const& getArea() const noexcept { return mArea; }
+
+    void setListener(TrackingPolicy listener) noexcept {
+        std::swap(mListener, listener);
+    }
+
+    template <typename ... ARGS>
+    void emplaceListener(ARGS&& ... args) noexcept {
+        mListener.~TrackingPolicy();
+        new (&mListener) TrackingPolicy(std::forward<ARGS>(args)...);
+    }
+
+    // An arena can't be copied
+    Arena(Arena const& rhs) noexcept = delete;
+    Arena& operator=(Arena const& rhs) noexcept = delete;
+
+    friend void swap(Arena& lhs, Arena& rhs) noexcept {
+        using std::swap;
+        swap(lhs.mArea, rhs.mArea);
+        swap(lhs.mAllocator, rhs.mAllocator);
+        swap(lhs.mLock, rhs.mLock);
+        swap(lhs.mListener, rhs.mListener);
+        swap(lhs.mArenaName, rhs.mArenaName);
+    }
+
+private:
+    char const* mArenaName = nullptr;
+    AreaPolicy mArea;
+    // note: we should use something like compressed_pair for the members below
+    AllocatorPolicy mAllocator;
+    LockingPolicy mLock;
+    TrackingPolicy mListener;
+};
+
+// ------------------------------------------------------------------------------------------------
+
+template<typename TrackingPolicy = TrackingPolicy::Untracked>
+using HeapArena = Arena<HeapAllocator, LockingPolicy::NoLock, TrackingPolicy>;
+
+// ------------------------------------------------------------------------------------------------
+
+// This doesn't implement our allocator concept, because it's too risky to use this as an allocator
+// in particular, doing ArenaScope<ArenaScope>.
+template<typename ARENA>
+class ArenaScope {
+
+    struct Finalizer {
+        void (*finalizer)(void* p) = nullptr;
+        Finalizer* next = nullptr;
+    };
+
+    template <typename T>
+    static void destruct(void* p) noexcept {
+        static_cast<T*>(p)->~T();
+    }
+
+public:
+    explicit ArenaScope(ARENA& allocator)
+            : mArena(allocator), mRewind(allocator.getCurrent()) {
+    }
+
+    ArenaScope& operator=(const ArenaScope& rhs) = delete;
+    ArenaScope(ArenaScope&& rhs) noexcept = delete;
+    ArenaScope& operator=(ArenaScope&& rhs) noexcept = delete;
+
+    ~ArenaScope() {
+        // run the finalizer chain
+        Finalizer* head = mFinalizerHead;
+        while (head) {
+            void* p = pointermath::add(head, sizeof(Finalizer));
+            head->finalizer(p);
+            head = head->next;
+        }
+        // ArenaScope works only with Arena that implements rewind()
+        mArena.rewind(mRewind);
+    }
+
+    template<typename T, size_t ALIGN = alignof(T), typename... ARGS>
+    T* make(ARGS&& ... args) noexcept {
+        T* o = nullptr;
+        if (std::is_trivially_destructible<T>::value) {
+            o = mArena.template make<T, ALIGN>(std::forward<ARGS>(args)...);
+        } else {
+            void* const p = (Finalizer*)mArena.alloc(sizeof(T), ALIGN, sizeof(Finalizer));
+            if (p != nullptr) {
+                Finalizer* const f = static_cast<Finalizer*>(p) - 1;
+                // constructor must be called before adding the dtor to the list
+                // so that the ctor can allocate objects in a nested scope and have the
+                // finalizers called in reverse order.
+                o = new(p) T(std::forward<ARGS>(args)...);
+                f->finalizer = &destruct<T>;
+                f->next = mFinalizerHead;
+                mFinalizerHead = f;
+            }
+        }
+        return o;
+    }
+
+    void* allocate(size_t size, size_t alignment = 1) noexcept {
+        return mArena.template alloc<uint8_t>(size, alignment, 0);
+    }
+
+    template <typename T>
+    T* allocate(size_t size, size_t alignment = alignof(T), size_t extra = 0) noexcept {
+        return mArena.template alloc<T>(size, alignment, extra);
+    }
+
+    // use with caution
+    ARENA& getAllocator() noexcept { return mArena; }
+
+private:
+    ARENA& mArena;
+    void* mRewind = nullptr;
+    Finalizer* mFinalizerHead = nullptr;
+};
+
+
+template <typename TYPE, typename ARENA>
+class STLAllocator {
+public:
+    using value_type = TYPE;
+    using pointer = TYPE*;
+    using const_pointer = const TYPE*;
+    using reference = TYPE&;
+    using const_reference = const TYPE&;
+    using size_type = std::size_t;
+    using difference_type = std::ptrdiff_t;
+    using propagate_on_container_move_assignment = std::true_type;
+    using is_always_equal = std::true_type;
+
+    template<typename OTHER>
+    struct rebind { using other = STLAllocator<OTHER, ARENA>; };
+
+public:
+    // we don't make this explicit, so that we can initialize a vector using a STLAllocator
+    // from an Arena, avoiding to have to repeat the vector type.
+    STLAllocator(ARENA& arena) : mArena(arena) { } // NOLINT(google-explicit-constructor)
+
+    template<typename U>
+    explicit STLAllocator(STLAllocator<U, ARENA> const& rhs) : mArena(rhs.mArena) { }
+
+    TYPE* allocate(std::size_t n) {
+        auto p = static_cast<TYPE *>(mArena.alloc(n * sizeof(TYPE), alignof(TYPE)));
+        assert_invariant(p);
+        return p;
+    }
+
+    void deallocate(TYPE* p, std::size_t n) {
+        mArena.free(p, n * sizeof(TYPE));
+    }
+
+    // these should be out-of-class friends, but this doesn't seem to work with some compilers
+    // which complain about multiple definition each time a STLAllocator<> is instantiated.
+    template <typename U, typename A>
+    bool operator==(const STLAllocator<U, A>& rhs) const noexcept {
+        return std::addressof(mArena) == std::addressof(rhs.mArena);
+    }
+
+    template <typename U, typename A>
+    bool operator!=(const STLAllocator<U, A>& rhs) const noexcept {
+        return !operator==(rhs);
+    }
+
+private:
+    template<typename U, typename A>
+    friend class STLAllocator;
+
+    ARENA& mArena;
+};
+
+} // namespace utils
+
+#endif // TNT_UTILS_ALLOCATOR_H

flutter_filament/windows/include/filament/utils/BitmaskEnum.h

@@ -0,0 +1,145 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_BITMASKENUM_H
+#define TNT_UTILS_BITMASKENUM_H
+
+#include <utils/compiler.h>
+
+#include <type_traits> // for std::false_type
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
+
+namespace utils {
+
+template<typename Enum>
+struct EnableBitMaskOperators : public std::false_type { };
+
+template<typename Enum>
+struct EnableIntegerOperators : public std::false_type { };
+
+namespace Enum {
+
+template<typename Enum>
+size_t count();
+
+} // namespace enum
+} // namespace utils
+
+// ------------------------------------------------------------------------------------------------
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableIntegerOperators<Enum>::value, int> = 0>
+inline constexpr int operator+(Enum value) noexcept {
+    return int(value);
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableIntegerOperators<Enum>::value, int> = 0>
+inline constexpr bool operator==(Enum lhs, size_t rhs) noexcept {
+    using underlying_t = std::underlying_type_t<Enum>;
+    return underlying_t(lhs) == rhs;
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableIntegerOperators<Enum>::value, int> = 0>
+inline constexpr bool operator==(size_t lhs, Enum rhs) noexcept {
+    return rhs == lhs;
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableIntegerOperators<Enum>::value, int> = 0>
+inline constexpr bool operator!=(Enum lhs, size_t rhs) noexcept {
+    return !(rhs == lhs);
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableIntegerOperators<Enum>::value, int> = 0>
+inline constexpr bool operator!=(size_t lhs, Enum rhs) noexcept {
+    return rhs != lhs;
+}
+
+// ------------------------------------------------------------------------------------------------
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableBitMaskOperators<Enum>::value, int> = 0>
+inline constexpr bool operator!(Enum rhs) noexcept {
+    using underlying = std::underlying_type_t<Enum>;
+    return underlying(rhs) == 0;
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableBitMaskOperators<Enum>::value, int> = 0>
+inline constexpr Enum operator~(Enum rhs) noexcept {
+    using underlying = std::underlying_type_t<Enum>;
+    return Enum(~underlying(rhs));
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableBitMaskOperators<Enum>::value, int> = 0>
+inline constexpr Enum operator|(Enum lhs, Enum rhs) noexcept {
+    using underlying = std::underlying_type_t<Enum>;
+    return Enum(underlying(lhs) | underlying(rhs));
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableBitMaskOperators<Enum>::value, int> = 0>
+inline constexpr Enum operator&(Enum lhs, Enum rhs) noexcept {
+    using underlying = std::underlying_type_t<Enum>;
+    return Enum(underlying(lhs) & underlying(rhs));
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableBitMaskOperators<Enum>::value, int> = 0>
+inline constexpr Enum operator^(Enum lhs, Enum rhs) noexcept {
+    using underlying = std::underlying_type_t<Enum>;
+    return Enum(underlying(lhs) ^ underlying(rhs));
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableBitMaskOperators<Enum>::value, int> = 0>
+inline constexpr Enum operator|=(Enum& lhs, Enum rhs) noexcept {
+    return lhs = lhs | rhs;
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableBitMaskOperators<Enum>::value, int> = 0>
+inline constexpr Enum operator&=(Enum& lhs, Enum rhs) noexcept {
+    return lhs = lhs & rhs;
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableBitMaskOperators<Enum>::value, int> = 0>
+inline constexpr Enum operator^=(Enum& lhs, Enum rhs) noexcept {
+    return lhs = lhs ^ rhs;
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableBitMaskOperators<Enum>::value, int> = 0>
+inline constexpr bool none(Enum lhs) noexcept {
+    return !lhs;
+}
+
+template<typename Enum, typename std::enable_if_t<
+        std::is_enum<Enum>::value && utils::EnableBitMaskOperators<Enum>::value, int> = 0>
+inline constexpr bool any(Enum lhs) noexcept {
+    return !none(lhs);
+}
+
+
+#endif // TNT_UTILS_BITMASKENUM_H

flutter_filament/windows/include/filament/utils/CString.h

@@ -0,0 +1,230 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_CSTRING_H
+#define TNT_UTILS_CSTRING_H
+
+// NOTE: this header should not include STL headers
+
+#include <utils/compiler.h>
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+namespace utils {
+
+//! \privatesection
+struct hashCStrings {
+    typedef const char* argument_type;
+    typedef size_t result_type;
+    result_type operator()(argument_type cstr) const noexcept {
+        size_t hash = 5381;
+        while (int c = *cstr++) {
+            hash = (hash * 33u) ^ size_t(c);
+        }
+        return hash;
+    }
+};
+
+template <size_t N>
+using StringLiteral = const char[N];
+
+
+// ------------------------------------------------------------------------------------------------
+
+class UTILS_PUBLIC CString {
+public:
+    using value_type      = char;
+    using size_type       = uint32_t;
+    using difference_type = int32_t;
+    using reference       = value_type&;
+    using const_reference = const value_type&;
+    using pointer         = value_type*;
+    using const_pointer   = const value_type*;
+    using iterator        = value_type*;
+    using const_iterator  = const value_type*;
+
+    CString() noexcept {} // NOLINT(modernize-use-equals-default), Ubuntu compiler bug
+
+    // Allocates memory and appends a null. This constructor can be used to hold arbitrary data
+    // inside the string (i.e. it can contain nulls or non-ASCII encodings).
+    CString(const char* cstr, size_t length);
+
+    // Allocates memory for a string of size length plus space for the null terminating character.
+    // Also initializes the memory to 0. This constructor can be used to hold arbitrary data
+    // inside the string.
+    explicit CString(size_t length);
+
+    // Allocates memory and copies traditional C string content. Unlike the above constructor, this
+    // does not allow embedded nulls. This is explicit because this operation is costly.
+    explicit CString(const char* cstr);
+
+    template<size_t N>
+    CString(StringLiteral<N> const& other) noexcept // NOLINT(google-explicit-constructor)
+            : CString(other, N - 1) {
+    }
+
+    CString(const CString& rhs);
+
+    CString(CString&& rhs) noexcept {
+        this->swap(rhs);
+    }
+
+
+    CString& operator=(const CString& rhs);
+
+    CString& operator=(CString&& rhs) noexcept {
+        this->swap(rhs);
+        return *this;
+    }
+
+    ~CString() noexcept {
+        if (mData) {
+            free(mData - 1);
+        }
+    }
+
+    void swap(CString& other) noexcept {
+        // don't use std::swap(), we don't want an STL dependency in this file
+        auto *temp = mCStr;
+        mCStr = other.mCStr;
+        other.mCStr = temp;
+    }
+
+    const_pointer c_str() const noexcept { return mCStr; }
+    pointer c_str() noexcept { return mCStr; }
+    const_pointer c_str_safe() const noexcept { return mData ? c_str() : ""; }
+    const_pointer data() const noexcept { return c_str(); }
+    pointer data() noexcept { return c_str(); }
+    size_type size() const noexcept { return mData ? mData[-1].length : 0; }
+    size_type length() const noexcept { return size(); }
+    bool empty() const noexcept { return size() == 0; }
+
+    iterator begin() noexcept { return mCStr; }
+    iterator end() noexcept { return begin() + length(); }
+    const_iterator begin() const noexcept { return data(); }
+    const_iterator end() const noexcept { return begin() + length(); }
+    const_iterator cbegin() const noexcept { return begin(); }
+    const_iterator cend() const noexcept { return end(); }
+
+    CString& replace(size_type pos, size_type len, const CString& str) noexcept;
+    CString& insert(size_type pos, const CString& str) noexcept { return replace(pos, 0, str); }
+
+    const_reference operator[](size_type pos) const noexcept {
+        assert(pos < size());
+        return begin()[pos];
+    }
+
+    reference operator[](size_type pos) noexcept {
+        assert(pos < size());
+        return begin()[pos];
+    }
+
+    const_reference at(size_type pos) const noexcept {
+        assert(pos < size());
+        return begin()[pos];
+    }
+
+    reference at(size_type pos) noexcept {
+        assert(pos < size());
+        return begin()[pos];
+    }
+
+    reference front() noexcept {
+        assert(size());
+        return begin()[0];
+    }
+
+    const_reference front() const noexcept {
+        assert(size());
+        return begin()[0];
+    }
+
+    reference back() noexcept {
+        assert(size());
+        return begin()[size() - 1];
+    }
+
+    const_reference back() const noexcept {
+        assert(size());
+        return begin()[size() - 1];
+    }
+
+    // placement new declared as "throw" to avoid the compiler's null-check
+    inline void* operator new(size_t, void* ptr) {
+        assert(ptr);
+        return ptr;
+    }
+
+    struct Hasher : private hashCStrings {
+        typedef CString argument_type;
+        typedef size_t result_type;
+        result_type operator()(const argument_type& s) const noexcept {
+            return hashCStrings::operator()(s.c_str());
+        }
+    };
+
+private:
+    struct Data {
+        size_type length;
+    };
+
+    // mCStr points to the C-string or nullptr. if non-null, mCStr is preceded by the string's size
+    union {
+        value_type *mCStr = nullptr;
+        Data* mData; // Data is stored at mData[-1]
+    };
+
+    int compare(const CString& rhs) const noexcept {
+        size_type lhs_size = size();
+        size_type rhs_size = rhs.size();
+        if (lhs_size < rhs_size) return -1;
+        if (lhs_size > rhs_size) return 1;
+        return strncmp(data(), rhs.data(), size());
+    }
+
+    friend bool operator==(CString const& lhs, CString const& rhs) noexcept {
+        return (lhs.data() == rhs.data()) ||
+               ((lhs.size() == rhs.size()) && !strncmp(lhs.data(), rhs.data(), lhs.size()));
+    }
+    friend bool operator!=(CString const& lhs, CString const& rhs) noexcept {
+        return !(lhs == rhs);
+    }
+    friend bool operator<(CString const& lhs, CString const& rhs) noexcept {
+        return lhs.compare(rhs) < 0;
+    }
+    friend bool operator>(CString const& lhs, CString const& rhs) noexcept {
+        return lhs.compare(rhs) > 0;
+    }
+    friend bool operator>=(CString const& lhs, CString const& rhs) noexcept {
+        return !(lhs < rhs);
+    }
+    friend bool operator<=(CString const& lhs, CString const& rhs) noexcept {
+        return !(lhs > rhs);
+    }
+};
+
+// implement this for your type for automatic conversion to CString. Failing to do so leads
+// to a compile-time failure.
+template<typename T>
+CString to_string(T value) noexcept;
+
+} // namespace utils
+
+#endif // TNT_UTILS_CSTRING_H

flutter_filament/windows/include/filament/utils/CallStack.h

@@ -0,0 +1,127 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef UTILS_CALLSTACK_H
+#define UTILS_CALLSTACK_H
+
+#include <stddef.h>
+#include <stdint.h>
+#include <typeinfo>
+
+#include <utils/CString.h>
+#include <utils/Log.h>
+
+namespace utils {
+
+/**
+ * CallStack captures the current's thread call stack.
+ */
+class CallStack {
+public:
+    /**
+     * Creates an empty call stack
+     * @see CallStack::capture()
+     */
+    CallStack() = default;
+    CallStack(const CallStack&) = default;
+    ~CallStack() = default;
+
+    /**
+     * A convenience method to create and capture the stack trace in one go.
+     * @param ignore number frames to ignore at the top of the stack.
+     * @return A CallStack object
+     */
+    static CallStack unwind(size_t ignore = 0) noexcept;
+
+    /**
+     * Capture the current thread's stack and replaces the existing one if any.
+     * @param ignore number frames to ignore at the top of the stack.
+     */
+    void update(size_t ignore = 0) noexcept;
+
+    /**
+     * Get the number of stack frames this object has recorded.
+     * @return How many stack frames are accessible through operator[]
+     */
+    size_t getFrameCount() const noexcept;
+
+    /**
+     * Return the program-counter of each stack frame captured
+     * @param index of the frame between 0 and getFrameCount()-1
+     * @return the program-counter of the stack-frame recorded at index \p index
+     * @throw std::out_of_range if the index is out of range
+     */
+    intptr_t operator [](size_t index) const;
+
+   /** Demangles a C++ type name */
+    static utils::CString demangleTypeName(const char* mangled);
+
+    template<typename T>
+    static utils::CString typeName() {
+#if UTILS_HAS_RTTI
+        return demangleTypeName(typeid(T).name());
+#else
+        return CString("<no-rtti>");
+#endif
+    }
+
+    /**
+     * Outputs a CallStack into a stream.
+     * This will print, when possible, the demangled names of functions corresponding to the
+     * program-counter recorded.
+     */
+    friend utils::io::ostream& operator <<(utils::io::ostream& stream, const CallStack& callstack);
+
+    bool operator <(const CallStack& rhs) const;
+
+    inline bool operator >(const CallStack& rhs) const {
+        return rhs < *this;
+    }
+
+    inline bool operator !=(const CallStack& rhs) const {
+        return *this < rhs || rhs < *this;
+    }
+
+    inline bool operator >=(const CallStack& rhs) const {
+        return !operator <(rhs);
+    }
+
+    inline bool operator <=(const CallStack& rhs) const {
+        return !operator >(rhs);
+    }
+
+    inline bool operator ==(const CallStack& rhs) const {
+        return !operator !=(rhs);
+    }
+
+private:
+    void update_gcc(size_t ignore) noexcept;
+
+    static utils::CString demangle(const char* mangled);
+
+    static constexpr size_t NUM_FRAMES = 20;
+
+    struct StackFrameInfo {
+        intptr_t pc;
+    };
+
+    size_t m_frame_count = 0;
+    StackFrameInfo m_stack[NUM_FRAMES];
+};
+
+} // namespace utils
+
+#endif // UTILS_CALLSTACK_H

flutter_filament/windows/include/filament/utils/Entity.h

@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_ENTITY_H
+#define TNT_UTILS_ENTITY_H
+
+#include <utils/compiler.h>
+
+#include <stdint.h>
+#include <stddef.h>
+
+namespace utils {
+
+class UTILS_PUBLIC Entity {
+public:
+    // this can be used to create an array of to-be-filled entities (see create())
+    Entity() noexcept { } // NOLINT(modernize-use-equals-default), Ubuntu compiler bug
+
+    // Entities can be copied
+    Entity(const Entity& e) noexcept = default;
+    Entity(Entity&& e) noexcept = default;
+    Entity& operator=(const Entity& e) noexcept = default;
+    Entity& operator=(Entity&& e) noexcept = default;
+
+    // Entities can be compared
+    bool operator==(Entity e) const { return e.mIdentity == mIdentity; }
+    bool operator!=(Entity e) const { return e.mIdentity != mIdentity; }
+
+    // Entities can be sorted
+    bool operator<(Entity e) const { return e.mIdentity < mIdentity; }
+
+    bool isNull() const noexcept {
+        return mIdentity == 0;
+    }
+
+    // an id that can be used for debugging/printing
+    uint32_t getId() const noexcept {
+        return mIdentity;
+    }
+
+    explicit operator bool() const noexcept { return !isNull(); }
+
+    void clear() noexcept  { mIdentity = 0; }
+
+    // Exports an entity to an int32_t which can be used "as is" in the Java programing language.
+    static int32_t smuggle(Entity entity) noexcept {
+        return int32_t(entity.getId());
+    }
+
+    // Imports an entity from an int32_t generated by smuggle() above.
+    static Entity import(int32_t identity) noexcept {
+        return Entity{ Type(identity) };
+    }
+
+    struct Hasher {
+        typedef Entity argument_type;
+        typedef size_t result_type;
+        result_type operator()(argument_type const& e) const {
+            return e.getId();
+        }
+    };
+
+private:
+    friend class EntityManager;
+    friend class EntityManagerImpl;
+    using Type = uint32_t;
+
+    explicit Entity(Type identity) noexcept : mIdentity(identity) { }
+
+    Type mIdentity = 0;
+};
+
+} // namespace utils
+
+#endif // TNT_UTILS_ENTITY_H

flutter_filament/windows/include/filament/utils/EntityInstance.h

@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_ENTITYINSTANCE_H
+#define TNT_UTILS_ENTITYINSTANCE_H
+
+#include <utils/compiler.h>
+
+#include <type_traits>
+
+#include <stdint.h>
+
+
+namespace utils {
+
+class UTILS_PUBLIC EntityInstanceBase {
+public:
+    using Type = uint32_t;
+protected:
+    Type mInstance = 0;
+};
+
+template <typename T, bool EDIT = false>
+class UTILS_PUBLIC EntityInstance : public EntityInstanceBase {
+public:
+    // default Instance is invalid
+    constexpr EntityInstance() noexcept = default;
+
+    // check if this Instance is valid
+    constexpr bool isValid() const noexcept { return mInstance != 0; }
+
+    // Instances of same type can be copied/assigned
+    constexpr EntityInstance(EntityInstance const& other) noexcept = default;
+    constexpr EntityInstance& operator=(EntityInstance const& other) noexcept = default;
+
+    // EDIT instances can be converted to "read" Instances of same type
+    template <typename = std::enable_if<!EDIT>>
+    constexpr explicit EntityInstance(EntityInstance<T, true> const& other) noexcept {
+        mInstance = other.asValue();
+    }
+    template <typename = std::enable_if<!EDIT>>
+    EntityInstance& operator=(EntityInstance<T, true> const& other) noexcept {
+        mInstance = other.asValue();
+        return *this;
+    }
+
+    // Instances can be compared
+    constexpr bool operator!=(EntityInstance e) const { return mInstance != e.mInstance; }
+    constexpr bool operator==(EntityInstance e) const { return mInstance == e.mInstance; }
+
+    // Instances can be sorted
+    constexpr bool operator<(EntityInstance e) const { return mInstance < e.mInstance; }
+    constexpr bool operator<=(EntityInstance e) const { return mInstance <= e.mInstance; }
+    constexpr bool operator>(EntityInstance e) const { return mInstance > e.mInstance; }
+    constexpr bool operator>=(EntityInstance e) const { return mInstance >= e.mInstance; }
+
+    // and we can iterate
+    constexpr EntityInstance& operator++() noexcept { ++mInstance; return *this; }
+    constexpr EntityInstance& operator--() noexcept { --mInstance; return *this; }
+    constexpr const EntityInstance operator++(int) const noexcept { return EntityInstance{ mInstance + 1 }; }
+    constexpr const EntityInstance operator--(int) const noexcept { return EntityInstance{ mInstance - 1 }; }
+
+
+    // return a value for this Instance (mostly needed for debugging
+    constexpr uint32_t asValue() const noexcept { return mInstance; }
+
+    // auto convert to Type so it can be used as an index
+    constexpr operator Type() const noexcept { return mInstance; } // NOLINT(google-explicit-constructor)
+
+    // conversion from Type so we can initialize from an index
+    constexpr EntityInstance(Type value) noexcept { mInstance = value; } // NOLINT(google-explicit-constructor)
+};
+
+} // namespace utils
+
+#endif // TNT_UTILS_ENTITYINSTANCE_H

flutter_filament/windows/include/filament/utils/EntityManager.h

@@ -0,0 +1,133 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_ENTITYMANAGER_H
+#define TNT_UTILS_ENTITYMANAGER_H
+
+#include <assert.h>
+#include <stdint.h>
+
+#include <utils/Entity.h>
+#include <utils/compiler.h>
+
+#ifndef FILAMENT_UTILS_TRACK_ENTITIES
+#define FILAMENT_UTILS_TRACK_ENTITIES false
+#endif
+
+#if FILAMENT_UTILS_TRACK_ENTITIES
+#include <utils/ostream.h>
+#include <vector>
+#endif
+
+namespace utils {
+
+class UTILS_PUBLIC EntityManager {
+public:
+    // Get the global EntityManager. It is recommended to cache this value.
+    // Thread Safe.
+    static EntityManager& get() noexcept;
+
+    class Listener {
+    public:
+        virtual void onEntitiesDestroyed(size_t n, Entity const* entities) noexcept = 0;
+    protected:
+        ~Listener() noexcept;
+    };
+
+
+    // maximum number of entities that can exist at the same time
+    static size_t getMaxEntityCount() noexcept {
+        // because index 0 is reserved, we only have 2^GENERATION_SHIFT - 1 valid indices
+        return RAW_INDEX_COUNT - 1;
+    }
+
+    // create n entities. Thread safe.
+    void create(size_t n, Entity* entities);
+
+    // destroys n entities. Thread safe.
+    void destroy(size_t n, Entity* entities) noexcept;
+
+    // create a new Entity. Thread safe.
+    // Return Entity.isNull() if the entity cannot be allocated.
+    Entity create() {
+        Entity e;
+        create(1, &e);
+        return e;
+    }
+
+    // destroys an Entity. Thread safe.
+    void destroy(Entity e) noexcept {
+        destroy(1, &e);
+    }
+
+    // return whether the given Entity has been destroyed (false) or not (true).
+    // Thread safe.
+    bool isAlive(Entity e) const noexcept {
+        assert(getIndex(e) < RAW_INDEX_COUNT);
+        return (!e.isNull()) && (getGeneration(e) == mGens[getIndex(e)]);
+    }
+
+    // registers a listener to be called when an entity is destroyed. thread safe.
+    // if the listener is already register, this method has no effect.
+    void registerListener(Listener* l) noexcept;
+
+    // unregisters a listener.
+    void unregisterListener(Listener* l) noexcept;
+
+
+    /* no user serviceable parts below */
+
+    // current generation of the given index. Use for debugging and testing.
+    uint8_t getGenerationForIndex(size_t index) const noexcept {
+        return mGens[index];
+    }
+    // singleton, can't be copied
+    EntityManager(const EntityManager& rhs) = delete;
+    EntityManager& operator=(const EntityManager& rhs) = delete;
+
+#if FILAMENT_UTILS_TRACK_ENTITIES
+    std::vector<Entity> getActiveEntities() const;
+    void dumpActiveEntities(utils::io::ostream& out) const;
+#endif
+
+private:
+    friend class EntityManagerImpl;
+    EntityManager();
+    ~EntityManager();
+
+    // GENERATION_SHIFT determines how many simultaneous Entities are available, the
+    // minimum memory requirement is 2^GENERATION_SHIFT bytes.
+    static constexpr const int GENERATION_SHIFT = 17;
+    static constexpr const size_t RAW_INDEX_COUNT = (1 << GENERATION_SHIFT);
+    static constexpr const Entity::Type INDEX_MASK = (1 << GENERATION_SHIFT) - 1u;
+
+    static inline Entity::Type getGeneration(Entity e) noexcept {
+        return e.getId() >> GENERATION_SHIFT;
+    }
+    static inline Entity::Type getIndex(Entity e) noexcept  {
+        return e.getId() & INDEX_MASK;
+    }
+    static inline Entity::Type makeIdentity(Entity::Type g, Entity::Type i) noexcept {
+        return (g << GENERATION_SHIFT) | (i & INDEX_MASK);
+    }
+
+    // stores the generation of each index.
+    uint8_t * const mGens;
+};
+
+} // namespace utils
+
+#endif // TNT_UTILS_ENTITYMANAGER_H

flutter_filament/windows/include/filament/utils/FixedCapacityVector.h

@@ -0,0 +1,420 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_FIXEDCAPACITYVECTOR_H
+#define TNT_UTILS_FIXEDCAPACITYVECTOR_H
+
+#include <utils/compressed_pair.h>
+#include <utils/Panic.h>
+
+#include <initializer_list>
+#include <limits>
+#include <memory>
+#include <type_traits>
+#include <utility>
+#include <vector> // TODO: is this necessary?
+
+#include <stddef.h>
+#include <stdint.h>
+
+#ifndef NDEBUG
+#define FILAMENT_FORCE_CAPACITY_CHECK true
+#else
+#define FILAMENT_FORCE_CAPACITY_CHECK false
+#endif
+
+namespace utils {
+
+/**
+ * FixedCapacityVector is (almost) a drop-in replacement for std::vector<> except it has a
+ * fixed capacity decided at runtime. The vector storage is never reallocated unless reserve()
+ * is called. Operations that add elements to the vector can fail if there is not enough
+ * capacity.
+ *
+ * An empty vector with a given capacity is created with
+ *   FixedCapacityVector<T>::with_capacity( capacity );
+ *
+ * NOTE: When passing an initial size into the FixedCapacityVector constructor, default construction
+ * of the elements is skipped when their construction is trivial. This behavior is different from
+ * std::vector. e.g., std::vector<int>(4) constructs 4 zeros while FixedCapacityVector<int>(4)
+ * allocates 4 uninitialized values. Note that zero initialization is easily achieved by passing in
+ * the optional value argument, e.g. FixedCapacityVector<int>(4, 0) or foo.resize(4, 0).
+ */
+template<typename T, typename A = std::allocator<T>, bool CapacityCheck = true>
+class UTILS_PUBLIC FixedCapacityVector {
+public:
+    using allocator_type = A;
+    using value_type = T;
+    using reference = T&;
+    using const_reference = T const&;
+    using size_type = uint32_t;
+    using difference_type = int32_t;
+    using pointer = T*;
+    using const_pointer = T const*;
+    using iterator = pointer;
+    using const_iterator = const_pointer;
+    using reverse_iterator = std::reverse_iterator<iterator>;
+    using const_reverse_iterator = std::reverse_iterator<const_iterator>;
+
+private:
+    using storage_traits = std::allocator_traits<allocator_type>;
+
+public:
+    /** returns an empty vector with the specified capacity */
+    static FixedCapacityVector with_capacity(
+            size_type capacity, const allocator_type& allocator = allocator_type()) {
+        return FixedCapacityVector(construct_with_capacity, capacity, allocator);
+    }
+
+    FixedCapacityVector() = default;
+
+    explicit FixedCapacityVector(const allocator_type& allocator) noexcept
+            : mCapacityAllocator({}, allocator) {
+    }
+
+    explicit FixedCapacityVector(size_type size, const allocator_type& allocator = allocator_type())
+            : mSize(size),
+              mCapacityAllocator(size, allocator) {
+        mData = this->allocator().allocate(this->capacity());
+        construct(begin(), end());
+    }
+
+    FixedCapacityVector(std::initializer_list<T> list,
+            const allocator_type& alloc = allocator_type())
+            : mSize(list.size()),
+              mCapacityAllocator(list.size(), alloc) {
+        mData = this->allocator().allocate(this->capacity());
+        std::uninitialized_copy(list.begin(), list.end(), begin());
+    }
+
+    FixedCapacityVector(size_type size, const_reference value,
+            const allocator_type& alloc = allocator_type())
+            : mSize(size),
+              mCapacityAllocator(size, alloc) {
+        mData = this->allocator().allocate(this->capacity());
+        construct(begin(), end(), value);
+    }
+
+    FixedCapacityVector(FixedCapacityVector const& rhs)
+            : mSize(rhs.mSize),
+              mCapacityAllocator(rhs.capacity(),
+                    storage_traits::select_on_container_copy_construction(rhs.allocator())) {
+        mData = allocator().allocate(capacity());
+        std::uninitialized_copy(rhs.begin(), rhs.end(), begin());
+    }
+
+    FixedCapacityVector(FixedCapacityVector&& rhs) noexcept {
+        this->swap(rhs);
+    }
+
+    ~FixedCapacityVector() noexcept {
+        destroy(begin(), end());
+        allocator().deallocate(data(), capacity());
+    }
+
+    FixedCapacityVector& operator=(FixedCapacityVector const& rhs) {
+        if (this != &rhs) {
+            FixedCapacityVector t(rhs);
+            this->swap(t);
+        }
+        return *this;
+    }
+
+    FixedCapacityVector& operator=(FixedCapacityVector&& rhs) noexcept {
+        this->swap(rhs);
+        return *this;
+    }
+
+    allocator_type get_allocator() const noexcept {
+        return mCapacityAllocator.second();
+    }
+
+    // --------------------------------------------------------------------------------------------
+
+    iterator begin() noexcept { return data(); }
+    iterator end() noexcept { return data() + size(); }
+    const_iterator begin() const noexcept { return data(); }
+    const_iterator end() const noexcept { return data() + size(); }
+    reverse_iterator rbegin() noexcept { return reverse_iterator(end()); }
+    const_reverse_iterator rbegin() const noexcept { return const_reverse_iterator(end()); }
+    reverse_iterator rend() noexcept { return reverse_iterator(begin()); }
+    const_reverse_iterator rend() const noexcept { return const_reverse_iterator(begin()); }
+    const_iterator cbegin() const noexcept { return begin(); }
+    const_iterator cend() const noexcept { return end(); }
+    const_reverse_iterator crbegin() const noexcept { return rbegin(); }
+    const_reverse_iterator crend() const noexcept { return rend(); }
+
+    // --------------------------------------------------------------------------------------------
+
+    size_type size() const noexcept { return mSize; }
+    size_type capacity() const noexcept { return mCapacityAllocator.first(); }
+    bool empty() const noexcept { return size() == 0; }
+    size_type max_size() const noexcept {
+        return std::min(storage_traits::max_size(allocator()),
+                std::numeric_limits<size_type>::max());
+    }
+
+    // --------------------------------------------------------------------------------------------
+
+    reference operator[](size_type n) noexcept {
+        assert(n < size());
+        return *(begin() + n);
+    }
+
+    const_reference operator[](size_type n) const noexcept {
+        assert(n < size());
+        return *(begin() + n);
+    }
+
+    reference front() noexcept { return *begin(); }
+    const_reference front() const noexcept { return *begin(); }
+    reference back() noexcept { return *(end() - 1); }
+    const_reference back() const noexcept { return *(end() - 1); }
+    value_type* data() noexcept { return mData; }
+    const value_type* data() const noexcept { return mData; }
+
+    // --------------------------------------------------------------------------------------------
+
+    void push_back(const_reference v) {
+        auto pos = assertCapacityForSize(size() + 1);
+        ++mSize;
+        storage_traits::construct(allocator(), pos, v);
+    }
+
+    void push_back(value_type&& v) {
+        auto pos = assertCapacityForSize(size() + 1);
+        ++mSize;
+        storage_traits::construct(allocator(), pos, std::move(v));
+    }
+
+    template<typename ... ARGS>
+    reference emplace_back(ARGS&& ... args) {
+        auto pos = assertCapacityForSize(size() + 1);
+        ++mSize;
+        storage_traits::construct(allocator(), pos, std::forward<ARGS>(args)...);
+        return *pos;
+    }
+
+    void pop_back() {
+        assert(!empty());
+        --mSize;
+        destroy(end(), end() + 1);
+    }
+
+    iterator insert(const_iterator position, const_reference v) {
+        if (position == end()) {
+            push_back(v);
+        } else {
+            assertCapacityForSize(size() + 1);
+            pointer p = const_cast<pointer>(position);
+            move_range(p, end(), p + 1);
+            ++mSize;
+            // here we handle inserting an element of this vector!
+            const_pointer pv = std::addressof(v);
+            if (p <= pv && pv < end()) {
+                *p = *(pv + 1);
+            } else {
+                *p = v;
+            }
+        }
+        return const_cast<iterator>(position);
+    }
+
+    iterator insert(const_iterator position, value_type&& v) {
+        if (position == end()) {
+            push_back(std::move(v));
+        } else {
+            assertCapacityForSize(size() + 1);
+            pointer p = const_cast<pointer>(position);
+            move_range(p, end(), p + 1);
+            ++mSize;
+            *p = std::move(v);
+        }
+        return const_cast<iterator>(position);
+    }
+
+    iterator erase(const_iterator pos) {
+        assert(pos != end());
+        return erase(pos, pos + 1);
+    }
+
+    iterator erase(const_iterator first, const_iterator last) {
+        assert(first <= last);
+        auto e = std::move(const_cast<iterator>(last), end(), const_cast<iterator>(first));
+        destroy(e, end());
+        mSize -= std::distance(first, last);
+        return const_cast<iterator>(first);
+    }
+
+    void clear() noexcept {
+        destroy(begin(), end());
+        mSize = 0;
+    }
+
+    void resize(size_type count) {
+        assertCapacityForSize(count);
+        if constexpr(std::is_trivially_constructible_v<value_type> &&
+                     std::is_trivially_destructible_v<value_type>) {
+            // we check for triviality here so that the implementation could be non-inline
+            mSize = count;
+        } else {
+            resize_non_trivial(count);
+        }
+    }
+
+    void resize(size_type count, const_reference v) {
+        assertCapacityForSize(count);
+        resize_non_trivial(count, v);
+    }
+
+    void swap(FixedCapacityVector& other) {
+        using std::swap;
+        swap(mData, other.mData);
+        swap(mSize, other.mSize);
+        mCapacityAllocator.swap(other.mCapacityAllocator);
+    }
+
+    UTILS_NOINLINE
+    void reserve(size_type c) {
+        if (c > capacity()) {
+            FixedCapacityVector t(construct_with_capacity, c, allocator());
+            t.mSize = size();
+            std::uninitialized_move(begin(), end(), t.begin());
+            this->swap(t);
+        }
+    }
+
+private:
+    enum construct_with_capacity_tag{ construct_with_capacity };
+
+    FixedCapacityVector(construct_with_capacity_tag,
+            size_type capacity, const allocator_type& allocator = allocator_type())
+            : mCapacityAllocator(capacity, allocator) {
+        mData = this->allocator().allocate(this->capacity());
+    }
+
+    allocator_type& allocator() noexcept {
+        return mCapacityAllocator.second();
+    }
+
+    allocator_type const& allocator() const noexcept {
+        return mCapacityAllocator.second();
+    }
+
+    iterator assertCapacityForSize(size_type s) {
+        if constexpr(CapacityCheck || FILAMENT_FORCE_CAPACITY_CHECK) {
+            ASSERT_PRECONDITION(capacity() >= s,
+                    "capacity exceeded: requested size %lu, available capacity %lu.",
+                    (unsigned long)s, (unsigned long)capacity());
+        }
+        return end();
+    }
+
+    inline void construct(iterator first, iterator last) noexcept {
+        // we check for triviality here so that the implementation could be non-inline
+        if constexpr(!std::is_trivially_constructible_v<value_type>) {
+            construct_non_trivial(first, last);
+        }
+    }
+
+    void construct(iterator first, iterator last, const_reference proto) noexcept {
+        UTILS_NOUNROLL
+        while (first != last) {
+            storage_traits::construct(allocator(), first++, proto);
+        }
+    }
+
+    // should this be NOINLINE?
+    void construct_non_trivial(iterator first, iterator last) noexcept {
+        UTILS_NOUNROLL
+        while (first != last) {
+            storage_traits::construct(allocator(), first++);
+        }
+    }
+
+
+    inline void destroy(iterator first, iterator last) noexcept {
+        // we check for triviality here so that the implementation could be non-inline
+        if constexpr(!std::is_trivially_destructible_v<value_type>) {
+            destroy_non_trivial(first, last);
+        }
+    }
+
+    // should this be NOINLINE?
+    void destroy_non_trivial(iterator first, iterator last) noexcept {
+        UTILS_NOUNROLL
+        while (first != last) {
+            storage_traits::destroy(allocator(), --last);
+        }
+    }
+
+    // should this be NOINLINE?
+    void resize_non_trivial(size_type count) {
+        if (count > size()) {
+            construct(end(), begin() + count);
+        } else if (count < size()) {
+            destroy(begin() + count, end());
+        }
+        mSize = count;
+    }
+
+    // should this be NOINLINE?
+    void resize_non_trivial(size_type count, const_reference v) {
+        if (count > size()) {
+            construct(end(), begin() + count, v);
+        } else if (count < size()) {
+            destroy(begin() + count, end());
+        }
+        mSize = count;
+    }
+
+    // should this be NOINLINE?
+    void move_range(pointer s, pointer e, pointer to) {
+        if constexpr(std::is_trivially_copy_assignable_v<value_type>
+                && std::is_trivially_destructible_v<value_type>) {
+            // this generates memmove -- which doesn't happen otherwise
+            std::move_backward(s, e, to + std::distance(s, e));
+        } else {
+            pointer our_end = end();
+            difference_type n = our_end - to;   // nb of elements to move by operator=
+            pointer i = s + n;                  // 1st element to move by move ctor
+            for (pointer d = our_end ; i < our_end ; ++i, ++d) {
+                storage_traits::construct(allocator(), d, std::move(*i));
+            }
+            std::move_backward(s, s + n, our_end);
+        }
+    }
+
+    template<typename TYPE>
+    class SizeTypeWrapper {
+        TYPE value{};
+    public:
+        SizeTypeWrapper() noexcept = default;
+        SizeTypeWrapper(SizeTypeWrapper const& rhs) noexcept = default;
+        explicit  SizeTypeWrapper(TYPE value) noexcept : value(value) { }
+        SizeTypeWrapper& operator=(TYPE rhs) noexcept { value = rhs; return *this; }
+        SizeTypeWrapper& operator=(SizeTypeWrapper& rhs) noexcept = delete;
+        operator TYPE() const noexcept { return value; }
+    };
+
+    pointer mData{};
+    size_type mSize{};
+    compressed_pair<SizeTypeWrapper<size_type>, allocator_type> mCapacityAllocator{};
+};
+
+} // namespace utils
+
+#endif // TNT_UTILS_FIXEDCAPACITYVECTOR_H

flutter_filament/windows/include/filament/utils/Invocable.h

@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_INVOKABLE_H
+#define TNT_UTILS_INVOKABLE_H
+
+#include <type_traits>
+#include <utility>
+
+#include <assert.h>
+
+namespace utils {
+
+/*
+ * Invocable is a move-only general purpose function wrapper. Instances can
+ * store and invoke lambda expressions and other function objects.
+ *
+ * It is similar to std::function, with the following differences:
+ *  - Invocable is move only.
+ *  - Invocable can capture move only types.
+ *  - No conversion between 'compatible' functions.
+ *  - No small buffer optimization
+ */
+
+// Helper for enabling methods if Fn matches the function signature
+// requirements of the Invocable type.
+#if __cplusplus >= 201703L
+// only available on C++17 and up
+template<typename Fn, typename R, typename... Args>
+using EnableIfFnMatchesInvocable =
+        std::enable_if_t<std::is_invocable_v<Fn, Args...> &&
+                         std::is_same_v<R, std::invoke_result_t<Fn, Args...>>, int>;
+#else
+template<typename Fn, typename R, typename... Args>
+using EnableIfFnMatchesInvocable = std::enable_if_t<true, int>;
+#endif
+
+template<typename Signature>
+class Invocable;
+
+template<typename R, typename... Args>
+class Invocable<R(Args...)> {
+public:
+    // Creates an Invocable that does not contain a functor.
+    // Will evaluate to false.
+    Invocable() = default;
+
+    ~Invocable() noexcept;
+
+    // Creates an Invocable from the functor passed in.
+    template<typename Fn, EnableIfFnMatchesInvocable<Fn, R, Args...> = 0>
+    Invocable(Fn&& fn) noexcept; // NOLINT(google-explicit-constructor)
+
+    Invocable(const Invocable&) = delete;
+    Invocable(Invocable&& rhs) noexcept;
+
+    Invocable& operator=(const Invocable&) = delete;
+    Invocable& operator=(Invocable&& rhs) noexcept;
+
+    // Invokes the invocable with the args passed in.
+    // If the Invocable is empty, this will assert.
+    template<typename... OperatorArgs>
+    R operator()(OperatorArgs&& ... args);
+    template<typename... OperatorArgs>
+    R operator()(OperatorArgs&& ... args) const;
+
+    // Evaluates to true if Invocable contains a functor, false otherwise.
+    explicit operator bool() const noexcept;
+
+private:
+    void* mInvocable = nullptr;
+    void (*mDeleter)(void*) = nullptr;
+    R (* mInvoker)(void*, Args...) = nullptr;
+};
+
+template<typename R, typename... Args>
+template<typename Fn, EnableIfFnMatchesInvocable<Fn, R, Args...>>
+Invocable<R(Args...)>::Invocable(Fn&& fn) noexcept
+        : mInvocable(new Fn(std::forward<std::decay_t<Fn>>(fn))),
+          mDeleter(+[](void* erased_invocable) {
+              auto typed_invocable = static_cast<Fn*>(erased_invocable);
+              delete typed_invocable;
+          }),
+          mInvoker(+[](void* erased_invocable, Args... args) -> R {
+              auto typed_invocable = static_cast<Fn*>(erased_invocable);
+              return (*typed_invocable)(std::forward<Args>(args)...);
+          })
+{
+}
+
+template<typename R, typename... Args>
+Invocable<R(Args...)>::~Invocable() noexcept {
+    if (mDeleter) {
+        mDeleter(mInvocable);
+    }
+}
+
+template<typename R, typename... Args>
+Invocable<R(Args...)>::Invocable(Invocable&& rhs) noexcept
+        : mInvocable(rhs.mInvocable),
+          mDeleter(rhs.mDeleter),
+          mInvoker(rhs.mInvoker) {
+    rhs.mInvocable = nullptr;
+    rhs.mDeleter = nullptr;
+    rhs.mInvoker = nullptr;
+}
+
+template<typename R, typename... Args>
+Invocable<R(Args...)>& Invocable<R(Args...)>::operator=(Invocable&& rhs) noexcept {
+    if (this != &rhs) {
+        std::swap(mInvocable, rhs.mInvocable);
+        std::swap(mDeleter, rhs.mDeleter);
+        std::swap(mInvoker, rhs.mInvoker);
+    }
+    return *this;
+}
+
+template<typename R, typename... Args>
+template<typename... OperatorArgs>
+R Invocable<R(Args...)>::operator()(OperatorArgs&& ... args) {
+    assert(mInvoker && mInvocable);
+    return mInvoker(mInvocable, std::forward<OperatorArgs>(args)...);
+}
+
+template<typename R, typename... Args>
+template<typename... OperatorArgs>
+R Invocable<R(Args...)>::operator()(OperatorArgs&& ... args) const {
+    assert(mInvoker && mInvocable);
+    return mInvoker(mInvocable, std::forward<OperatorArgs>(args)...);
+}
+
+template<typename R, typename... Args>
+Invocable<R(Args...)>::operator bool() const noexcept {
+    return mInvoker != nullptr && mInvocable != nullptr;
+}
+
+} // namespace utils
+
+#endif // TNT_UTILS_INVOKABLE_H

flutter_filament/windows/include/filament/utils/Log.h

@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_LOG_H
+#define TNT_UTILS_LOG_H
+
+#include <utils/compiler.h>
+#include <utils/ostream.h>
+
+namespace utils {
+
+struct UTILS_PUBLIC Loggers {
+    // DEBUG level logging stream
+    io::ostream& d;
+
+    // ERROR level logging stream
+    io::ostream& e;
+
+    // WARNING level logging stream
+    io::ostream& w;
+
+    // INFORMATION level logging stream
+    io::ostream& i;
+
+    // VERBOSE level logging stream
+    io::ostream& v;
+};
+
+extern UTILS_PUBLIC Loggers const slog;
+
+} // namespace utils
+
+#endif // TNT_UTILS_LOG_H

flutter_filament/windows/include/filament/utils/Mutex.h

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_MUTEX_H
+#define TNT_UTILS_MUTEX_H
+
+#if defined(__ANDROID__)
+#include <utils/linux/Mutex.h>
+#else
+#include <utils/generic/Mutex.h>
+#endif
+
+#endif // TNT_UTILS_MUTEX_H

flutter_filament/windows/include/filament/utils/NameComponentManager.h

@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_NAMECOMPONENTMANAGER_H
+#define TNT_UTILS_NAMECOMPONENTMANAGER_H
+
+#include <utils/compiler.h>
+#include <utils/CString.h>
+#include <utils/Entity.h>
+#include <utils/EntityInstance.h>
+#include <utils/SingleInstanceComponentManager.h>
+
+#include <stddef.h>
+#include <stdint.h>
+
+namespace utils {
+
+class EntityManager;
+
+/**
+ * \class NameComponentManager NameComponentManager.h utils/NameComponentManager.h
+ * \brief Allows clients to associate string labels with entities.
+ *
+ * To access the name of an existing entity, clients should first use NameComponentManager to get a
+ * temporary handle called an \em instance. Please note that instances are ephemeral; clients should
+ * store entities, not instances.
+ *
+ * Usage example:
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ * auto names = new NameComponentManager(EntityManager::get());
+ * names->addComponent(myEntity);
+ * names->setName(names->getInstance(myEntity), "Jeanne d'Arc");
+ * ...
+ * printf("%s\n", names->getName(names->getInstance(myEntity));
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+class UTILS_PUBLIC NameComponentManager : public SingleInstanceComponentManager<utils::CString> {
+public:
+    using Instance = EntityInstance<NameComponentManager>;
+
+    /**
+     * Creates a new name manager associated with the given entity manager.
+     *
+     * Note that multiple string labels could be associated with each entity simply by
+     * creating multiple instances of NameComponentManager.
+     */
+    explicit NameComponentManager(EntityManager& em);
+    ~NameComponentManager();
+
+    /**
+     * Checks if the given entity already has a name component.
+     */
+    using SingleInstanceComponentManager::hasComponent;
+
+    /**
+     * Gets a temporary handle that can be used to access the name.
+     *
+     * @return Non-zero handle if the entity has a name component, 0 otherwise.
+     */
+    Instance getInstance(Entity e) const noexcept {
+        return { SingleInstanceComponentManager::getInstance(e) };
+    }
+
+    /*! \cond PRIVATE */
+    // these are implemented in SingleInstanceComponentManager<>, but we need to
+    // reimplement them in each manager, to ensure they are generated in an implementation file
+    // for backward binary compatibility reasons.
+    size_t getComponentCount() const noexcept;
+    Entity const* getEntities() const noexcept;
+    void gc(const EntityManager& em, size_t ratio = 4) noexcept;
+    /*! \endcond */
+
+    /**
+     * Adds a name component to the given entity if it doesn't already exist.
+     */
+    void addComponent(Entity e);
+
+    /**
+     * Removes the name component to the given entity if it exists.
+     */
+    void removeComponent(Entity e);
+
+    /**
+     * Stores a copy of the given string and associates it with the given instance.
+     */
+    void setName(Instance instance, const char* name) noexcept;
+
+    /**
+     * Retrieves the string associated with the given instance, or nullptr if none exists.
+     *
+     * @return pointer to the copy that was made during setName()
+     */
+    const char* getName(Instance instance) const noexcept;
+};
+
+} // namespace utils
+
+#endif // TNT_UTILS_NAMECOMPONENTMANAGER_H

flutter_filament/windows/include/filament/utils/Panic.h

@@ -0,0 +1,563 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_PANIC_H
+#define TNT_UTILS_PANIC_H
+
+#include <string>
+
+#include <utils/CallStack.h>
+#include <utils/compiler.h>
+
+#ifdef __EXCEPTIONS
+#   define UTILS_EXCEPTIONS 1
+#else
+#endif
+
+/**
+ * @defgroup errors Handling Catastrophic Failures (Panics)
+ *
+ * @brief Failure detection and reporting facilities
+ *
+ * ## What's a Panic? ##
+ *
+ * In the context of this document, a _panic_ is a type of error due to a _contract violation_,
+ * it shouldn't be confused with a _result_ or _status_ code. The POSIX API for instance,
+ * unfortunately often conflates the two.
+ * @see <http://en.wikipedia.org/wiki/Design_by_contract>
+ *
+ *
+ * Here we give the following definition of a _panic_:
+ *
+ *   1. Failures to meet a function's own **postconditions**\n
+ *      The function cannot establish one of its own postconditions, such as (but not limited to)
+ *      producing a valid return value object.
+ *
+ *      Often these failures are only detectable at runtime, for instance they can be caused by
+ *      arithmetic errors, as it was the case for the Ariane 5 rocket. Ariane 5 crashed because it
+ *      reused an inertial module from Ariane 4, which didn't account for the greater horizontal
+ *      acceleration of Ariane 5 and caused an overflow in the computations. Ariane 4's module
+ *      wasn't per-say buggy, but was improperly used and failed to meet, obviously, certain
+ *      postconditions.
+ *      @see <http://en.wikipedia.org/wiki/Cluster_(spacecraft)>
+ *
+ *   2. Failures to meet the **preconditions** of any of a function's callees\n
+ *      The function cannot meet a precondition of another function it must call, such as a
+ *      restriction on a parameter.
+ *
+ *      Not to be confused with the case where the preconditions of a function are already
+ *      violated upon entry, which indicates a programming error from the caller.
+ *
+ *      Typically these failures can be avoided and arise because of programming errors.
+ *
+ * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ * ## Failure reporting vs. handling ##
+ *
+ * Very often when a panic, as defined above, is detected, the program has little other choice
+ * but to terminate.\n
+ * Typically these situations can be handled by _assert()_. However, _assert()_ also conflates two
+ * very different concepts: detecting and handling failures.\n
+ * The place where a failure is detected is rarely the place where there is enough
+ * context to decide what to do. _assert()_ terminates the program which, may or may not be
+ * appropriate. At the very least the failure must be logged (which _assert()_ does in a crude way),
+ * but some other actions might need to happen, such as:\n
+ *
+ *   - logging the failure in the system-wide logger
+ *   - providing enough information in development builds to analyze/debug the problem
+ *   - cleanly releasing some resources, such as communication channels with other processes\n
+ *     e.g.: to avoid their pre- or postconditions from being violated as well.
+ *
+ * In some _rare_ cases, the failure might even be ignored altogether because it doesn't matter in
+ * the context where it happened. This decision clearly doesn't always lie at the failure-site.
+ *
+ * It is therefore important to separate failure detection from handling.
+ *
+ *
+ * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ * ## Failure detection and handling facilities ##
+ *
+ * Clearly, catastrophic failures should be **rare**; in fact they should
+ * never happen, except possibly for "failures to meet a function's own postconditions", which
+ * may depend on external factors and should still be very rare. Yet, when a failure happens, it
+ * must be detected and handled appropriately.\n
+ * Since panics are rare, it is desirable that the handling mechanism be as unobtrusive
+ * as possible, without allowing such failures to go unnoticed or swallowed by mistake. Ideally, the
+ * programmer using an API should have nothing special to do to handle that API's failure
+ * conditions.\n\n
+ *
+ * An important feature of the Panic Handling facilities here is that **panics are not part of
+ * the API of a function or method**\n\n
+ *
+ *
+ * The panic handling facility has the following benefits:
+ *   - provides an easy way to detect and report failure
+ *   - separates failure detection from handling
+ *   - makes it hard for detected failures to be ignored (i.e.: not handled)
+ *   - doesn't add burden on the API design
+ *   - doesn't add overhead (visual or otherwise) at call sites
+ *   - has very little performance overhead for failure detection
+ *   - has little to no performance impact for failure handling in the common (success) case
+ *   - is flexible and extensible
+ *
+ * Since we have established that failures are **rare**, **exceptional** situations, it would be
+ * appropriate to handle them with an _assert_ mechanism and that's what the API below
+ * provides. However, under-the-hood it uses C++ exceptions as a means to separate
+ * _reporting_ from _handling_.
+ *
+ *   \note On devices where exceptions are not supported or appropriate, these APIs can be turned
+ *   into a regular _std::terminate()_.
+ *
+ *
+ *          ASSERT_PRECONDITION(condition, format, ...)
+ *          ASSERT_POSTCONDITION(condition, format, ...)
+ *          ASSERT_ARITHMETIC(condition, format, ...)
+ *          ASSERT_DESTRUCTOR(condition, format, ...)
+ *
+ *
+ * @see ASSERT_PRECONDITION, ASSERT_POSTCONDITION, ASSERT_ARITHMETIC
+ * @see ASSERT_DESTRUCTOR
+ *
+ * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ * ## Writing code that can assert ##
+ *
+ * Because we've separated failure reporting from failure handling, there are some considerations
+ * that need to be thought about when writing code that calls the macros above (i.e.: the program
+ * won't terminate at the point where the failure is detected).\n\n
+ *
+ *
+ * ### Panic guarantees ###
+ *
+ * After the failure condition is reported by a function, additional guarantees may be provided
+ * with regards to the state of the program. The following four levels of guarantee are
+ * generally recognized, each of which is a strict superset of its successors:
+ *
+ *  1. Nothrow exception guarantee\n
+ *     The function never asserts. e.g.: This should always be the case with destructors.\n\n
+ *
+ *  2. Strong exception guarantee\n
+ *     If the function asserts, the state of the program is rolled back to the state just before
+ *     the function call.\n\n
+ *
+ *  3. Basic exception guarantee\n
+ *     If the function asserts, the program is in a valid state. It may require cleanup,
+ *     but all invariants are intact.\n\n
+ *
+ *  4. No exception guarantee\n
+ *     If the function asserts, the program may not be in a valid state: resource leaks, memory
+ *     corruption, or other invariant-destroying failures may have occurred.
+ *
+ * In each function, give the **strongest** safety guarantee that won't penalize callers who
+ * don't need it, but **always give at least the basic guarantee**. The RAII (Resource
+ * Acquisition Is Initialization) pattern can help with achieving these guarantees.
+ *
+ * @see [RAII](http://en.wikipedia.org/wiki/Resource_Acquisition_Is_Initialization)
+ *
+ * ### Special considerations for Constructors ###
+ *
+ * Constructors are a bit special because if a failure occurs during their execution, the
+ * destructor won't be called (how could it? since the object wasn't constructed!). This can lead
+ * to leaked resources allocated in the constructor prior to the failure. Thankfully there is
+ * a nice C++ syntax to handle this case:
+ *
+ * @code
+ *          Foo::Foo(size_t s) try : m_size(s), m_buf(new uint32_t[s]) {
+ *              ASSERT_POSTCONDITION(s&0xF==0,
+ *                  "object size is %u, but must be multiple of 16", s);
+ *          } catch (...) {
+ *              delete [] m_buf;
+ *              // the exception will be automatically re-thrown
+ *          }
+ * @endcode
+ *
+ * Unfortunately, this usage leaks the underlying, exception-based, implementation of the
+ * panic handling macros. For this reason, it is best to keep constructors simple and guarantee
+ * they can't fail. An _init()_ function with a factory can be used for actual initialization.
+ *
+ *
+ * ### Special considerations for Destructors ###
+ *
+ * In C++ destructors cannot throw exceptions and since the above macros internally use exceptions
+ * they cannot be used in destructors. Doing so will result in immediate termination of the
+ * program by _std::terminate()_.\n
+ * It is therefore best to always guarantee that destructors won't fail. In case of such a
+ * failure in a destructor the ASSERT_DESTRUCTOR() macro can be used instead, it
+ * will log the failure but won't terminate the program, instead it'll proceed as if nothing
+ * happened. Generally this will result in some resource leak which, eventually, will cause
+ * another failure (typically a postcondition violation).\n\n
+ *
+ * Rationale for this behavior: There are fundamentally no way to report a failure from a
+ * destructor in C++, violently terminating the process is inadequate because it again conflates
+ * failure reporting and failure handling; for instance a failure in glDeleteTextures() shouldn't
+ * be necessarily fatal (certainly not without saving the user's data first). The alternative
+ * would be for the caller to swallow the failure entirely, but that's not great either because the
+ * failure would go unnoticed. The solution retained here is a compromise.
+ *
+ * @see ASSERT_DESTRUCTOR
+ *
+ * ### Testing Code that Uses Panics ###
+ *
+ * Since panics use exceptions for their underlying implementation, you can test code that uses
+ * panics with EXPECT_THROW by doing the following things:
+ * \li Set panic mode to THROW (default is TERMINATE)
+ * \li Pass Panic to EXPECT_THROW as the exception type
+ *
+ * Example code for your test file:
+ *
+ * @code
+ * #include <MyClass.hpp>  // since your code uses panics, this should include utils/Panic.hpp
+ *
+ * using utils::Panic;
+ *
+ * TEST(MyClassTest, value_that_causes_panic) {
+ *     EXPECT_THROW(MyClass::function(value_that_causes_panic), Panic);
+ * }
+ *
+ * // ... other tests ...
+ *
+ * int main(int argc, char** argv) {
+ *     ::testing::InitGoogleTest(&argc, argv);
+ *     Panic::setMode(Panic::Mode::THROW);
+ *     return RUN_ALL_TESTS();
+ * }
+ * @endcode
+ *
+ */
+
+namespace utils {
+
+// -----------------------------------------------------------------------------------------------
+
+/**
+ * @ingroup errors
+ *
+ * \brief Base class of all exceptions thrown by all the ASSERT macros
+ *
+ * The Panic class provides the std::exception protocol, it is the base exception object
+ * used for all thrown exceptions.
+ */
+class UTILS_PUBLIC Panic {
+public:
+    virtual ~Panic() noexcept;
+
+    /**
+     * @return a detailed description of the error
+     * @see std::exception
+     */
+    virtual const char* what() const noexcept = 0;
+
+    /**
+     * Get the function name where the panic was detected
+     * @return a C string containing the function name where the panic was detected
+     */
+    virtual const char* getFunction() const noexcept = 0;
+
+    /**
+     * Get the file name where the panic was detected
+     * @return a C string containing the file name where the panic was detected
+     */
+    virtual const char* getFile() const noexcept = 0;
+
+    /**
+     * Get the line number in the file where the panic was detected
+     * @return an integer containing the line number in the file where the panic was detected
+     */
+    virtual int getLine() const noexcept = 0;
+
+    /**
+     * Logs this exception to the system-log
+     */
+    virtual void log() const noexcept = 0;
+
+    /**
+     * Get the CallStack when the panic was detected
+     * @return the CallStack when the panic was detected
+     */
+    virtual const CallStack& getCallStack() const noexcept = 0;
+};
+
+// -----------------------------------------------------------------------------------------------
+
+/**
+ * @ingroup errors
+ *
+ * \brief Concrete implementation of the Panic interface.
+ *
+ * The TPanic<> class implements the std::exception protocol as well as the Panic
+ * interface common to all exceptions thrown by the framework.
+ */
+template <typename T>
+class UTILS_PUBLIC TPanic : public Panic {
+public:
+    // std::exception protocol
+    const char* what() const noexcept override;
+
+    // Panic interface
+    const char* getFunction() const noexcept override;
+    const char* getFile() const noexcept override;
+    int getLine() const noexcept override;
+    const CallStack& getCallStack() const noexcept override;
+    void log() const noexcept override;
+
+    /**
+     * Depending on the mode set, either throws an exception of type T with the given reason plus
+     * extra information about the error-site, or logs the error and calls std::terminate().
+     * This function never returns.
+     * @param function the name of the function where the error was detected
+     * @param file the file where the above function in implemented
+     * @param line the line in the above file where the error was detected
+     * @param format printf style string describing the error
+     * @see ASSERT_PRECONDITION, ASSERT_POSTCONDITION, ASSERT_ARITHMETIC
+     * @see PANIC_PRECONDITION, PANIC_POSTCONDITION, PANIC_ARITHMETIC
+     * @see setMode()
+     */
+    static void panic(char const* function, char const* file, int line, const char* format, ...)
+        UTILS_NORETURN;
+
+    /**
+     * Depending on the mode set, either throws an exception of type T with the given reason plus
+     * extra information about the error-site, or logs the error and calls std::terminate().
+     * This function never returns.
+     * @param function the name of the function where the error was detected
+     * @param file the file where the above function in implemented
+     * @param line the line in the above file where the error was detected
+     * @param s std::string describing the error
+     * @see ASSERT_PRECONDITION, ASSERT_POSTCONDITION, ASSERT_ARITHMETIC
+     * @see PANIC_PRECONDITION, PANIC_POSTCONDITION, PANIC_ARITHMETIC
+     * @see setMode()
+     */
+    static inline void panic(char const* function, char const* file, int line, const std::string& s)
+        UTILS_NORETURN {
+        panic(function, file, line, s.c_str());
+    }
+
+protected:
+    /**
+     * Creates a Panic.
+     * @param reason a description of the cause of the error
+     */
+    explicit TPanic(std::string reason);
+
+    /**
+     * Creates a Panic with extra information about the error-site.
+     * @param function the name of the function where the error was detected
+     * @param file the file where the above function in implemented
+     * @param line the line in the above file where the error was detected
+     * @param reason a description of the cause of the error
+     */
+    TPanic(char const* function, char const* file, int line, std::string reason);
+
+    ~TPanic() override;
+
+private:
+    void buildMessage();
+
+    CallStack m_callstack;
+    std::string m_reason;
+    char const* const m_function = nullptr;
+    char const* const m_file = nullptr;
+    const int m_line = -1;
+    mutable std::string m_msg;
+};
+
+namespace details {
+// these are private, don't use
+void panicLog(
+        char const* function, char const* file, int line, const char* format, ...) noexcept;
+}  // namespace details
+
+// -----------------------------------------------------------------------------------------------
+
+/**
+ * @ingroup errors
+ *
+ * ASSERT_PRECONDITION uses this Panic to report a precondition failure.
+ * @see ASSERT_PRECONDITION
+ */
+class UTILS_PUBLIC PreconditionPanic : public TPanic<PreconditionPanic> {
+    // Programming error, can be avoided
+    // e.g.: invalid arguments
+    using TPanic<PreconditionPanic>::TPanic;
+    friend class TPanic<PreconditionPanic>;
+};
+
+/**
+ * @ingroup errors
+ *
+ * ASSERT_POSTCONDITION uses this Panic to report a postcondition failure.
+ * @see ASSERT_POSTCONDITION
+ */
+class UTILS_PUBLIC PostconditionPanic : public TPanic<PostconditionPanic> {
+    // Usually only detectable at runtime
+    // e.g.: dead-lock would occur, arithmetic errors
+    using TPanic<PostconditionPanic>::TPanic;
+    friend class TPanic<PostconditionPanic>;
+};
+
+/**
+ * @ingroup errors
+ *
+ * ASSERT_ARITHMETIC uses this Panic to report an arithmetic (postcondition) failure.
+ * @see ASSERT_ARITHMETIC
+ */
+class UTILS_PUBLIC ArithmeticPanic : public TPanic<ArithmeticPanic> {
+    // A common case of post-condition error
+    // e.g.: underflow, overflow, internal computations errors
+    using TPanic<ArithmeticPanic>::TPanic;
+    friend class TPanic<ArithmeticPanic>;
+};
+
+// -----------------------------------------------------------------------------------------------
+}  // namespace utils
+
+#ifndef NDEBUG
+#   define PANIC_FILE(F) (F)
+#   define PANIC_FUNCTION __PRETTY_FUNCTION__
+#else
+#   define PANIC_FILE(F) ""
+#   define PANIC_FUNCTION __func__
+#endif
+
+/**
+ * PANIC_PRECONDITION is a macro that reports a PreconditionPanic
+ * @param format printf-style string describing the error in more details
+ */
+#define PANIC_PRECONDITION(format, ...)                                                            \
+    ::utils::PreconditionPanic::panic(PANIC_FUNCTION,                                              \
+            PANIC_FILE(__FILE__), __LINE__, format, ##__VA_ARGS__)
+
+/**
+ * PANIC_POSTCONDITION is a macro that reports a PostconditionPanic
+ * @param format printf-style string describing the error in more details
+ */
+#define PANIC_POSTCONDITION(format, ...)                                                           \
+    ::utils::PostconditionPanic::panic(PANIC_FUNCTION,                                             \
+            PANIC_FILE(__FILE__), __LINE__, format, ##__VA_ARGS__)
+
+/**
+ * PANIC_ARITHMETIC is a macro that reports a ArithmeticPanic
+ * @param format printf-style string describing the error in more details
+ */
+#define PANIC_ARITHMETIC(format, ...)                                                              \
+    ::utils::ArithmeticPanic::panic(PANIC_FUNCTION,                                                \
+            PANIC_FILE(__FILE__), __LINE__, format, ##__VA_ARGS__)
+
+/**
+ * PANIC_LOG is a macro that logs a Panic, and continues as usual.
+ * @param format printf-style string describing the error in more details
+ */
+#define PANIC_LOG(format, ...)                                                                     \
+    ::utils::details::panicLog(PANIC_FUNCTION,                                                     \
+            PANIC_FILE(__FILE__), __LINE__, format, ##__VA_ARGS__)
+
+/**
+ * @ingroup errors
+ *
+ * ASSERT_PRECONDITION is a macro that checks the given condition and reports a PreconditionPanic
+ * if it evaluates to false.
+ * @param cond a boolean expression
+ * @param format printf-style string describing the error in more details
+ */
+#define ASSERT_PRECONDITION(cond, format, ...)                                                     \
+    (!UTILS_LIKELY(cond) ? PANIC_PRECONDITION(format, ##__VA_ARGS__) : (void)0)
+
+#if defined(UTILS_EXCEPTIONS) || !defined(NDEBUG)
+#define ASSERT_PRECONDITION_NON_FATAL(cond, format, ...)                                           \
+    (!UTILS_LIKELY(cond) ? PANIC_PRECONDITION(format, ##__VA_ARGS__), false : true)
+#else
+#define ASSERT_PRECONDITION_NON_FATAL(cond, format, ...)                                           \
+    (!UTILS_LIKELY(cond) ? PANIC_LOG(format, ##__VA_ARGS__), false : true)
+#endif
+
+
+/**
+ * @ingroup errors
+ *
+ * ASSERT_POSTCONDITION is a macro that checks the given condition and reports a PostconditionPanic
+ * if it evaluates to false.
+ * @param cond a boolean expression
+ * @param format printf-style string describing the error in more details
+ *
+ * Example:
+ * @code
+ *     int& Foo::operator[](size_t index) {
+ *         ASSERT_POSTCONDITION(index<m_size, "cannot produce a valid return value");
+ *         return m_array[index];
+ *     }
+ * @endcode
+ */
+#define ASSERT_POSTCONDITION(cond, format, ...)                                                    \
+    (!UTILS_LIKELY(cond) ? PANIC_POSTCONDITION(format, ##__VA_ARGS__) : (void)0)
+
+#if defined(UTILS_EXCEPTIONS) || !defined(NDEBUG)
+#define ASSERT_POSTCONDITION_NON_FATAL(cond, format, ...)                                          \
+    (!UTILS_LIKELY(cond) ? PANIC_POSTCONDITION(format, ##__VA_ARGS__), false : true)
+#else
+#define ASSERT_POSTCONDITION_NON_FATAL(cond, format, ...)                                          \
+    (!UTILS_LIKELY(cond) ? PANIC_LOG(format, ##__VA_ARGS__), false : true)
+#endif
+
+/**
+ * @ingroup errors
+ *
+ * ASSERT_ARITHMETIC is a macro that checks the given condition and reports a ArithmeticPanic
+ * if it evaluates to false.
+ * @param cond a boolean expression
+ * @param format printf-style string describing the error in more details
+ *
+ * Example:
+ * @code
+ *     unt32_t floatToUInt1616(float v) {
+ *         v *= 65536;
+ *         ASSERT_ARITHMETIC(v>=0 && v<65536, "overflow occurred");
+ *         return uint32_t(v);
+ *     }
+ * @endcode
+ */
+#define ASSERT_ARITHMETIC(cond, format, ...)                                                       \
+    (!(cond) ? PANIC_ARITHMETIC(format, ##__VA_ARGS__) : (void)0)
+
+#if defined(UTILS_EXCEPTIONS) || !defined(NDEBUG)
+#define ASSERT_ARITHMETIC_NON_FATAL(cond, format, ...)                                             \
+    (!UTILS_LIKELY(cond) ? PANIC_ARITHMETIC(format, ##__VA_ARGS__), false : true)
+#else
+#define ASSERT_ARITHMETIC_NON_FATAL(cond, format, ...)                                             \
+    (!UTILS_LIKELY(cond) ? PANIC_LOG(format, ##__VA_ARGS__), false : true)
+#endif
+
+/**
+ * @ingroup errors
+ *
+ * ASSERT_DESTRUCTOR is a macro that checks the given condition and logs an error
+ * if it evaluates to false.
+ * @param cond a boolean expression
+ * @param format printf-style string describing the error in more details
+ *
+ * @warning Use this macro if a destructor can fail, which should be avoided at all costs.
+ * Unlike the other ASSERT macros, this will never result in the process termination. Instead,
+ * the error will be logged and the program will continue as if nothing happened.
+ *
+ * Example:
+ * @code
+ *     Foo::~Foo() {
+ *        glDeleteTextures(1, &m_texture);
+ *        GLint err = glGetError();
+ *        ASSERT_DESTRUCTOR(err == GL_NO_ERROR, "cannot free GL resource!");
+ *     }
+ * @endcode
+ */
+#define ASSERT_DESTRUCTOR(cond, format, ...) (!(cond) ? PANIC_LOG(format, ##__VA_ARGS__) : (void)0)
+
+#endif  // TNT_UTILS_PANIC_H

flutter_filament/windows/include/filament/utils/Path.h

@@ -0,0 +1,297 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_PATH_H
+#define TNT_UTILS_PATH_H
+
+#include <utils/compiler.h>
+
+#include <iosfwd>
+#include <string>
+#include <vector>
+
+namespace utils {
+
+/**
+ * An abstract representation of file and directory paths.
+ */
+class UTILS_PUBLIC Path {
+public:
+    /**
+     * Creates a new empty path.
+     */
+    Path() = default;
+    ~Path() = default;
+
+    /**
+     * Creates a new path with the specified pathname.
+     *
+     * @param pathname a non-null pathname string
+     */
+    Path(const char* pathname);
+
+    /**
+     * Creates a new path with the specified pathname.
+     *
+     * @param pathname a pathname string view
+     */
+    Path(std::string_view pathname);
+
+    /**
+     * Creates a new path with the specified pathname.
+     *
+     * @param pathname a pathname string
+     */
+    Path(const std::string& pathname);
+
+    /**
+     * Tests whether the file or directory denoted by this abstract
+     * pathname exists.
+     *
+     * @return true if the file or directory denoted by this
+     *         abstract pathname exists, false otherwise
+     */
+    bool exists() const;
+
+    /**
+     * Tests whether this abstract pathname represents a regular file.
+     * This method can only return true if the path exists.
+     *
+     * @return true if this pathname represents an existing file,
+     *         false if the path doesn't exist or represents something
+     *         else (directory, symlink, etc.)
+     */
+    bool isFile() const;
+
+    /**
+     * Tests whether this abstract pathname represents a directory.
+     * This method can only return true if the path exists.
+     *
+     * @return true if this pathname represents an existing directory,
+     *         false if the path doesn't exist or represents a file
+     */
+    bool isDirectory() const;
+
+    /**
+     * Tests whether this path is empty. An empty path does not
+     * exist.
+     *
+     * @return true if the underlying abstract pathname is empty,
+     *         false otherwise
+     */
+    bool isEmpty() const { return m_path.empty(); }
+
+    const char* c_str() const { return m_path.c_str(); }
+
+    /**
+     * Replaces the abstract pathname of this object with the
+     * specified pathname.
+     *
+     * @param pathname a pathname string
+     */
+    void setPath(const std::string& pathname) {
+        m_path = getCanonicalPath(pathname);
+    }
+
+    /**
+     * @return the canonical pathname this path represents
+     */
+    const std::string& getPath() const { return m_path; }
+
+    /**
+     * Returns the parent of this path as Path.
+     * @return a new path containing the parent of this path
+     */
+    Path getParent() const;
+
+    /**
+     * Returns ancestor path where "0" is the immediate parent.
+     * @return a new path containing the ancestor of this path
+     */
+    Path getAncestor(int n) const;
+
+    /**
+     * Returns the name of the file or directory represented by
+     * this abstract pathname.
+     *
+     * @return the name of the file or directory represented by
+     *         this abstract pathname, or an empty string if
+     *         this path is empty
+     */
+    std::string getName() const;
+
+    /**
+     * Returns the name of the file or directory represented by
+     * this abstract pathname without its extension.
+     *
+     * @return the name of the file or directory represented by
+     *         this abstract pathname, or an empty string if
+     *         this path is empty
+     */
+    std::string getNameWithoutExtension() const;
+
+    /**
+     * Returns the file extension (after the ".") if one is present.
+     * Returns the empty string if no filename is present or if the
+     * path is a directory.
+     *
+     * @return the file extension (if one is present and
+     *         this is not a directory), else the empty string.
+     */
+    std::string getExtension() const;
+
+    /**
+     * Returns the absolute representation of this path.
+     * If this path's pathname starts with a leading '/',
+     * the returned path is equal to this path. Otherwise,
+     * this path's pathname is concatenated with the current
+     * working directory and the result is returned.
+     *
+     * @return a new path containing the absolute representation
+     *         of this path
+     */
+    Path getAbsolutePath() const;
+
+    /**
+     * @return true if this abstract pathname is not empty
+     *         and starts with a leading '/', false otherwise
+     */
+    bool isAbsolute() const;
+
+    /**
+     * Splits this object's abstract pathname in a vector of file
+     * and directory name. If the underlying abstract pathname
+     * starts with a '/', the returned vector's first element
+     * will be the string "/".
+     *
+     * @return a vector of strings, empty if this path is empty
+     */
+    std::vector<std::string> split() const;
+
+    /**
+     * Concatenates the specified path with this path in a new
+     * path object.
+     *
+     * @note if the pathname to concatenate with starts with
+     * a leading '/' then that pathname is returned without
+     * being concatenated to this object's pathname.
+     *
+     * @param path the path to concatenate with
+     *
+     * @return the concatenation of the two paths
+     */
+    Path concat(const Path& path) const;
+
+    /**
+     * Concatenates the specified path with this path and
+     * stores the result in this path.
+     *
+     * @note if the pathname to concatenate with starts with
+     * a leading '/' then that pathname replaces this object's
+     * pathname.
+     *
+     * @param path the path to concatenate with
+     */
+    void concatToSelf(const Path& path);
+
+    operator std::string const&() const { return m_path; }
+
+    Path operator+(const Path& rhs) const { return concat(rhs); }
+    Path& operator+=(const Path& rhs) {
+        concatToSelf(rhs);
+        return *this;
+    }
+
+    bool operator==(const Path& rhs) const { return m_path == rhs.m_path; }
+    bool operator!=(const Path& rhs) const { return m_path != rhs.m_path; }
+
+    bool operator<(const Path& rhs) const { return m_path < rhs.m_path; }
+    bool operator>(const Path& rhs) const { return m_path > rhs.m_path; }
+
+    friend std::ostream& operator<<(std::ostream& os, const Path& path);
+
+    /**
+     * Returns a canonical copy of the specified pathname by removing
+     * unnecessary path segments such as ".", ".." and "/".
+     *
+     * @param pathname a pathname string
+     *
+     * @return the canonical representation of the specified pathname
+     */
+    static std::string getCanonicalPath(const std::string& pathname);
+
+    /**
+     * This method is equivalent to calling root.concat(leaf).
+     */
+    static Path concat(const std::string& root, const std::string& leaf);
+
+    /**
+     * @return a path representing the current working directory
+     */
+    static Path getCurrentDirectory();
+
+    /**
+     * @return a path representing the current executable
+     */
+    static Path getCurrentExecutable();
+
+    /**
+     * @return a path representing a directory where temporary files can be stored
+     */
+    static Path getTemporaryDirectory();
+
+    /**
+     * Creates a directory denoted by the given path.
+     * This is not recursive and doesn't create intermediate directories.
+     *
+     * @return True if directory was successfully created.
+     *         When false, errno should have details on actual error.
+     */
+    bool mkdir() const;
+
+    /**
+     * Creates a directory denoted by the given path.
+     * This is recursive and parent directories will be created if they do not
+     * exist.
+     *
+     * @return True if directory was successfully created or already exists.
+     *         When false, errno should have details on actual error.
+     */
+    bool mkdirRecursive() const;
+
+    /**
+     * Deletes this file.
+     *
+     * @return True if file was successfully deleted.
+     *         When false, errno should have details on actual error.
+     */
+    bool unlinkFile();
+
+    /**
+    * Lists the contents of this directory, skipping hidden files.
+    *
+    * @return A vector of paths of the contents of the directory.  If the path points to a file,
+    *         nonexistent directory, or empty directory, an empty vector is returned.
+    */
+    std::vector<Path> listContents() const;
+
+private:
+    std::string m_path;
+};
+
+} // namespace utils
+
+#endif // TNT_UTILS_PATH_H

flutter_filament/windows/include/filament/utils/PrivateImplementation-impl.h

@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef UTILS_PRIVATEIMPLEMENTATION_IMPL_H
+#define UTILS_PRIVATEIMPLEMENTATION_IMPL_H
+
+/*
+ * This looks like a header file, but really it acts as a .cpp, because it's used to
+ * explicitly instantiate the methods of PrivateImplementation<>
+ */
+
+#include <utils/PrivateImplementation.h>
+
+#include <utility>
+
+namespace utils {
+
+template<typename T>
+PrivateImplementation<T>::PrivateImplementation() noexcept
+        : mImpl(new T) {
+}
+
+template<typename T>
+template<typename ... ARGS>
+PrivateImplementation<T>::PrivateImplementation(ARGS&& ... args) noexcept
+        : mImpl(new T(std::forward<ARGS>(args)...)) {
+}
+
+template<typename T>
+PrivateImplementation<T>::~PrivateImplementation() noexcept {
+    delete mImpl;
+}
+
+#ifndef UTILS_PRIVATE_IMPLEMENTATION_NON_COPYABLE
+
+template<typename T>
+PrivateImplementation<T>::PrivateImplementation(PrivateImplementation const& rhs) noexcept
+        : mImpl(new T(*rhs.mImpl)) {
+}
+
+template<typename T>
+PrivateImplementation<T>& PrivateImplementation<T>::operator=(PrivateImplementation<T> const& rhs) noexcept {
+    if (this != &rhs) {
+        *mImpl = *rhs.mImpl;
+    }
+    return *this;
+}
+
+#endif
+
+} // namespace utils
+
+#endif // UTILS_PRIVATEIMPLEMENTATION_IMPL_H

flutter_filament/windows/include/filament/utils/PrivateImplementation.h

@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef UTILS_PRIVATEIMPLEMENTATION_H
+#define UTILS_PRIVATEIMPLEMENTATION_H
+
+#include <utils/compiler.h>
+
+#include <stddef.h>
+
+namespace utils {
+
+/**
+ * \privatesection
+ * PrivateImplementation is used to hide the implementation details of a class and ensure a higher
+ * level of backward binary compatibility.
+ * The actual implementation is in src/PrivateImplementation-impl.h"
+ */
+template<typename T>
+class PrivateImplementation {
+public:
+    // none of these methods must be implemented inline because it's important that their
+    // implementation be hidden from the public headers.
+    template<typename ... ARGS>
+    explicit PrivateImplementation(ARGS&& ...) noexcept;
+    PrivateImplementation() noexcept;
+    ~PrivateImplementation() noexcept;
+    PrivateImplementation(PrivateImplementation const& rhs) noexcept;
+    PrivateImplementation& operator = (PrivateImplementation const& rhs) noexcept;
+
+    // move ctor and copy operator can be implemented inline and don't need to be exported
+    PrivateImplementation(PrivateImplementation&& rhs) noexcept : mImpl(rhs.mImpl) { rhs.mImpl = nullptr; }
+    PrivateImplementation& operator = (PrivateImplementation&& rhs) noexcept {
+        auto temp = mImpl;
+        mImpl = rhs.mImpl;
+        rhs.mImpl = temp;
+        return *this;
+    }
+
+protected:
+    T* mImpl = nullptr;
+    inline T* operator->() noexcept { return mImpl; }
+    inline T const* operator->() const noexcept { return mImpl; }
+};
+
+} // namespace utils
+
+#endif // UTILS_PRIVATEIMPLEMENTATION_H

flutter_filament/windows/include/filament/utils/SingleInstanceComponentManager.h

@@ -0,0 +1,318 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_SINGLEINSTANCECOMPONENTMANAGER_H
+#define TNT_UTILS_SINGLEINSTANCECOMPONENTMANAGER_H
+
+#include <utils/compiler.h>
+#include <utils/Entity.h>
+#include <utils/EntityInstance.h>
+#include <utils/EntityManager.h>
+#include <utils/StructureOfArrays.h>
+
+#include <tsl/robin_map.h>
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
+
+namespace utils {
+
+class EntityManager;
+
+/*
+ * Helper class to create single instance component managers.
+ *
+ * This handles the component's storage as a structure-of-arrays, as well
+ * as the garbage collection.
+ *
+ * This is intended to be used as base class for a real component manager. When doing so,
+ * and the real component manager is a public API, make sure to forward the public methods
+ * to the implementation.
+ *
+ */
+template <typename ... Elements>
+class UTILS_PUBLIC SingleInstanceComponentManager {
+private:
+
+    // this is just to avoid using std::default_random_engine, since we're in a public header.
+    class default_random_engine {
+        uint32_t mState = 1u; // must be 0 < seed < 0x7fffffff
+    public:
+        inline uint32_t operator()() noexcept {
+            return mState = uint32_t((uint64_t(mState) * 48271u) % 0x7fffffffu);
+        }
+    };
+
+protected:
+    static constexpr size_t ENTITY_INDEX = sizeof ... (Elements);
+
+
+public:
+    using SoA = StructureOfArrays<Elements ..., Entity>;
+
+    using Structure = typename SoA::Structure;
+
+    using Instance = EntityInstanceBase::Type;
+
+    SingleInstanceComponentManager() noexcept {
+        // We always start with a dummy entry because index=0 is reserved. The component
+        // at index = 0, is guaranteed to be default-initialized.
+        // Sub-classes can use this to their advantage.
+        mData.push_back(Structure{});
+    }
+
+    SingleInstanceComponentManager(SingleInstanceComponentManager&&) noexcept {/* = default */}
+    SingleInstanceComponentManager& operator=(SingleInstanceComponentManager&&) noexcept {/* = default */}
+    ~SingleInstanceComponentManager() noexcept = default;
+
+    // not copyable
+    SingleInstanceComponentManager(SingleInstanceComponentManager const& rhs) = delete;
+    SingleInstanceComponentManager& operator=(SingleInstanceComponentManager const& rhs) = delete;
+
+
+    // returns true if the given Entity has a component of this Manager
+    bool hasComponent(Entity e) const noexcept {
+        return getInstance(e) != 0;
+    }
+
+    // Get instance of this Entity to be used to retrieve components
+    UTILS_NOINLINE
+    Instance getInstance(Entity e) const noexcept {
+        auto const& map = mInstanceMap;
+        // find() generates quite a bit of code
+        auto pos = map.find(e);
+        return pos != map.end() ? pos->second : 0;
+    }
+
+    // returns the number of components (i.e. size of each arrays)
+    size_t getComponentCount() const noexcept {
+        // The array as an extra dummy component at index 0, so the visible count is 1 less.
+        return mData.size() - 1;
+    }
+
+    bool empty() const noexcept {
+        return getComponentCount() == 0;
+    }
+
+    // returns a pointer to the Entity array. This is basically the list
+    // of entities this component manager handles.
+    // The pointer becomes invalid when adding or removing a component.
+    Entity const* getEntities() const noexcept {
+        return begin<ENTITY_INDEX>();
+    }
+
+    Entity getEntity(Instance i) const noexcept {
+        return elementAt<ENTITY_INDEX>(i);
+    }
+
+    // Add a component to the given Entity. If the entity already has a component from this
+    // manager, this function is a no-op.
+    // This invalidates all pointers components.
+    inline Instance addComponent(Entity e);
+
+    // Removes a component from the given entity.
+    // This invalidates all pointers components.
+    inline Instance removeComponent(Entity e);
+
+    // trigger one round of garbage collection. this is intended to be called on a regular
+    // basis. This gc gives up after it cannot randomly free 'ratio' component in a row.
+    void gc(const EntityManager& em, size_t ratio = 4) noexcept {
+        gc(em, ratio, [this](Entity e) {
+                    removeComponent(e);
+                });
+    }
+
+    // return the first instance
+    Instance begin() const noexcept { return 1u; }
+
+    // return the past-the-last instance
+    Instance end() const noexcept { return Instance(begin() + getComponentCount()); }
+
+    // return a pointer to the first element of the ElementIndex'th array
+    template<size_t ElementIndex>
+    typename SoA::template TypeAt<ElementIndex>* begin() noexcept {
+        return mData.template data<ElementIndex>() + 1;
+    }
+
+    template<size_t ElementIndex>
+    typename SoA::template TypeAt<ElementIndex> const* begin() const noexcept {
+        return mData.template data<ElementIndex>() + 1;
+    }
+
+    // return a pointer to the past-the-end element of the ElementIndex'th array
+    template<size_t ElementIndex>
+    typename SoA::template TypeAt<ElementIndex>* end() noexcept {
+        return begin<ElementIndex>() + getComponentCount();
+    }
+
+    template<size_t ElementIndex>
+    typename SoA::template TypeAt<ElementIndex> const* end() const noexcept {
+        return begin<ElementIndex>() + getComponentCount();
+    }
+
+    // return a Slice<>
+    template<size_t ElementIndex>
+    Slice<typename SoA::template TypeAt<ElementIndex>> slice() noexcept {
+        return { begin<ElementIndex>(), end<ElementIndex>() };
+    }
+
+    template<size_t ElementIndex>
+    Slice<const typename SoA::template TypeAt<ElementIndex>> slice() const noexcept {
+        return { begin<ElementIndex>(), end<ElementIndex>() };
+    }
+
+    // return a reference to the index'th element of the ElementIndex'th array
+    template<size_t ElementIndex>
+    typename SoA::template TypeAt<ElementIndex>& elementAt(Instance index) noexcept {
+        assert(index);
+        return data<ElementIndex>()[index];
+    }
+
+    template<size_t ElementIndex>
+    typename SoA::template TypeAt<ElementIndex> const& elementAt(Instance index) const noexcept {
+        assert(index);
+        return data<ElementIndex>()[index];
+    }
+
+    // returns a pointer to the RAW ARRAY of components including the first dummy component
+    // Use with caution.
+    template<size_t ElementIndex>
+    typename SoA::template TypeAt<ElementIndex> const* raw_array() const noexcept {
+        return data<ElementIndex>();
+    }
+
+    // We need our own version of Field because mData is private
+    template<size_t E>
+    struct Field : public SoA::template Field<E> {
+        Field(SingleInstanceComponentManager& soa, EntityInstanceBase::Type i) noexcept
+                : SoA::template Field<E>{ soa.mData, i } {
+        }
+        using SoA::template Field<E>::operator =;
+    };
+
+protected:
+    template<size_t ElementIndex>
+    typename SoA::template TypeAt<ElementIndex>* data() noexcept {
+        return mData.template data<ElementIndex>();
+    }
+
+    template<size_t ElementIndex>
+    typename SoA::template TypeAt<ElementIndex> const* data() const noexcept {
+        return mData.template data<ElementIndex>();
+    }
+
+    // swap only internals
+    void swap(Instance i, Instance j) noexcept {
+        assert(i);
+        assert(j);
+        if (i && j) {
+            // update the index map
+            auto& map = mInstanceMap;
+            Entity& ei = elementAt<ENTITY_INDEX>(i);
+            Entity& ej = elementAt<ENTITY_INDEX>(j);
+            std::swap(ei, ej);
+            if (ei) {
+                map[ei] = i;
+            }
+            if (ej) {
+                map[ej] = j;
+            }
+        }
+    }
+
+    template<typename REMOVE>
+    void gc(const EntityManager& em, size_t ratio,
+            REMOVE removeComponent) noexcept {
+        Entity const* entities = getEntities();
+        size_t count = getComponentCount();
+        size_t aliveInARow = 0;
+        default_random_engine& rng = mRng;
+        UTILS_NOUNROLL
+        while (count && aliveInARow < ratio) {
+            // note: using the modulo favorizes lower number
+            size_t i = rng() % count;
+            if (UTILS_LIKELY(em.isAlive(entities[i]))) {
+                ++aliveInARow;
+                continue;
+            }
+            aliveInARow = 0;
+            count--;
+            removeComponent(entities[i]);
+        }
+    }
+
+protected:
+    SoA mData;
+
+private:
+    // maps an entity to an instance index
+    tsl::robin_map<Entity, Instance, Entity::Hasher> mInstanceMap;
+    default_random_engine mRng;
+};
+
+// Keep these outside of the class because CLion has trouble parsing them
+template<typename ... Elements>
+typename SingleInstanceComponentManager<Elements ...>::Instance
+SingleInstanceComponentManager<Elements ...>::addComponent(Entity e) {
+    Instance ci = 0;
+    if (!e.isNull()) {
+        if (!hasComponent(e)) {
+            // this is like a push_back(e);
+            mData.push_back(Structure{}).template back<ENTITY_INDEX>() = e;
+            // index 0 is used when the component doesn't exist
+            ci = Instance(mData.size() - 1);
+            mInstanceMap[e] = ci;
+        } else {
+            // if the entity already has this component, just return its instance
+            ci = mInstanceMap[e];
+        }
+    }
+    assert(ci != 0);
+    return ci;
+}
+
+// Keep these outside of the class because CLion has trouble parsing them
+template <typename ... Elements>
+typename SingleInstanceComponentManager<Elements ...>::Instance
+SingleInstanceComponentManager<Elements ... >::removeComponent(Entity e) {
+    auto& map = mInstanceMap;
+    auto pos = map.find(e);
+    if (UTILS_LIKELY(pos != map.end())) {
+        size_t index = pos->second;
+        assert(index != 0);
+        size_t last = mData.size() - 1;
+        if (last != index) {
+            // move the last item to where we removed this component, as to keep
+            // the array tightly packed.
+            mData.forEach([index, last](auto* p) {
+                p[index] = std::move(p[last]);
+            });
+
+            Entity lastEntity = mData.template elementAt<ENTITY_INDEX>(index);
+            map[lastEntity] = index;
+        }
+        mData.pop_back();
+        map.erase(pos);
+        return last;
+    }
+    return 0;
+}
+
+
+} // namespace filament
+
+#endif // TNT_UTILS_SINGLEINSTANCECOMPONENTMANAGER_H

flutter_filament/windows/include/filament/utils/Slice.h

@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_SLICE_H
+#define TNT_UTILS_SLICE_H
+
+#include <utils/compiler.h>
+
+#include <utility>
+
+#include <assert.h>
+#include <stddef.h>
+
+namespace utils {
+
+/*
+ * A fixed-size slice of a container
+ */
+template <typename T>
+class Slice {
+public:
+    using iterator = T*;
+    using const_iterator = T const*;
+    using value_type = T;
+    using reference = T&;
+    using const_reference = T const&;
+    using pointer = T*;
+    using const_pointer = T const*;
+    using size_type = size_t;
+
+    Slice() noexcept = default;
+
+    Slice(const_iterator begin, const_iterator end) noexcept
+            : mBegin(const_cast<iterator>(begin)),
+              mEnd(const_cast<iterator>(end)) {
+    }
+
+    Slice(const_pointer begin, size_type count) noexcept
+            : mBegin(const_cast<iterator>(begin)),
+              mEnd(mBegin + count) {
+    }
+
+    Slice(Slice const& rhs) noexcept = default;
+    Slice(Slice&& rhs) noexcept = default;
+    Slice& operator=(Slice const& rhs) noexcept = default;
+    Slice& operator=(Slice&& rhs) noexcept = default;
+
+    void set(pointer begin, size_type count) UTILS_RESTRICT noexcept {
+        mBegin = begin;
+        mEnd = begin + count;
+    }
+
+    void set(iterator begin, iterator end) UTILS_RESTRICT noexcept {
+        mBegin = begin;
+        mEnd = end;
+    }
+
+    void swap(Slice& rhs) UTILS_RESTRICT noexcept {
+        std::swap(mBegin, rhs.mBegin);
+        std::swap(mEnd, rhs.mEnd);
+    }
+
+    void clear() UTILS_RESTRICT noexcept {
+        mBegin = nullptr;
+        mEnd = nullptr;
+    }
+
+    // size
+    size_t size() const UTILS_RESTRICT noexcept { return mEnd - mBegin; }
+    size_t sizeInBytes() const UTILS_RESTRICT noexcept { return size() * sizeof(T); }
+    bool empty() const UTILS_RESTRICT noexcept { return size() == 0; }
+
+    // iterators
+    iterator begin() UTILS_RESTRICT noexcept { return mBegin; }
+    const_iterator begin() const UTILS_RESTRICT noexcept { return mBegin; }
+    const_iterator cbegin() const UTILS_RESTRICT noexcept { return this->begin(); }
+    iterator end() UTILS_RESTRICT noexcept { return mEnd; }
+    const_iterator end() const UTILS_RESTRICT noexcept { return mEnd; }
+    const_iterator cend() const UTILS_RESTRICT noexcept { return this->end(); }
+
+    // data access
+    reference operator[](size_t n) UTILS_RESTRICT noexcept {
+        assert(n < size());
+        return mBegin[n];
+    }
+
+    const_reference operator[](size_t n) const UTILS_RESTRICT noexcept {
+        assert(n < size());
+        return mBegin[n];
+    }
+
+    reference at(size_t n) UTILS_RESTRICT noexcept {
+        return operator[](n);
+    }
+
+    const_reference at(size_t n) const UTILS_RESTRICT noexcept {
+        return operator[](n);
+    }
+
+    reference front() UTILS_RESTRICT noexcept {
+        assert(!empty());
+        return *mBegin;
+    }
+
+    const_reference front() const UTILS_RESTRICT noexcept {
+        assert(!empty());
+        return *mBegin;
+    }
+
+    reference back() UTILS_RESTRICT noexcept {
+        assert(!empty());
+        return *(this->end() - 1);
+    }
+
+    const_reference back() const UTILS_RESTRICT noexcept {
+        assert(!empty());
+        return *(this->end() - 1);
+    }
+
+    pointer data() UTILS_RESTRICT noexcept {
+        return this->begin();
+    }
+
+    const_pointer data() const UTILS_RESTRICT noexcept {
+        return this->begin();
+    }
+
+protected:
+    iterator mBegin = nullptr;
+    iterator mEnd = nullptr;
+};
+
+} // namespace utils
+
+#endif // TNT_UTILS_SLICE_H

flutter_filament/windows/include/filament/utils/SpinLock.h

@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_SPINLOCK_H
+#define TNT_UTILS_SPINLOCK_H
+
+#include <utils/compiler.h>
+
+#include <utils/Mutex.h>
+
+#include <atomic>
+#include <type_traits>
+
+#include <assert.h>
+#include <stddef.h>
+
+namespace utils {
+namespace details {
+
+class SpinLock {
+    std::atomic_flag mLock = ATOMIC_FLAG_INIT;
+
+public:
+    void lock() noexcept {
+        UTILS_PREFETCHW(&mLock);
+#ifdef __ARM_ACLE
+        // we signal an event on this CPU, so that the first yield() will be a no-op,
+        // and falls through the test_and_set(). This is more efficient than a while { }
+        // construct.
+        UTILS_SIGNAL_EVENT();
+        do {
+            yield();
+        } while (mLock.test_and_set(std::memory_order_acquire));
+#else
+        goto start;
+        do {
+            yield();
+start: ;
+        } while (mLock.test_and_set(std::memory_order_acquire));
+#endif
+    }
+
+    void unlock() noexcept {
+        mLock.clear(std::memory_order_release);
+#ifdef __ARM_ARCH_7A__
+        // on ARMv7a SEL is needed
+        UTILS_SIGNAL_EVENT();
+        // as well as a memory barrier is needed
+        __dsb(0xA);     // ISHST = 0xA (b1010)
+#else
+        // on ARMv8 we could avoid the call to SE, but we'd need to write the
+        // test_and_set() above by hand, so the WFE only happens without a STRX first.
+        UTILS_BROADCAST_EVENT();
+#endif
+    }
+
+private:
+    inline void yield() noexcept {
+        // on x86 call pause instruction, on ARM call WFE
+        UTILS_WAIT_FOR_EVENT();
+    }
+};
+} // namespace details
+
+#if UTILS_HAS_SANITIZE_THREAD
+// Active spins with atomics slow down execution too much under ThreadSanitizer.
+using SpinLock = Mutex;
+#elif defined(__ARM_ARCH_7A__)
+// We've had problems with  "wfe" on some ARM-V7 devices, causing spurious SIGILL
+using SpinLock = Mutex;
+#else
+using SpinLock = details::SpinLock;
+#endif
+
+} // namespace utils
+
+#endif // TNT_UTILS_SPINLOCK_H

flutter_filament/windows/include/filament/utils/StructureOfArrays.h

@@ -0,0 +1,691 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_STRUCTUREOFARRAYS_H
+#define TNT_UTILS_STRUCTUREOFARRAYS_H
+
+#include <utils/Allocator.h>
+#include <utils/compiler.h>
+#include <utils/Slice.h>
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <algorithm>
+#include <array>        // note: this is safe, see how std::array is used below (inline / private)
+#include <cstddef>
+#include <iterator>     // for std::random_access_iterator_tag
+#include <tuple>
+#include <utility>
+
+namespace utils {
+
+template <typename Allocator, typename ... Elements>
+class StructureOfArraysBase {
+    // number of elements
+    static constexpr const size_t kArrayCount = sizeof...(Elements);
+
+public:
+    using SoA = StructureOfArraysBase<Allocator, Elements...>;
+
+    using Structure = std::tuple<Elements...>;
+
+    // Type of the Nth array
+    template<size_t N>
+    using TypeAt = typename std::tuple_element_t<N, Structure>;
+
+    // Number of arrays
+    static constexpr size_t getArrayCount() noexcept { return kArrayCount; }
+
+    // Size needed to store "size" array elements
+    static size_t getNeededSize(size_t size) noexcept {
+        return getOffset(kArrayCount - 1, size) + sizeof(TypeAt<kArrayCount - 1>) * size;
+    }
+
+    // --------------------------------------------------------------------------------------------
+
+    class IteratorValue;
+    template<typename T> class Iterator;
+    using iterator = Iterator<StructureOfArraysBase*>;
+    using const_iterator = Iterator<StructureOfArraysBase const*>;
+    using size_type = size_t;
+    using difference_type = ptrdiff_t;
+
+    /*
+     * An object that represents a reference to the type dereferenced by iterator.
+     * In other words, it's the return type of iterator::operator*(), and since it
+     * cannot be a C++ reference (&), it's an object that acts like it.
+     */
+    class IteratorValueRef {
+        friend class IteratorValue;
+        friend iterator;
+        friend const_iterator;
+        StructureOfArraysBase* const UTILS_RESTRICT soa;
+        size_t const index;
+
+        IteratorValueRef(StructureOfArraysBase* soa, size_t index) : soa(soa), index(index) { }
+
+        // assigns a value_type to a reference (i.e. assigns to what's pointed to by the reference)
+        template<size_t ... Is>
+        IteratorValueRef& assign(IteratorValue const& rhs, std::index_sequence<Is...>);
+
+        // assigns a value_type to a reference (i.e. assigns to what's pointed to by the reference)
+        template<size_t ... Is>
+        IteratorValueRef& assign(IteratorValue&& rhs, std::index_sequence<Is...>) noexcept;
+
+        // objects pointed to by reference can be swapped, so provide the special swap() function.
+        friend void swap(IteratorValueRef lhs, IteratorValueRef rhs) {
+            lhs.soa->swap(lhs.index, rhs.index);
+        }
+
+    public:
+        // references can be created by copy-assignment only
+        IteratorValueRef(IteratorValueRef const& rhs) noexcept : soa(rhs.soa), index(rhs.index) { }
+
+        // copy the content of a reference to the content of this one
+        IteratorValueRef& operator=(IteratorValueRef const& rhs);
+
+        // move the content of a reference to the content of this one
+        IteratorValueRef& operator=(IteratorValueRef&& rhs) noexcept;
+
+        // copy a value_type to the content of this reference
+        IteratorValueRef& operator=(IteratorValue const& rhs) {
+            return assign(rhs, std::make_index_sequence<kArrayCount>());
+        }
+
+        // move a value_type to the content of this reference
+        IteratorValueRef& operator=(IteratorValue&& rhs) noexcept {
+            return assign(rhs, std::make_index_sequence<kArrayCount>());
+        }
+
+        // access the elements of this reference (i.e. the "fields" of the structure)
+        template<size_t I> TypeAt<I> const& get() const { return soa->elementAt<I>(index); }
+        template<size_t I> TypeAt<I>& get() { return soa->elementAt<I>(index); }
+    };
+
+
+    /*
+     * The value_type of iterator. This is basically the "structure" of the SoA.
+     * Internally we're using a tuple<> to store the data.
+     * This object is not trivial to construct, as it copies an entry of the SoA.
+     */
+    class IteratorValue {
+        friend class IteratorValueRef;
+        friend iterator;
+        friend const_iterator;
+        using Type = std::tuple<typename std::decay<Elements>::type...>;
+        Type elements;
+
+        template<size_t ... Is>
+        static Type init(IteratorValueRef const& rhs, std::index_sequence<Is...>) {
+            return Type{ rhs.soa->template elementAt<Is>(rhs.index)... };
+        }
+
+        template<size_t ... Is>
+        static Type init(IteratorValueRef&& rhs, std::index_sequence<Is...>) noexcept {
+            return Type{ std::move(rhs.soa->template elementAt<Is>(rhs.index))... };
+        }
+
+    public:
+        IteratorValue(IteratorValue const& rhs) = default;
+        IteratorValue(IteratorValue&& rhs) noexcept = default;
+        IteratorValue& operator=(IteratorValue const& rhs) = default;
+        IteratorValue& operator=(IteratorValue&& rhs) noexcept = default;
+
+        // initialize and assign from a StructureRef
+        IteratorValue(IteratorValueRef const& rhs)
+                : elements(init(rhs, std::make_index_sequence<kArrayCount>())) {}
+        IteratorValue(IteratorValueRef&& rhs) noexcept
+                : elements(init(rhs, std::make_index_sequence<kArrayCount>())) {}
+        IteratorValue& operator=(IteratorValueRef const& rhs) { return operator=(IteratorValue(rhs)); }
+        IteratorValue& operator=(IteratorValueRef&& rhs) noexcept { return operator=(IteratorValue(rhs)); }
+
+        // access the elements of this value_Type (i.e. the "fields" of the structure)
+        template<size_t I> TypeAt<I> const& get() const { return std::get<I>(elements); }
+        template<size_t I> TypeAt<I>& get() { return std::get<I>(elements); }
+    };
+
+
+    /*
+     * An iterator to the SoA. This is only intended to be used with STL's algorithm, e.g.: sort().
+     * Normally, SoA is not iterated globally, but rather an array at a time.
+     * Iterating itself is not too costly, as well as dereferencing by reference. However,
+     * dereferencing by value is.
+     */
+    template<typename CVQualifiedSOAPointer>
+    class Iterator {
+        friend class StructureOfArraysBase;
+        CVQualifiedSOAPointer soa; // don't use restrict, can have aliases if multiple iterators are created
+        size_t index;
+
+        Iterator(CVQualifiedSOAPointer soa, size_t index) : soa(soa), index(index) {}
+
+    public:
+        using value_type = IteratorValue;
+        using reference = IteratorValueRef;
+        using pointer = IteratorValueRef*;    // FIXME: this should be a StructurePtr type
+        using difference_type = ptrdiff_t;
+        using iterator_category = std::random_access_iterator_tag;
+
+        Iterator(Iterator const& rhs) noexcept = default;
+        Iterator& operator=(Iterator const& rhs) = default;
+
+        reference operator*() const { return { soa, index }; }
+        reference operator*() { return { soa, index }; }
+        reference operator[](size_t n) { return *(*this + n); }
+
+        template<size_t I> TypeAt<I> const& get() const { return soa->template elementAt<I>(index); }
+        template<size_t I> TypeAt<I>& get() { return soa->template elementAt<I>(index); }
+
+        Iterator& operator++() { ++index; return *this; }
+        Iterator& operator--() { --index; return *this; }
+        Iterator& operator+=(size_t n) { index += n; return *this; }
+        Iterator& operator-=(size_t n) { index -= n; return *this; }
+        Iterator operator+(size_t n) const { return { soa, index + n }; }
+        Iterator operator-(size_t n) const { return { soa, index - n }; }
+        difference_type operator-(Iterator const& rhs) const { return index - rhs.index; }
+        bool operator==(Iterator const& rhs) const { return (index == rhs.index); }
+        bool operator!=(Iterator const& rhs) const { return (index != rhs.index); }
+        bool operator>=(Iterator const& rhs) const { return (index >= rhs.index); }
+        bool operator> (Iterator const& rhs) const { return (index >  rhs.index); }
+        bool operator<=(Iterator const& rhs) const { return (index <= rhs.index); }
+        bool operator< (Iterator const& rhs) const { return (index <  rhs.index); }
+
+        // Postfix operator needed by Microsoft STL.
+        const Iterator operator++(int) { Iterator it(*this); index++; return it; }
+        const Iterator operator--(int) { Iterator it(*this); index--; return it; }
+    };
+
+    iterator begin() noexcept { return { this, 0u }; }
+    iterator end() noexcept { return { this, mSize }; }
+    const_iterator begin() const noexcept { return { this, 0u }; }
+    const_iterator end() const noexcept { return { this, mSize }; }
+
+    // --------------------------------------------------------------------------------------------
+
+    StructureOfArraysBase() = default;
+
+    explicit StructureOfArraysBase(size_t capacity) {
+        setCapacity(capacity);
+    }
+
+    // not copyable for now
+    StructureOfArraysBase(StructureOfArraysBase const& rhs) = delete;
+    StructureOfArraysBase& operator=(StructureOfArraysBase const& rhs) = delete;
+
+    // movability is trivial, so support it
+    StructureOfArraysBase(StructureOfArraysBase&& rhs) noexcept {
+        using std::swap;
+        swap(mCapacity, rhs.mCapacity);
+        swap(mSize, rhs.mSize);
+        swap(mArrays, rhs.mArrays);
+        swap(mAllocator, rhs.mAllocator);
+    }
+
+    StructureOfArraysBase& operator=(StructureOfArraysBase&& rhs) noexcept {
+        if (this != &rhs) {
+            using std::swap;
+            swap(mCapacity, rhs.mCapacity);
+            swap(mSize, rhs.mSize);
+            swap(mArrays, rhs.mArrays);
+            swap(mAllocator, rhs.mAllocator);
+        }
+        return *this;
+    }
+
+    ~StructureOfArraysBase() {
+        destroy_each(0, mSize);
+        mAllocator.free(std::get<0>(mArrays));
+    }
+
+    // --------------------------------------------------------------------------------------------
+
+    // return the size the array
+    size_t size() const noexcept {
+        return mSize;
+    }
+
+    // return the capacity of the array
+    size_t capacity() const noexcept {
+        return mCapacity;
+    }
+
+    // set the capacity of the array. the capacity cannot be smaller than the current size,
+    // the call is a no-op in that case.
+    UTILS_NOINLINE
+    void setCapacity(size_t capacity) {
+        // allocate enough space for "capacity" elements of each array
+        // capacity cannot change when optional storage is specified
+        if (capacity >= mSize) {
+            // TODO: not entirely sure if "max" of all alignments is always correct
+            constexpr size_t align = std::max({ std::max(alignof(std::max_align_t), alignof(Elements))... });
+            const size_t sizeNeeded = getNeededSize(capacity);
+            void* buffer = mAllocator.alloc(sizeNeeded, align);
+            auto const oldBuffer = std::get<0>(mArrays);
+
+            // move all the items (one array at a time) from the old allocation to the new
+            // this also update the array pointers
+            move_each(buffer, capacity);
+
+            // free the old buffer
+            mAllocator.free(oldBuffer);
+
+            // and make sure to update the capacity
+            mCapacity = capacity;
+        }
+    }
+
+    void ensureCapacity(size_t needed) {
+        if (UTILS_UNLIKELY(needed > mCapacity)) {
+            // not enough space, increase the capacity
+            const size_t capacity = (needed * 3 + 1) / 2;
+            setCapacity(capacity);
+        }
+    }
+
+    // grow or shrink the array to the given size. When growing, new elements are constructed
+    // with their default constructor. when shrinking, discarded elements are destroyed.
+    // If the arrays don't have enough capacity, the capacity is increased accordingly
+    // (the capacity is set to 3/2 of the asked size).
+    UTILS_NOINLINE
+    void resize(size_t needed) {
+        ensureCapacity(needed);
+        resizeNoCheck(needed);
+        if (needed <= mCapacity) {
+            // TODO: see if we should shrink the arrays
+        }
+    }
+
+    void clear() noexcept {
+        resizeNoCheck(0);
+    }
+
+
+    inline void swap(size_t i, size_t j) noexcept {
+        forEach([i, j](auto p) {
+            using std::swap;
+            swap(p[i], p[j]);
+        });
+    }
+
+    // remove and destroy the last element of each array
+    inline void pop_back() noexcept {
+        if (mSize) {
+            destroy_each(mSize - 1, mSize);
+            mSize--;
+        }
+    }
+
+    // create an element at the end of each array
+    StructureOfArraysBase& push_back() noexcept {
+        resize(mSize + 1);
+        return *this;
+    }
+
+    StructureOfArraysBase& push_back(Structure&& args) noexcept {
+        ensureCapacity(mSize + 1);
+        return push_back_unsafe(std::forward<Structure>(args));
+    }
+
+    StructureOfArraysBase& push_back(Elements const& ... args) noexcept {
+        ensureCapacity(mSize + 1);
+        return push_back_unsafe(args...);
+    }
+
+    StructureOfArraysBase& push_back(Elements&& ... args) noexcept {
+        ensureCapacity(mSize + 1);
+        return push_back_unsafe(std::forward<Elements>(args)...);
+    }
+
+    // in C++20 we could use a lambda with explicit template parameter instead
+    struct PushBackUnsafeClosure {
+        size_t last;
+        std::tuple<Elements...> args;
+        inline explicit PushBackUnsafeClosure(size_t last, Structure&& args)
+                : last(last), args(std::forward<Structure>(args)) {}
+        template<size_t I>
+        inline void operator()(TypeAt<I>* p) {
+            new(p + last) TypeAt<I>{ std::get<I>(args) };
+        }
+    };
+
+    StructureOfArraysBase& push_back_unsafe(Structure&& args) noexcept {
+        for_each_index(mArrays,
+                PushBackUnsafeClosure{ mSize++, std::forward<Structure>(args) });
+        return *this;
+    }
+
+    StructureOfArraysBase& push_back_unsafe(Elements const& ... args) noexcept {
+        for_each_index(mArrays,
+                PushBackUnsafeClosure{ mSize++, { args... } });
+        return *this;
+    }
+
+    StructureOfArraysBase& push_back_unsafe(Elements&& ... args) noexcept {
+        for_each_index(mArrays,
+                PushBackUnsafeClosure{ mSize++, { std::forward<Elements>(args)... }});
+        return *this;
+    }
+
+    template<typename F, typename ... ARGS>
+    void forEach(F&& f, ARGS&& ... args) {
+        for_each(mArrays, [&](size_t, auto* p) {
+            f(p, std::forward<ARGS>(args)...);
+        });
+    }
+
+    // return a pointer to the first element of the ElementIndex]th array
+    template<size_t ElementIndex>
+    TypeAt<ElementIndex>* data() noexcept {
+        return std::get<ElementIndex>(mArrays);
+    }
+
+    template<size_t ElementIndex>
+    TypeAt<ElementIndex> const* data() const noexcept {
+        return std::get<ElementIndex>(mArrays);
+    }
+
+    template<size_t ElementIndex>
+    TypeAt<ElementIndex>* begin() noexcept {
+        return std::get<ElementIndex>(mArrays);
+    }
+
+    template<size_t ElementIndex>
+    TypeAt<ElementIndex> const* begin() const noexcept {
+        return std::get<ElementIndex>(mArrays);
+    }
+
+    template<size_t ElementIndex>
+    TypeAt<ElementIndex>* end() noexcept {
+        return std::get<ElementIndex>(mArrays) + size();
+    }
+
+    template<size_t ElementIndex>
+    TypeAt<ElementIndex> const* end() const noexcept {
+        return std::get<ElementIndex>(mArrays) + size();
+    }
+
+    template<size_t ElementIndex>
+    Slice<TypeAt<ElementIndex>> slice() noexcept {
+        return { begin<ElementIndex>(), end<ElementIndex>() };
+    }
+
+    template<size_t ElementIndex>
+    Slice<const TypeAt<ElementIndex>> slice() const noexcept {
+        return { begin<ElementIndex>(), end<ElementIndex>() };
+    }
+
+    // return a reference to the index'th element of the ElementIndex'th array
+    template<size_t ElementIndex>
+    TypeAt<ElementIndex>& elementAt(size_t index) noexcept {
+        return data<ElementIndex>()[index];
+    }
+
+    template<size_t ElementIndex>
+    TypeAt<ElementIndex> const& elementAt(size_t index) const noexcept {
+        return data<ElementIndex>()[index];
+    }
+
+    // return a reference to the last element of the ElementIndex'th array
+    template<size_t ElementIndex>
+    TypeAt<ElementIndex>& back() noexcept {
+        return data<ElementIndex>()[size() - 1];
+    }
+
+    template<size_t ElementIndex>
+    TypeAt<ElementIndex> const& back() const noexcept {
+        return data<ElementIndex>()[size() - 1];
+    }
+
+    template <size_t E, typename IndexType = uint32_t>
+    struct Field {
+        SoA& soa;
+        IndexType i;
+        using Type = typename SoA::template TypeAt<E>;
+
+        UTILS_ALWAYS_INLINE Field& operator = (Field&& rhs) noexcept {
+            soa.elementAt<E>(i) = soa.elementAt<E>(rhs.i);
+            return *this;
+        }
+
+        // auto-conversion to the field's type
+        UTILS_ALWAYS_INLINE operator Type&() noexcept {
+            return soa.elementAt<E>(i);
+        }
+        UTILS_ALWAYS_INLINE operator Type const&() const noexcept {
+            return soa.elementAt<E>(i);
+        }
+        // dereferencing the selected field
+        UTILS_ALWAYS_INLINE Type& operator ->() noexcept {
+            return soa.elementAt<E>(i);
+        }
+        UTILS_ALWAYS_INLINE Type const& operator ->() const noexcept {
+            return soa.elementAt<E>(i);
+        }
+        // address-of the selected field
+        UTILS_ALWAYS_INLINE Type* operator &() noexcept {
+            return &soa.elementAt<E>(i);
+        }
+        UTILS_ALWAYS_INLINE Type const* operator &() const noexcept {
+            return &soa.elementAt<E>(i);
+        }
+        // assignment to the field
+        UTILS_ALWAYS_INLINE Type const& operator = (Type const& other) noexcept {
+            return (soa.elementAt<E>(i) = other);
+        }
+        UTILS_ALWAYS_INLINE Type const& operator = (Type&& other) noexcept {
+            return (soa.elementAt<E>(i) = other);
+        }
+        // comparisons
+        UTILS_ALWAYS_INLINE bool operator==(Type const& other) const {
+            return (soa.elementAt<E>(i) == other);
+        }
+        UTILS_ALWAYS_INLINE bool operator!=(Type const& other) const {
+            return (soa.elementAt<E>(i) != other);
+        }
+        // calling the field
+        template <typename ... ARGS>
+        UTILS_ALWAYS_INLINE decltype(auto) operator()(ARGS&& ... args) noexcept {
+            return soa.elementAt<E>(i)(std::forward<ARGS>(args)...);
+        }
+        template <typename ... ARGS>
+        UTILS_ALWAYS_INLINE decltype(auto) operator()(ARGS&& ... args) const noexcept {
+            return soa.elementAt<E>(i)(std::forward<ARGS>(args)...);
+        }
+    };
+
+private:
+    template<std::size_t I = 0, typename FuncT, typename... Tp>
+    inline typename std::enable_if<I == sizeof...(Tp), void>::type
+    for_each(std::tuple<Tp...>&, FuncT) {}
+
+    template<std::size_t I = 0, typename FuncT, typename... Tp>
+    inline typename std::enable_if<I < sizeof...(Tp), void>::type
+    for_each(std::tuple<Tp...>& t, FuncT f) {
+        f(I, std::get<I>(t));
+        for_each<I + 1, FuncT, Tp...>(t, f);
+    }
+
+    template<std::size_t I = 0, typename FuncT, typename... Tp>
+    inline typename std::enable_if<I == sizeof...(Tp), void>::type
+    for_each_index(std::tuple<Tp...>&, FuncT) {}
+
+    template<std::size_t I = 0, typename FuncT, typename... Tp>
+    inline typename std::enable_if<I < sizeof...(Tp), void>::type
+    for_each_index(std::tuple<Tp...>& t, FuncT f) {
+        f.template operator()<I>(std::get<I>(t));
+        for_each_index<I + 1, FuncT, Tp...>(t, f);
+    }
+
+    inline void resizeNoCheck(size_t needed) noexcept {
+        assert(mCapacity >= needed);
+        if (needed < mSize) {
+            // we shrink the arrays
+            destroy_each(needed, mSize);
+        } else if (needed > mSize) {
+            // we grow the arrays
+            construct_each(mSize, needed);
+        }
+        // record the new size of the arrays
+        mSize = needed;
+    }
+
+    // this calculates the offset adjusted for all data alignment of a given array
+    static inline size_t getOffset(size_t index, size_t capacity) noexcept {
+        auto offsets = getOffsets(capacity);
+        return offsets[index];
+    }
+
+    static inline std::array<size_t, kArrayCount> getOffsets(size_t capacity) noexcept {
+        // compute the required size of each array
+        const size_t sizes[] = { (sizeof(Elements) * capacity)... };
+
+        // we align each array to at least the same alignment guaranteed by malloc
+        constexpr size_t const alignments[] = { std::max(alignof(std::max_align_t), alignof(Elements))... };
+
+        // hopefully most of this gets unrolled and inlined
+        std::array<size_t, kArrayCount> offsets;
+        offsets[0] = 0;
+        UTILS_UNROLL
+        for (size_t i = 1; i < kArrayCount; i++) {
+            size_t unalignment = (offsets[i - 1] + sizes[i - 1]) % alignments[i];
+            size_t alignment = unalignment ? (alignments[i] - unalignment) : 0;
+            offsets[i] = offsets[i - 1] + (sizes[i - 1] + alignment);
+            assert_invariant(offsets[i] % alignments[i] == 0);
+        }
+        return offsets;
+    }
+
+    void construct_each(size_t from, size_t to) noexcept {
+        forEach([from, to](auto p) {
+            using T = typename std::decay<decltype(*p)>::type;
+            // note: scalar types like int/float get initialized to zero
+            if constexpr (!std::is_trivially_default_constructible_v<T>) {
+                for (size_t i = from; i < to; i++) {
+                    new(p + i) T();
+                }
+            }
+        });
+    }
+
+    void destroy_each(size_t from, size_t to) noexcept {
+        forEach([from, to](auto p) {
+            using T = typename std::decay<decltype(*p)>::type;
+            if constexpr (!std::is_trivially_destructible_v<T>) {
+                for (size_t i = from; i < to; i++) {
+                    p[i].~T();
+                }
+            }
+        });
+    }
+
+    void move_each(void* buffer, size_t capacity) noexcept {
+        auto offsets = getOffsets(capacity);
+        size_t index = 0;
+        if (mSize) {
+            auto size = mSize; // placate a compiler warning
+            forEach([buffer, &index, &offsets, size](auto p) {
+                using T = typename std::decay<decltype(*p)>::type;
+                T* UTILS_RESTRICT b = static_cast<T*>(buffer);
+
+                // go through each element and move them from the old array to the new
+                // then destroy them from the old array
+                T* UTILS_RESTRICT const arrayPointer =
+                        reinterpret_cast<T*>(uintptr_t(b) + offsets[index]);
+
+                // for trivial cases, just call memcpy()
+                if constexpr (std::is_trivially_copyable_v<T> &&
+                              std::is_trivially_destructible_v<T>) {
+                    memcpy(arrayPointer, p, size * sizeof(T));
+                } else {
+                    for (size_t i = 0; i < size; i++) {
+                        // we move an element by using the in-place move-constructor
+                        new(arrayPointer + i) T(std::move(p[i]));
+                        if constexpr (!std::is_trivially_destructible_v<T>) {
+                            // and delete them by calling the destructor directly
+                            p[i].~T();
+                        }
+                    }
+                }
+                index++;
+            });
+        }
+
+        // update the pointers
+        for_each(mArrays, [buffer, &offsets](size_t i, auto&& p) {
+            using Type = std::remove_reference_t<decltype(p)>;
+            p = Type((char*)buffer + offsets[i]);
+        });
+    }
+
+    // capacity in array elements
+    size_t mCapacity = 0;
+    // size in array elements
+    size_t mSize = 0;
+    // N pointers to each arrays
+    std::tuple<std::add_pointer_t<Elements>...> mArrays{};
+    Allocator mAllocator;
+};
+
+
+template<typename Allocator, typename... Elements>
+inline
+typename StructureOfArraysBase<Allocator, Elements...>::IteratorValueRef&
+StructureOfArraysBase<Allocator, Elements...>::IteratorValueRef::operator=(
+        StructureOfArraysBase::IteratorValueRef const& rhs) {
+    return operator=(IteratorValue(rhs));
+}
+
+template<typename Allocator, typename... Elements>
+inline
+typename StructureOfArraysBase<Allocator, Elements...>::IteratorValueRef&
+StructureOfArraysBase<Allocator, Elements...>::IteratorValueRef::operator=(
+        StructureOfArraysBase::IteratorValueRef&& rhs) noexcept {
+    return operator=(IteratorValue(rhs));
+}
+
+template<typename Allocator, typename... Elements>
+template<size_t... Is>
+inline
+typename StructureOfArraysBase<Allocator, Elements...>::IteratorValueRef&
+StructureOfArraysBase<Allocator, Elements...>::IteratorValueRef::assign(
+        StructureOfArraysBase::IteratorValue const& rhs, std::index_sequence<Is...>) {
+    // implements IteratorValueRef& IteratorValueRef::operator=(IteratorValue const& rhs)
+    auto UTILS_UNUSED l = { (soa->elementAt<Is>(index) = std::get<Is>(rhs.elements), 0)... };
+    return *this;
+}
+
+template<typename Allocator, typename... Elements>
+template<size_t... Is>
+inline
+typename StructureOfArraysBase<Allocator, Elements...>::IteratorValueRef&
+StructureOfArraysBase<Allocator, Elements...>::IteratorValueRef::assign(
+        StructureOfArraysBase::IteratorValue&& rhs, std::index_sequence<Is...>) noexcept {
+    // implements IteratorValueRef& IteratorValueRef::operator=(IteratorValue&& rhs) noexcept
+    auto UTILS_UNUSED l = {
+            (soa->elementAt<Is>(index) = std::move(std::get<Is>(rhs.elements)), 0)... };
+    return *this;
+}
+
+template <typename ... Elements>
+using StructureOfArrays = StructureOfArraysBase<HeapArena<>, Elements ...>;
+
+} // namespace utils
+
+#endif // TNT_UTILS_STRUCTUREOFARRAYS_H
+

flutter_filament/windows/include/filament/utils/algorithm.h

@@ -0,0 +1,214 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_ALGORITHM_H
+#define TNT_UTILS_ALGORITHM_H
+
+#include <utils/compiler.h>
+
+#include <type_traits>      // for std::enable_if
+
+#include <limits.h>
+#include <stdint.h>
+
+namespace utils {
+
+namespace details {
+
+template<typename T>
+constexpr inline T popcount(T v) noexcept {
+    static_assert(sizeof(T) * CHAR_BIT <= 128, "details::popcount() only support up to 128 bits");
+    constexpr T ONES = ~T(0);
+    v = v - ((v >> 1u) & ONES / 3);
+    v = (v & ONES / 15 * 3) + ((v >> 2u) & ONES / 15 * 3);
+    v = (v + (v >> 4u)) & ONES / 255 * 15;
+    return (T) (v * (ONES / 255)) >> (sizeof(T) - 1) * CHAR_BIT;
+}
+
+template<typename T, typename = std::enable_if_t<std::is_unsigned<T>::value>>
+constexpr inline T clz(T x) noexcept {
+    static_assert(sizeof(T) * CHAR_BIT <= 128, "details::clz() only support up to 128 bits");
+    x |= (x >> 1u);
+    x |= (x >> 2u);
+    x |= (x >> 4u);
+    x |= (x >> 8u);
+    x |= (x >> 16u);
+    if constexpr (sizeof(T) * CHAR_BIT >= 64) {   // just to silence compiler warning
+        x |= (x >> 32u);
+    }
+    if constexpr (sizeof(T) * CHAR_BIT >= 128) {   // just to silence compiler warning
+        x |= (x >> 64u);
+    }
+    return T(sizeof(T) * CHAR_BIT) - details::popcount(x);
+}
+
+template<typename T, typename = std::enable_if_t<std::is_unsigned<T>::value>>
+constexpr inline T ctz(T x) noexcept {
+    static_assert(sizeof(T) * CHAR_BIT <= 64, "details::ctz() only support up to 64 bits");
+    T c = sizeof(T) * CHAR_BIT;
+#if defined(_MSC_VER)
+    // equivalent to x & -x, but MSVC yield a warning for using unary minus operator on unsigned types
+    x &= (~x + 1);
+#else
+    // equivalent to x & (~x + 1), but some compilers generate a better sequence on ARM
+    x &= -x;
+#endif
+    if (x) c--;
+    if (sizeof(T) * CHAR_BIT >= 64) {
+        if (x & T(0x00000000FFFFFFFF)) c -= 32;
+    }
+    if (x & T(0x0000FFFF0000FFFF)) c -= 16;
+    if (x & T(0x00FF00FF00FF00FF)) c -= 8;
+    if (x & T(0x0F0F0F0F0F0F0F0F)) c -= 4;
+    if (x & T(0x3333333333333333)) c -= 2;
+    if (x & T(0x5555555555555555)) c -= 1;
+    return c;
+}
+
+} // namespace details
+
+constexpr inline UTILS_PUBLIC UTILS_PURE
+unsigned int UTILS_ALWAYS_INLINE clz(unsigned int x) noexcept {
+#if __has_builtin(__builtin_clz)
+    return __builtin_clz(x);
+#else
+    return details::clz(x);
+#endif
+}
+
+constexpr inline UTILS_PUBLIC UTILS_PURE
+unsigned long UTILS_ALWAYS_INLINE clz(unsigned long x) noexcept {
+#if __has_builtin(__builtin_clzl)
+    return __builtin_clzl(x);
+#else
+    return details::clz(x);
+#endif
+}
+
+constexpr inline UTILS_PUBLIC UTILS_PURE
+unsigned long long UTILS_ALWAYS_INLINE clz(unsigned long long x) noexcept {
+#if __has_builtin(__builtin_clzll)
+    return __builtin_clzll(x);
+#else
+    return details::clz(x);
+#endif
+}
+
+constexpr inline UTILS_PUBLIC UTILS_PURE
+unsigned int UTILS_ALWAYS_INLINE ctz(unsigned int x) noexcept {
+#if __has_builtin(__builtin_ctz)
+    return __builtin_ctz(x);
+#else
+    return details::ctz(x);
+#endif
+}
+
+constexpr inline UTILS_PUBLIC UTILS_PURE
+unsigned long UTILS_ALWAYS_INLINE ctz(unsigned long x) noexcept {
+#if __has_builtin(__builtin_ctzl)
+    return __builtin_ctzl(x);
+#else
+    return details::ctz(x);
+#endif
+}
+
+constexpr inline UTILS_PUBLIC UTILS_PURE
+unsigned long long UTILS_ALWAYS_INLINE ctz(unsigned long long x) noexcept {
+#if __has_builtin(__builtin_ctzll)
+    return __builtin_ctzll(x);
+#else
+    return details::ctz(x);
+#endif
+}
+
+constexpr inline UTILS_PUBLIC UTILS_PURE
+unsigned int UTILS_ALWAYS_INLINE popcount(unsigned int x) noexcept {
+#if __has_builtin(__builtin_popcount)
+    return __builtin_popcount(x);
+#else
+    return details::popcount(x);
+#endif
+}
+
+constexpr inline UTILS_PUBLIC UTILS_PURE
+unsigned long UTILS_ALWAYS_INLINE popcount(unsigned long x) noexcept {
+#if __has_builtin(__builtin_popcountl)
+    return __builtin_popcountl(x);
+#else
+    return details::popcount(x);
+#endif
+}
+
+constexpr inline UTILS_PUBLIC UTILS_PURE
+unsigned long long UTILS_ALWAYS_INLINE popcount(unsigned long long x) noexcept {
+#if __has_builtin(__builtin_popcountll)
+    return __builtin_popcountll(x);
+#else
+    return details::popcount(x);
+#endif
+}
+
+constexpr inline UTILS_PUBLIC UTILS_PURE
+uint8_t UTILS_ALWAYS_INLINE popcount(uint8_t x) noexcept {
+    return (uint8_t)popcount((unsigned int)x);
+}
+
+template<typename T,
+        typename = std::enable_if_t<std::is_integral<T>::value && std::is_unsigned<T>::value>>
+constexpr inline UTILS_PUBLIC UTILS_PURE
+T log2i(T x) noexcept {
+    return (sizeof(x) * 8 - 1u) - clz(x);
+}
+
+template<typename RandomAccessIterator, typename COMPARE>
+inline UTILS_PUBLIC
+RandomAccessIterator partition_point(
+        RandomAccessIterator first, RandomAccessIterator last, COMPARE pred,
+        bool assume_power_of_two = false) {
+    size_t len = last - first;
+
+    if (!assume_power_of_two) {
+        // handle non power-of-two sized arrays. If it's POT, the next line is a no-op
+        // and gets optimized out if the size is known at compile time.
+        len = 1u << (31 - clz(uint32_t(len)));     // next power of two length / 2
+        size_t difference = (last - first) - len;
+        first += !difference || pred(first[len]) ? difference : 0;
+    }
+
+    while (len) {
+        // The number of repetitions here doesn't affect the result. We manually unroll the loop
+        // twice, to guarantee we have at least two iterations without branches (for the case
+        // where the size is not known at compile time
+        first += pred(first[len>>=1u]) ? len : 0;
+        first += pred(first[len>>=1u]) ? len : 0;
+    }
+    first += pred(*first);
+    return first;
+}
+
+template <class To, class From>
+typename std::enable_if_t<
+    (sizeof(To) == sizeof(From)) &&
+    std::is_trivially_copyable<From>::value,
+    To>
+// constexpr support needs compiler magic
+bit_cast(const From &src) noexcept {
+    return reinterpret_cast<const To&>(src);
+}
+
+} // namespace utils
+
+#endif // TNT_UTILS_ALGORITHM_H

flutter_filament/windows/include/filament/utils/bitset.h

@@ -0,0 +1,330 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_BITSET_H
+#define TNT_UTILS_BITSET_H
+
+#include <utils/algorithm.h>
+#include <utils/compiler.h>
+#include <utils/debug.h>
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include <algorithm> // for std::fill
+#include <iterator>
+#include <type_traits>
+
+#if defined(__ARM_NEON)
+#   if defined(__ARM_ACLE) && defined(__aarch64__)
+#       include <arm_neon.h>
+#       define TNT_UTILS_BITSET_USE_NEON 1
+#   endif
+#endif
+
+namespace utils {
+
+/*
+ * This bitset<> class is different from std::bitset<> in that it allows us to control
+ * the exact storage size. This is useful for small bitset (e.g. < 64, on 64-bits machines).
+ * It also allows for lexicographical compares (i.e. sorting).
+ */
+
+template<typename T, size_t N = 1,
+        typename = typename std::enable_if<std::is_integral<T>::value &&
+                                           std::is_unsigned<T>::value>::type>
+class UTILS_PUBLIC bitset {
+    T storage[N];
+
+public:
+    static constexpr T BITS_PER_WORD = sizeof(T) * 8;
+    static constexpr T BIT_COUNT = BITS_PER_WORD * N;
+    static constexpr T WORLD_COUNT = N;
+    using container_type = T;
+
+    bitset() noexcept {
+        std::fill(std::begin(storage), std::end(storage), 0);
+    }
+
+    T getBitsAt(size_t n) const noexcept {
+        assert_invariant(n<N);
+        return storage[n];
+    }
+
+    T& getBitsAt(size_t n) noexcept {
+        assert_invariant(n<N);
+        return storage[n];
+    }
+
+    T getValue() const noexcept {
+        static_assert(N == 1, "bitfield must only have one storage word");
+        return storage[0];
+    }
+
+    void setValue(T value) noexcept {
+        static_assert(N == 1, "bitfield must only have one storage word");
+        storage[0] = value;
+    }
+
+    template<typename F>
+    void forEachSetBit(F exec) const noexcept {
+        for (size_t i = 0; i < N; i++) {
+            T v = storage[i];
+            while (v) {
+                T k = utils::ctz(v);
+                v &= ~(T(1) << k);
+                exec(size_t(k + BITS_PER_WORD * i));
+            }
+        }
+    }
+
+    size_t size() const noexcept { return N * BITS_PER_WORD; }
+
+    bool test(size_t bit) const noexcept { return operator[](bit); }
+
+    void set(size_t b) noexcept {
+        assert_invariant(b / BITS_PER_WORD < N);
+        storage[b / BITS_PER_WORD] |= T(1) << (b % BITS_PER_WORD);
+    }
+
+    void set(size_t b, bool value) noexcept {
+        assert_invariant(b / BITS_PER_WORD < N);
+        storage[b / BITS_PER_WORD] &= ~(T(1) << (b % BITS_PER_WORD));
+        storage[b / BITS_PER_WORD] |= T(value) << (b % BITS_PER_WORD);
+    }
+
+    void unset(size_t b) noexcept {
+        assert_invariant(b / BITS_PER_WORD < N);
+        storage[b / BITS_PER_WORD] &= ~(T(1) << (b % BITS_PER_WORD));
+    }
+
+    void flip(size_t b) noexcept {
+        assert_invariant(b / BITS_PER_WORD < N);
+        storage[b / BITS_PER_WORD] ^= T(1) << (b % BITS_PER_WORD);
+    }
+
+
+    void reset() noexcept {
+        std::fill(std::begin(storage), std::end(storage), 0);
+    }
+
+    bool operator[](size_t b) const noexcept {
+        assert_invariant(b / BITS_PER_WORD < N);
+        return bool(storage[b / BITS_PER_WORD] & (T(1) << (b % BITS_PER_WORD)));
+    }
+
+    size_t count() const noexcept {
+#if defined(TNT_UTILS_BITSET_USE_NEON)
+        if (BIT_COUNT % 128 == 0 && BIT_COUNT / 128 < 31) {
+            // Use NEON for bitset multiple of 128 bits.
+            // The intermediate computation can't handle more than 31*128 bits because
+            // intermediate counts must be 8 bits.
+            uint8x16_t const* const p = (uint8x16_t const*) storage;
+            uint8x16_t counts = vcntq_u8(p[0]);
+            for (size_t i = 1; i < BIT_COUNT / 128; ++i) {
+                counts += vcntq_u8(p[i]);
+            }
+            return vaddlvq_u8(counts);
+        } else
+#endif
+        {
+            T r = utils::popcount(storage[0]);
+            for (size_t i = 1; i < N; ++i) {
+                r += utils::popcount(storage[i]);
+            }
+            return r;
+        }
+    }
+
+    bool any() const noexcept {
+#if defined(TNT_UTILS_BITSET_USE_NEON)
+        if (BIT_COUNT % 128 == 0) {
+            uint64x2_t const* const p = (uint64x2_t const*) storage;
+            uint64x2_t r = p[0];
+            for (size_t i = 1; i < BIT_COUNT / 128; ++i) {
+                r |= p[i];
+            }
+            return bool(r[0] | r[1]);
+        } else
+#endif
+        {
+            T r = storage[0];
+            for (size_t i = 1; i < N; ++i) {
+                r |= storage[i];
+            }
+            return bool(r);
+        }
+    }
+
+    bool none() const noexcept {
+        return !any();
+    }
+
+    bool all() const noexcept {
+#if defined(TNT_UTILS_BITSET_USE_NEON)
+        if (BIT_COUNT % 128 == 0) {
+            uint64x2_t const* const p = (uint64x2_t const*) storage;
+            uint64x2_t r = p[0];
+            for (size_t i = 1; i < BIT_COUNT / 128; ++i) {
+                r &= p[i];
+            }
+            return T(~(r[0] & r[1])) == T(0);
+        } else
+#endif
+        {
+            T r = storage[0];
+            for (size_t i = 1; i < N; ++i) {
+                r &= storage[i];
+            }
+            return T(~r) == T(0);
+        }
+    }
+
+    bool operator!=(const bitset& b) const noexcept {
+#if defined(TNT_UTILS_BITSET_USE_NEON)
+        if (BIT_COUNT % 128 == 0) {
+            bitset temp(*this ^ b);
+            uint64x2_t const* const p = (uint64x2_t const*) temp.storage;
+            uint64x2_t r = p[0];
+            for (size_t i = 1; i < BIT_COUNT / 128; ++i) {
+                r |= p[i];
+            }
+            return bool(r[0] | r[1]);
+        } else
+#endif
+        {
+            T r = storage[0] ^ b.storage[0];
+            for (size_t i = 1; i < N; ++i) {
+                r |= storage[i] ^ b.storage[i];
+            }
+            return bool(r);
+        }
+    }
+
+    bool operator==(const bitset& b) const noexcept {
+        return !operator!=(b);
+    }
+
+    bitset& operator&=(const bitset& b) noexcept {
+#if defined(TNT_UTILS_BITSET_USE_NEON)
+        if (BIT_COUNT % 128 == 0) {
+            uint8x16_t* const p = (uint8x16_t*) storage;
+            uint8x16_t const* const q = (uint8x16_t const*) b.storage;
+            for (size_t i = 0; i < BIT_COUNT / 128; ++i) {
+                p[i] &= q[i];
+            }
+        } else
+#endif
+        {
+            for (size_t i = 0; i < N; ++i) {
+                storage[i] &= b.storage[i];
+            }
+        }
+        return *this;
+    }
+
+    bitset& operator|=(const bitset& b) noexcept {
+#if defined(TNT_UTILS_BITSET_USE_NEON)
+        if (BIT_COUNT % 128 == 0) {
+            uint8x16_t* const p = (uint8x16_t*) storage;
+            uint8x16_t const* const q = (uint8x16_t const*) b.storage;
+            for (size_t i = 0; i < BIT_COUNT / 128; ++i) {
+                p[i] |= q[i];
+            }
+        } else
+#endif
+        {
+            for (size_t i = 0; i < N; ++i) {
+                storage[i] |= b.storage[i];
+            }
+        }
+        return *this;
+    }
+
+    bitset& operator^=(const bitset& b) noexcept {
+#if defined(TNT_UTILS_BITSET_USE_NEON)
+        if (BIT_COUNT % 128 == 0) {
+            uint8x16_t* const p = (uint8x16_t*) storage;
+            uint8x16_t const* const q = (uint8x16_t const*) b.storage;
+            for (size_t i = 0; i < BIT_COUNT / 128; ++i) {
+                p[i] ^= q[i];
+            }
+        } else
+#endif
+        {
+            for (size_t i = 0; i < N; ++i) {
+                storage[i] ^= b.storage[i];
+            }
+        }
+        return *this;
+    }
+
+    bitset operator~() const noexcept {
+        bitset r;
+#if defined(TNT_UTILS_BITSET_USE_NEON)
+        if (BIT_COUNT % 128 == 0) {
+            uint8x16_t* const p = (uint8x16_t*) r.storage;
+            uint8x16_t const* const q = (uint8x16_t const*) storage;
+            for (size_t i = 0; i < BIT_COUNT / 128; ++i) {
+                p[i] = ~q[i];
+            }
+        } else
+#endif
+        {
+            for (size_t i = 0; i < N; ++i) {
+                r.storage[i] = ~storage[i];
+            }
+        }
+        return r;
+    }
+
+private:
+    friend bool operator<(bitset const& lhs, bitset const& rhs) noexcept {
+        return std::lexicographical_compare(
+                std::begin(lhs.storage), std::end(lhs.storage),
+                std::begin(rhs.storage), std::end(rhs.storage)
+        );
+    }
+
+    friend bitset operator&(const bitset& lhs, const bitset& rhs) noexcept {
+        return bitset(lhs) &= rhs;
+    }
+
+    friend bitset operator|(const bitset& lhs, const bitset& rhs) noexcept {
+        return bitset(lhs) |= rhs;
+    }
+
+    friend bitset operator^(const bitset& lhs, const bitset& rhs) noexcept {
+        return bitset(lhs) ^= rhs;
+    }
+};
+
+using bitset8 = bitset<uint8_t>;
+using bitset32 = bitset<uint32_t>;
+using bitset64 = bitset<uint64_t>;
+using bitset128 = bitset<uint64_t, 2>;
+using bitset256 = bitset<uint64_t, 4>;
+
+static_assert(sizeof(bitset8) == 1, "bitset8 isn't 8 bits!");
+static_assert(sizeof(bitset32) == 4, "bitset32 isn't 32 bits!");
+static_assert(sizeof(bitset64) == 8, "bitset64 isn't 64 bits!");
+static_assert(sizeof(bitset128) == 16, "bitset128 isn't 128 bits!");
+static_assert(sizeof(bitset256) == 32, "bitset256 isn't 256 bits!");
+
+} // namespace utils
+
+#endif // TNT_UTILS_BITSET_H

flutter_filament/windows/include/filament/utils/compiler.h

@@ -0,0 +1,263 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_COMPILER_H
+#define TNT_UTILS_COMPILER_H
+
+// compatibility with non-clang compilers...
+#ifndef __has_attribute
+#define __has_attribute(x) 0
+#endif
+
+#ifndef __has_feature
+#define __has_feature(x) 0
+#endif
+
+#ifndef __has_builtin
+#define __has_builtin(x) 0
+#endif
+
+#if __has_attribute(visibility)
+#    define UTILS_PUBLIC  __attribute__((visibility("default")))
+#else
+#    define UTILS_PUBLIC  
+#endif
+
+#if __has_attribute(deprecated)
+#   define UTILS_DEPRECATED [[deprecated]]
+#else
+#   define UTILS_DEPRECATED
+#endif
+
+#if __has_attribute(packed)
+#   define UTILS_PACKED __attribute__((packed))
+#else
+#   define UTILS_PACKED
+#endif
+
+#if __has_attribute(noreturn)
+#    define UTILS_NORETURN __attribute__((noreturn))
+#else
+#    define UTILS_NORETURN
+#endif
+
+#if __has_attribute(fallthrough)
+#   define UTILS_FALLTHROUGH [[fallthrough]]
+#else
+#   define UTILS_FALLTHROUGH
+#endif
+
+#if __has_attribute(visibility)
+#    ifndef TNT_DEV
+#        define UTILS_PRIVATE __attribute__((visibility("hidden")))
+#    else
+#        define UTILS_PRIVATE
+#    endif
+#else
+#    define UTILS_PRIVATE
+#endif
+
+#define UTILS_NO_SANITIZE_THREAD
+#if __has_feature(thread_sanitizer)
+#undef UTILS_NO_SANITIZE_THREAD
+#define UTILS_NO_SANITIZE_THREAD __attribute__((no_sanitize("thread")))
+#endif
+
+#define UTILS_HAS_SANITIZE_THREAD 0
+#if __has_feature(thread_sanitizer) || defined(__SANITIZE_THREAD__)
+#undef UTILS_HAS_SANITIZE_THREAD
+#define UTILS_HAS_SANITIZE_THREAD 1
+#endif
+
+#define UTILS_HAS_SANITIZE_MEMORY 0
+#if __has_feature(memory_sanitizer)
+#undef UTILS_HAS_SANITIZE_MEMORY
+#define UTILS_HAS_SANITIZE_MEMORY 1
+#endif
+
+/*
+ * helps the compiler's optimizer predicting branches
+ */
+#if __has_builtin(__builtin_expect)
+#   ifdef __cplusplus
+#      define UTILS_LIKELY( exp )    (__builtin_expect( !!(exp), true ))
+#      define UTILS_UNLIKELY( exp )  (__builtin_expect( !!(exp), false ))
+#   else
+#      define UTILS_LIKELY( exp )    (__builtin_expect( !!(exp), 1 ))
+#      define UTILS_UNLIKELY( exp )  (__builtin_expect( !!(exp), 0 ))
+#   endif
+#else
+#   define UTILS_LIKELY( exp )    (!!(exp))
+#   define UTILS_UNLIKELY( exp )  (!!(exp))
+#endif
+
+#if __has_builtin(__builtin_prefetch)
+#   define UTILS_PREFETCH( exp ) (__builtin_prefetch(exp))
+#else
+#   define UTILS_PREFETCH( exp )
+#endif
+
+#if __has_builtin(__builtin_assume)
+#   define UTILS_ASSUME( exp ) (__builtin_assume(exp))
+#else
+#   define UTILS_ASSUME( exp )
+#endif
+
+#if (defined(__i386__) || defined(__x86_64__))
+#   define UTILS_HAS_HYPER_THREADING 1      // on x86 we assume we have hyper-threading.
+#else
+#   define UTILS_HAS_HYPER_THREADING 0
+#endif
+
+#if defined(FILAMENT_SINGLE_THREADED)
+#   define UTILS_HAS_THREADING 0
+#elif defined(__EMSCRIPTEN__)
+#   if defined(__EMSCRIPTEN_PTHREADS__) && defined(FILAMENT_WASM_THREADS)
+#      define UTILS_HAS_THREADING 1
+#   else
+#      define UTILS_HAS_THREADING 0
+#   endif
+#else
+#   define UTILS_HAS_THREADING 1
+#endif
+
+#if __has_attribute(noinline)
+#define UTILS_NOINLINE __attribute__((noinline))
+#else
+#define UTILS_NOINLINE
+#endif
+
+#if __has_attribute(always_inline)
+#define UTILS_ALWAYS_INLINE __attribute__((always_inline))
+#else
+#define UTILS_ALWAYS_INLINE
+#endif
+
+#if __has_attribute(pure)
+#define UTILS_PURE __attribute__((pure))
+#else
+#define UTILS_PURE
+#endif
+
+#if __has_attribute(maybe_unused) || (defined(_MSC_VER) && _MSC_VER >= 1911)
+#define UTILS_UNUSED [[maybe_unused]]
+#define UTILS_UNUSED_IN_RELEASE [[maybe_unused]]
+#elif __has_attribute(unused)
+#define UTILS_UNUSED __attribute__((unused))
+#define UTILS_UNUSED_IN_RELEASE __attribute__((unused))
+#else
+#define UTILS_UNUSED
+#define UTILS_UNUSED_IN_RELEASE
+#endif
+
+#if defined(_MSC_VER) && _MSC_VER >= 1900
+#    define UTILS_RESTRICT __restrict
+#elif (defined(__clang__) || defined(__GNUC__))
+#    define UTILS_RESTRICT __restrict__
+#else
+#    define UTILS_RESTRICT
+#endif
+
+#if defined(_MSC_VER) && _MSC_VER >= 1900
+#   define UTILS_HAS_FEATURE_CXX_THREAD_LOCAL 1
+#elif __has_feature(cxx_thread_local)
+#   define UTILS_HAS_FEATURE_CXX_THREAD_LOCAL 1
+#else
+#   define UTILS_HAS_FEATURE_CXX_THREAD_LOCAL 0
+#endif
+
+#if defined(_MSC_VER)
+// MSVC does not support loop unrolling hints
+#   define UTILS_UNROLL
+#   define UTILS_NOUNROLL
+#else
+// C++11 allows pragmas to be specified as part of defines using the _Pragma syntax.
+#   define UTILS_UNROLL _Pragma("unroll")
+#   define UTILS_NOUNROLL _Pragma("nounroll")
+#endif
+
+#if __has_feature(cxx_rtti) || defined(_CPPRTTI)
+#   define UTILS_HAS_RTTI 1
+#else
+#   define UTILS_HAS_RTTI 0
+#endif
+
+#ifdef __ARM_ACLE
+#   include <arm_acle.h>
+#   define UTILS_WAIT_FOR_INTERRUPT()   __wfi()
+#   define UTILS_WAIT_FOR_EVENT()       __wfe()
+#   define UTILS_BROADCAST_EVENT()      __sev()
+#   define UTILS_SIGNAL_EVENT()         __sevl()
+#   define UTILS_PAUSE()                __yield()
+#   define UTILS_PREFETCHW(addr)        __pldx(1, 0, 0, addr)
+#else // !__ARM_ACLE
+#   if (defined(__i386__) || defined(__x86_64__))
+#       define UTILS_X86_PAUSE              {__asm__ __volatile__( "rep; nop" : : : "memory" );}
+#       define UTILS_WAIT_FOR_INTERRUPT()   UTILS_X86_PAUSE
+#       define UTILS_WAIT_FOR_EVENT()       UTILS_X86_PAUSE
+#       define UTILS_BROADCAST_EVENT()
+#       define UTILS_SIGNAL_EVENT()
+#       define UTILS_PAUSE()                UTILS_X86_PAUSE
+#       define UTILS_PREFETCHW(addr)        UTILS_PREFETCH(addr)
+#   else // !x86
+#       define UTILS_WAIT_FOR_INTERRUPT()
+#       define UTILS_WAIT_FOR_EVENT()
+#       define UTILS_BROADCAST_EVENT()
+#       define UTILS_SIGNAL_EVENT()
+#       define UTILS_PAUSE()
+#       define UTILS_PREFETCHW(addr)        UTILS_PREFETCH(addr)
+#   endif // x86
+#endif // __ARM_ACLE
+
+
+// ssize_t is a POSIX type.
+#if defined(WIN32) || defined(_WIN32)
+#include <Basetsd.h>
+typedef SSIZE_T ssize_t;
+#endif
+
+#ifdef _MSC_VER
+#   define UTILS_EMPTY_BASES __declspec(empty_bases)
+#else
+#   define UTILS_EMPTY_BASES
+#endif
+
+#if defined(WIN32) || defined(_WIN32)
+    #define IMPORTSYMB __declspec(dllimport)
+#else
+    #define IMPORTSYMB
+#endif
+
+#if defined(_MSC_VER) && !defined(__PRETTY_FUNCTION__)
+#    define __PRETTY_FUNCTION__ __FUNCSIG__
+#endif 
+
+
+#if defined(_MSC_VER)
+#   define UTILS_WARNING_PUSH _Pragma("warning( push )")
+#   define UTILS_WARNING_POP _Pragma("warning( pop )")
+#   define UTILS_WARNING_ENABLE_PADDED _Pragma("warning(1: 4324)")
+#elif defined(__clang__)
+#   define UTILS_WARNING_PUSH _Pragma("clang diagnostic push")
+#   define UTILS_WARNING_POP  _Pragma("clang diagnostic pop")
+#   define UTILS_WARNING_ENABLE_PADDED _Pragma("clang diagnostic warning \"-Wpadded\"")
+#else
+#   define UTILS_WARNING_PUSH
+#   define UTILS_WARNING_POP
+#   define UTILS_WARNING_ENABLE_PADDED
+#endif
+
+#endif // TNT_UTILS_COMPILER_H

flutter_filament/windows/include/filament/utils/compressed_pair.h

@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_COMPRESSED_PAIR_H
+#define TNT_UTILS_COMPRESSED_PAIR_H
+
+#include <type_traits>
+#include <utility>
+
+namespace utils {
+
+template<typename T, bool>
+struct dependent_type : public T {
+};
+
+template<typename T1, typename T2,
+        std::enable_if_t<!std::is_same_v<T1, T2>, bool> = true>
+struct compressed_pair : private T1, private T2 {
+
+    template<bool Dummy = true, typename = std::enable_if_t<
+            dependent_type<std::is_default_constructible<T1>, Dummy>::value &&
+            dependent_type<std::is_default_constructible<T2>, Dummy>::value>>
+    compressed_pair() : T1(), T2() {}
+
+    template<typename U1, typename U2>
+    compressed_pair(U1&& other1, U2&& other2)
+            : T1(std::forward<U1>(other1)),
+              T2(std::forward<U2>(other2)) {}
+
+    T1& first() noexcept {
+        return static_cast<T1&>(*this);
+    }
+
+    T2& second() noexcept {
+        return static_cast<T2&>(*this);
+    }
+
+    T1 const& first() const noexcept {
+        return static_cast<T1 const&>(*this);
+    }
+
+    T2 const& second() const noexcept {
+        return static_cast<T2 const&>(*this);
+    }
+
+    void swap(compressed_pair& other) noexcept {
+        using std::swap;
+        swap(first(), other.first());
+        swap(second(), other.second());
+    }
+};
+
+} // namespace utils
+
+#endif // TNT_UTILS_COMPRESSED_PAIR_H

flutter_filament/windows/include/filament/utils/debug.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_DEBUG_H
+#define TNT_UTILS_DEBUG_H
+
+#include <utils/compiler.h>
+
+namespace utils {
+void panic(const char *func, const char * file, int line, const char *assertion) noexcept;
+} // namespace filament
+
+#ifdef NDEBUG
+#   define	assert_invariant(e)	((void)0)
+#else
+#   define	assert_invariant(e) \
+            (UTILS_LIKELY(e) ? ((void)0) : utils::panic(__func__, __FILE__, __LINE__, #e))
+#endif // NDEBUG
+
+#endif // TNT_UTILS_DEBUG_H

flutter_filament/windows/include/filament/utils/generic/Mutex.h

@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_GENERIC_MUTEX_H
+#define TNT_UTILS_GENERIC_MUTEX_H
+
+#include <mutex>
+
+namespace utils {
+
+using Mutex = std::mutex;
+
+} // namespace utils
+
+#endif // TNT_UTILS_GENERIC_MUTEX_H

flutter_filament/windows/include/filament/utils/memalign.h

@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_MEMALIGN_H
+#define TNT_UTILS_MEMALIGN_H
+
+#include <type_traits>
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdlib.h>
+
+#if defined(WIN32)
+#include <malloc.h>
+#endif
+
+namespace utils {
+
+inline void* aligned_alloc(size_t size, size_t align) noexcept {
+    // 'align' must be a power of two and a multiple of sizeof(void*)
+    align = (align < sizeof(void*)) ? sizeof(void*) : align;
+    assert(align && !(align & align - 1));
+    assert((align % sizeof(void*)) == 0);
+
+    void* p = nullptr;
+
+#if defined(WIN32)
+    p = ::_aligned_malloc(size, align);
+#else
+    ::posix_memalign(&p, align, size);
+#endif
+    return p;
+}
+
+inline void aligned_free(void* p) noexcept {
+#if defined(WIN32)
+    ::_aligned_free(p);
+#else
+    ::free(p);
+#endif
+}
+
+/*
+ * This allocator can be used with std::vector for instance to ensure all items are aligned
+ * to their alignof(). e.g.
+ *
+ *      template<typename T>
+ *      using aligned_vector = std::vector<T, utils::STLAlignedAllocator<T>>;
+ *
+ *      aligned_vector<Foo> foos;
+ *
+ */
+template<typename TYPE>
+class STLAlignedAllocator {
+    static_assert(!(alignof(TYPE) & (alignof(TYPE) - 1)), "alignof(T) must be a power of two");
+
+public:
+    using value_type = TYPE;
+    using pointer = TYPE*;
+    using const_pointer = const TYPE*;
+    using reference = TYPE&;
+    using const_reference = const TYPE&;
+    using size_type = std::size_t;
+    using difference_type = std::ptrdiff_t;
+    using propagate_on_container_move_assignment = std::true_type;
+    using is_always_equal = std::true_type;
+
+    template<typename T>
+    struct rebind { using other = STLAlignedAllocator<T>; };
+
+    inline STLAlignedAllocator() noexcept = default;
+
+    template<typename T>
+    inline explicit STLAlignedAllocator(const STLAlignedAllocator<T>&) noexcept {}
+
+    inline ~STLAlignedAllocator() noexcept = default;
+
+    inline pointer allocate(size_type n) noexcept {
+        return (pointer)aligned_alloc(n * sizeof(value_type), alignof(TYPE));
+    }
+
+    inline void deallocate(pointer p, size_type) {
+        aligned_free(p);
+    }
+
+    // stateless allocators are always equal
+    template<typename T>
+    bool operator==(const STLAlignedAllocator<T>&) const noexcept {
+        return true;
+    }
+
+    template<typename T>
+    bool operator!=(const STLAlignedAllocator<T>&) const noexcept {
+        return false;
+    }
+};
+
+} // namespace utils
+
+#endif // TNT_UTILS_MEMALIGN_H

flutter_filament/windows/include/filament/utils/ostream.h

@@ -0,0 +1,140 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_UTILS_OSTREAM_H
+#define TNT_UTILS_OSTREAM_H
+
+#include <utils/bitset.h>
+#include <utils/compiler.h>
+#include <utils/PrivateImplementation.h>
+
+#include <string>
+#include <string_view>
+#include <utility>
+
+namespace utils::io {
+
+struct ostream_;
+
+class UTILS_PUBLIC  ostream : protected utils::PrivateImplementation<ostream_> {
+    friend struct ostream_;
+
+public:
+    virtual ~ostream();
+
+    ostream& operator<<(short value) noexcept;
+    ostream& operator<<(unsigned short value) noexcept;
+
+    ostream& operator<<(char value) noexcept;
+    ostream& operator<<(unsigned char value) noexcept;
+
+    ostream& operator<<(int value) noexcept;
+    ostream& operator<<(unsigned int value) noexcept;
+
+    ostream& operator<<(long value) noexcept;
+    ostream& operator<<(unsigned long value) noexcept;
+
+    ostream& operator<<(long long value) noexcept;
+    ostream& operator<<(unsigned long long value) noexcept;
+
+    ostream& operator<<(float value) noexcept;
+    ostream& operator<<(double value) noexcept;
+    ostream& operator<<(long double value) noexcept;
+
+    ostream& operator<<(bool value) noexcept;
+
+    ostream& operator<<(const void* value) noexcept;
+
+    ostream& operator<<(const char* string) noexcept;
+    ostream& operator<<(const unsigned char* string) noexcept;
+
+    ostream& operator<<(std::string const& s) noexcept;
+    ostream& operator<<(std::string_view const& s) noexcept;
+
+    ostream& operator<<(ostream& (* f)(ostream&)) noexcept { return f(*this); }
+
+    ostream& dec() noexcept;
+    ostream& hex() noexcept;
+
+protected:
+    ostream& print(const char* format, ...) noexcept;
+
+    class Buffer {
+    public:
+        Buffer() noexcept;
+        ~Buffer() noexcept;
+
+        Buffer(const Buffer&) = delete;
+        Buffer& operator=(const Buffer&) = delete;
+
+        const char* get() const noexcept { return buffer; }
+
+        std::pair<char*, size_t> grow(size_t s) noexcept;
+        void advance(ssize_t n) noexcept;
+        void reset() noexcept;
+
+    private:
+        void reserve(size_t newSize) noexcept;
+
+        char* buffer = nullptr;     // buffer address
+        char* curr = nullptr;       // current pointer
+        size_t size = 0;            // size remaining
+        size_t capacity = 0;        // total capacity of the buffer
+    };
+
+    Buffer& getBuffer() noexcept;
+    Buffer const& getBuffer() const noexcept;
+
+private:
+    virtual ostream& flush() noexcept = 0;
+
+    friend ostream& hex(ostream& s) noexcept;
+    friend ostream& dec(ostream& s) noexcept;
+    friend ostream& endl(ostream& s) noexcept;
+    friend ostream& flush(ostream& s) noexcept;
+
+    enum type {
+        SHORT, USHORT, CHAR, UCHAR, INT, UINT, LONG, ULONG, LONG_LONG, ULONG_LONG, FLOAT, DOUBLE,
+        LONG_DOUBLE
+    };
+
+    const char* getFormat(type t) const noexcept;
+};
+
+// handles utils::bitset
+inline ostream& operator << (ostream& o, utils::bitset32 const& s) noexcept {
+    return o << (void*)uintptr_t(s.getValue());
+}
+
+// handles vectors from libmath (but we do this generically, without needing a dependency on libmath)
+template<template<typename T> class VECTOR, typename T>
+inline ostream& operator<<(ostream& stream, const VECTOR<T>& v) {
+    stream << "< ";
+    for (size_t i = 0; i < v.size() - 1; i++) {
+        stream << v[i] << ", ";
+    }
+    stream << v[v.size() - 1] << " >";
+    return stream;
+}
+
+inline ostream& hex(ostream& s) noexcept { return s.hex(); }
+inline ostream& dec(ostream& s) noexcept { return s.dec(); }
+inline ostream& endl(ostream& s) noexcept { s << '\n'; return s.flush(); }
+inline ostream& flush(ostream& s) noexcept { return s.flush(); }
+
+} // namespace utils::io
+
+#endif // TNT_UTILS_OSTREAM_H

flutter_filament/windows/include/filament/utils/unwindows.h

@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#if defined (WIN32)
+
+#ifdef max
+#undef max
+#endif
+
+#ifdef min
+#undef min
+#endif
+
+#ifdef far
+#undef far
+#endif
+
+#ifdef near
+#undef near
+#endif
+
+#ifdef ERROR
+#undef ERROR
+#endif
+
+#ifdef OPAQUE
+#undef OPAQUE
+#endif
+
+#ifdef TRANSPARENT
+#undef TRANSPARENT
+#endif
+
+#ifdef PURE
+#undef PURE
+#endif
+
+#endif