initial work to split into dart_filament and flutter_filament

dart_filament/native/include/ResourceBuffer.hpp

@@ -0,0 +1,110 @@
+#ifndef RESOURCE_BUFFER_H
+#define RESOURCE_BUFFER_H
+
+#include <stdint.h>
+#include <stdlib.h>
+
+//
+// A ResourceBuffer is a unified interface for working with
+// binary assets across various platforms.
+// This is simply:
+// 1) a pointer to some data
+// 2) the length of the data
+// 3) an ID that can be passed back to the native platform to release the underlying asset when needed.
+//
+struct ResourceBuffer
+{
+  const void *const data;
+  const int32_t size;
+  const int32_t id;
+
+#if defined(__cplusplus)
+  ResourceBuffer(void *const data, int32_t size, int32_t id) : data(data), size(size), id(id) {}
+#endif
+};
+
+typedef struct ResourceBuffer ResourceBuffer;
+typedef void (*LoadFilamentResourceIntoOutPointer)(const char *uri, ResourceBuffer *out);
+typedef ResourceBuffer (*LoadFilamentResource)(const char *uri);
+typedef ResourceBuffer (*LoadFilamentResourceFromOwner)(const char *const, void *const owner);
+typedef void (*FreeFilamentResource)(ResourceBuffer);
+typedef void (*FreeFilamentResourceFromOwner)(ResourceBuffer, void *const owner);
+
+struct ResourceLoaderWrapper
+{
+  LoadFilamentResource loadResource;
+  FreeFilamentResource freeResource;
+  LoadFilamentResourceFromOwner loadFromOwner;
+  FreeFilamentResourceFromOwner freeFromOwner;
+  void *owner;
+  LoadFilamentResourceIntoOutPointer loadToOut;
+};
+typedef struct ResourceLoaderWrapper ResourceLoaderWrapper;
+
+#if defined(__cplusplus)
+
+#include <thread>
+using namespace std::chrono_literals;
+namespace flutter_filament
+{
+
+  struct ResourceLoaderWrapperImpl : public ResourceLoaderWrapper
+  {
+
+    ResourceLoaderWrapperImpl(LoadFilamentResource loader, FreeFilamentResource freeResource)
+    {
+      loadFromOwner = nullptr;
+      freeFromOwner = nullptr;
+      loadResource = loader;
+      freeResource = freeResource;
+      owner = nullptr;
+    }
+
+    ResourceLoaderWrapperImpl(LoadFilamentResourceFromOwner loader, FreeFilamentResourceFromOwner freeResource, void *owner)
+    {
+      loadResource = nullptr;
+      freeResource = nullptr;
+      loadFromOwner = loader;
+      freeFromOwner = freeResource;
+      owner = owner;
+    }
+
+    ResourceBuffer load(const char *uri) const
+    {
+      if (loadToOut)
+      {
+        ResourceBuffer rb(nullptr, 0, -1);
+        loadToOut(uri, &rb);
+        while (rb.size == 0)
+        {
+          std::this_thread::sleep_for(100ms);
+        }
+
+        return rb;
+      }
+      else if (loadFromOwner)
+      {
+        auto rb = loadFromOwner(uri, owner);
+        return rb;
+      }
+      auto rb = loadResource(uri);
+      return rb;
+    }
+
+    void free(ResourceBuffer rb) const
+    {
+      if (freeFromOwner)
+      {
+        freeFromOwner(rb, owner);
+      }
+      else
+      {
+        freeResource(rb);
+      }
+    }
+  };
+
+}
+#endif
+
+#endif