restructure render loop to correct timings and expose FFI methods for setBoneTransform/setMorphWeights

ios/include/AssetManager.hpp

@@ -92,6 +92,9 @@ namespace polyvox
         bool hide(EntityId entity, const char *meshName);
         bool reveal(EntityId entity, const char *meshName);
         const char *getNameForEntity(EntityId entityId);
+        utils::Entity findChildEntityByName(
+            EntityId entityId,
+            const char *entityName);
 
     private:
         AssetLoader *_assetLoader = nullptr;
@@ -108,6 +111,8 @@ namespace polyvox
         vector<SceneAsset> _assets;
         tsl::robin_map<EntityId, int> _entityIdLookup;
 
+        
+
         utils::Entity findEntityByName(
             SceneAsset asset,
             const char *entityName);

ios/include/FlutterFilamentApi.h

@@ -168,6 +168,7 @@ extern "C"
 	FLUTTER_PLUGIN_EXPORT void set_post_processing(void *const viewer, bool enabled);
 	FLUTTER_PLUGIN_EXPORT void pick(void *const viewer, int x, int y, EntityId *entityId);
 	FLUTTER_PLUGIN_EXPORT const char *get_name_for_entity(void *const assetManager, const EntityId entityId);
+	FLUTTER_PLUGIN_EXPORT const EntityId find_child_entity_by_name(void *const assetManager, const EntityId parent, const char* name);
 	FLUTTER_PLUGIN_EXPORT void ios_dummy();
 	FLUTTER_PLUGIN_EXPORT void flutter_filament_free(void *ptr);
 #ifdef __cplusplus

ios/include/FlutterFilamentFFIApi.h

@@ -58,6 +58,18 @@ FLUTTER_PLUGIN_EXPORT int get_animation_count_ffi(void* const assetManager, Enti
 FLUTTER_PLUGIN_EXPORT void get_animation_name_ffi(void* const assetManager, EntityId asset, char *const outPtr, int index);
 FLUTTER_PLUGIN_EXPORT void get_morph_target_name_ffi(void* const assetManager, EntityId asset, const char *meshName, char *const outPtr, int index);
 FLUTTER_PLUGIN_EXPORT int get_morph_target_name_count_ffi(void* const assetManager, EntityId asset, const char *meshName);
+FLUTTER_PLUGIN_EXPORT void set_morph_target_weights_ffi(void* const assetManager,
+                                                        EntityId asset,
+                                                        const char *const entityName,
+                                                        const float *const morphData,
+                                                        int numWeights
+                                                        );
+FLUTTER_PLUGIN_EXPORT bool set_bone_transform_ffi(
+		void *assetManager,
+		EntityId asset,
+		const char *entityName,
+		const float *const transform,
+		const char *boneName);
 FLUTTER_PLUGIN_EXPORT void set_post_processing_ffi(void* const viewer, bool enabled);
 FLUTTER_PLUGIN_EXPORT void pick_ffi(void* const viewer, int x, int y, EntityId* entityId);
 FLUTTER_PLUGIN_EXPORT void ios_dummy_ffi();

ios/src/AssetManager.cpp

@@ -280,16 +280,6 @@ namespace polyvox
         return _assets[pos->second].asset;
     }
 
-    // vector<int> completedBoneAnimations;
-
-    //         for (int i = completed.size() - 1; i >= 0; i--) {
-    //             auto completedAnimationIndex = completed[i];
-    //             if(asset.animations.mType == AnimationType::BONE) {
-    //                 completedBoneAnimations.push_back()
-    //             }
-    //             (completedAnimationIndex);
-    //         }
-
     void AssetManager::updateAnimations()
     {
 
@@ -390,10 +380,13 @@ namespace polyvox
         }
     }
 
+    // TODO - we really don't want to be looking up the bone index/entity by name every single frame
+    // - could use findChildEntityByName 
+    // - or is it better to add an option for "streaming" mode where we can just return a reference to a mat4 and then update the values directly?
     bool AssetManager::setBoneTransform(EntityId entityId, const char *entityName, int32_t skinIndex, const char* boneName, math::mat4f localTransform)
     {
 
-        Log("Setting transform for bone %s/skin %d for mesh target %s", boneName, skinIndex, entityName);
+        std::lock_guard lock(_animationMutex);
 
         const auto &pos = _entityIdLookup.find(entityId);
         if (pos == _entityIdLookup.end())
@@ -414,6 +407,11 @@ namespace polyvox
 
         const auto &renderableInstance = rm.getInstance(entity);
 
+        if(!renderableInstance.isValid()) {
+            Log("Invalid renderable");
+            return false;
+        }
+
         TransformManager &transformManager = _engine->getTransformManager();
 
         const auto &filamentInstance = sceneAsset.asset->getInstance();
@@ -442,6 +440,7 @@ namespace polyvox
             return false;
         }
 
+
         utils::Entity joint = filamentInstance->getJointsAt(skinIndex)[boneIndex];
 
         if (joint.isNull())
@@ -577,6 +576,28 @@ namespace polyvox
             count);
     }
 
+    utils::Entity AssetManager::findChildEntityByName(EntityId entityId, const char *entityName) {
+        std::lock_guard lock(_animationMutex);
+
+        const auto &pos = _entityIdLookup.find(entityId);
+        if (pos == _entityIdLookup.end())
+        {
+            Log("Couldn't find asset under specified entity id.");
+            return utils::Entity();
+        }
+        SceneAsset &sceneAsset = _assets[pos->second];
+
+        const auto entity = findEntityByName(sceneAsset, entityName);
+
+        if(entity.isNull()) {
+            Log("Failed to find entity %s.", entityName);
+        }
+        
+        return entity;
+
+    }
+
+
     utils::Entity AssetManager::findEntityByName(SceneAsset asset, const char *entityName)
     {
         utils::Entity entity;

ios/src/FilamentViewer.cpp

@@ -962,6 +962,7 @@ namespace polyvox
 
   double _elapsed = 0;
   int _frameCount = 0;
+  int _skippedFrames = 0;
 
   void FilamentViewer::render(
       uint64_t frameTimeInNanos,
@@ -981,6 +982,7 @@ namespace polyvox
       // Log("1 sec average for asset animation update %f", _elapsed / 60);
       _elapsed = 0;
       _frameCount = 0;
+      Log("Skipped frames : %d", _skippedFrames);
     }
 
     Timer tmr;
@@ -1023,6 +1025,8 @@ namespace polyvox
     }
     else
     {
+      _skippedFrames++;
+
       // std::cout << "Skipped" << std::endl;
       // skipped frame
     }

ios/src/FlutterFilamentFFIApi.cpp

@@ -16,24 +16,36 @@ class RenderLoop {
 public:
   explicit RenderLoop() {
     _t = new std::thread([this]() {
+      auto last = std::chrono::high_resolution_clock::now();
       while (!_stop) {
-        {
+
-          if (_rendering) {
+        auto now = std::chrono::high_resolution_clock::now();
-            doRender();
+
-          }
+        float elapsed = float(std::chrono::duration_cast<std::chrono::milliseconds>(now - last).count());
-        }
+
+        while(elapsed < 3 * _frameIntervalInMilliseconds / 4) {
+          
           std::function<void()> task;
-        {
           std::unique_lock<std::mutex> lock(_access);
           if (_tasks.empty()) {
-            _cond.wait_for(lock, std::chrono::duration<float, std::milli>(
+            _cond.wait_for(lock, std::chrono::duration<float, std::milli>(1));
-                                     _frameIntervalInMilliseconds));
+            now = std::chrono::high_resolution_clock::now();
+            elapsed = float(std::chrono::duration_cast<std::chrono::milliseconds>(now - last).count());
             continue;
           }
           task = std::move(_tasks.front());
           _tasks.pop_front();
-        }
           task();
+          
+          now = std::chrono::high_resolution_clock::now();
+          elapsed = float(std::chrono::duration_cast<std::chrono::milliseconds>(now - last).count());
+        }
+
+        if (_rendering) {
+          doRender();
+        }
+
+        last = now;
       }
     });
   }
@@ -428,5 +440,29 @@ get_name_for_entity_ffi(void *const assetManager, const EntityId entityId) {
   return fut.get();
 }
 
+void set_morph_target_weights_ffi(void *const assetManager, 
+                                  EntityId asset,
+                                  const char *const entityName,
+                                  const float *const morphData,
+                                  int numWeights) {
+    std::packaged_task<void()> lambda(
+      [&] { return set_morph_target_weights(assetManager, asset, entityName, morphData, numWeights); });
+      auto fut = _rl->add_task(lambda);
+      fut.wait();
+}
+
+FLUTTER_PLUGIN_EXPORT bool set_bone_transform_ffi(
+		void *assetManager,
+		EntityId asset,
+		const char *entityName,
+		const float *const transform,
+		const char *boneName) {
+      std::packaged_task<bool()> lambda(
+      [&] { return set_bone_transform(assetManager, asset, entityName, transform, boneName); });
+      auto fut = _rl->add_task(lambda);
+      fut.wait();
+      return fut.get();
+}
+
 FLUTTER_PLUGIN_EXPORT void ios_dummy_ffi() { Log("Dummy called"); }
 }

lib/filament_controller.dart

@@ -485,4 +485,11 @@ abstract class FilamentController {
       double orbitSpeedX = 0.01,
       double orbitSpeedY = 0.01,
       double zoomSpeed = 0.01});
+
+  ///
+  /// Finds the child entity named [childName] associated with the given parent.
+  /// Usually, [parent] will be the return value from [loadGlb]/[loadGltf] and [childName] will be the name of a node/mesh.
+  ///
+  Future<FilamentEntity> getChildEntity(
+      FilamentEntity parent, String childName);
 }

lib/filament_controller_ffi.dart

@@ -125,7 +125,9 @@ class FilamentControllerFFI extends FilamentController {
 
   @override
   Future setFrameRate(int framerate) async {
-    set_frame_interval_ffi(1.0 / framerate);
+    final interval = 1000.0 / framerate;
+    set_frame_interval_ffi(interval);
+    dev.log("Set frame interval to $interval");
   }
 
   @override
@@ -596,7 +598,7 @@ class FilamentControllerFFI extends FilamentController {
       weightsPtr.elementAt(i).value = weights[i];
     }
     var meshNamePtr = meshName.toNativeUtf8(allocator: calloc).cast<Char>();
-    set_morph_target_weights(
+    set_morph_target_weights_ffi(
         _assetManager!, entity, meshNamePtr, weightsPtr, weights.length);
     calloc.free(weightsPtr);
     calloc.free(meshNamePtr);
@@ -1178,7 +1180,7 @@ class FilamentControllerFFI extends FilamentController {
     var meshNamePtr = meshName.toNativeUtf8(allocator: calloc).cast<Char>();
     var boneNamePtr = boneName.toNativeUtf8(allocator: calloc).cast<Char>();
 
-    var result = set_bone_transform(
+    var result = set_bone_transform_ffi(
         _assetManager!, entity, meshNamePtr, ptr, boneNamePtr);
 
     calloc.free(ptr);
@@ -1188,4 +1190,21 @@ class FilamentControllerFFI extends FilamentController {
       throw Exception("Failed to set bone transform. See logs for details");
     }
   }
+
+  @override
+  Future<FilamentEntity> getChildEntity(
+      FilamentEntity parent, String childName) async {
+    var childNamePtr = childName.toNativeUtf8(allocator: calloc).cast<Char>();
+    try {
+      var childEntity =
+          find_child_entity_by_name(_assetManager!, parent, childNamePtr);
+      if (childEntity == _FILAMENT_ASSET_ERROR) {
+        throw Exception(
+            "Could not find child ${childName} under the specified entity");
+      }
+      return childEntity;
+    } finally {
+      calloc.free(childNamePtr);
+    }
+  }
 }

lib/generated_bindings.dart

@@ -736,6 +736,16 @@ external ffi.Pointer<ffi.Char> get_name_for_entity(
   int entityId,
 );
 
+@ffi.Native<
+        EntityId Function(
+            ffi.Pointer<ffi.Void>, EntityId, ffi.Pointer<ffi.Char>)>(
+    symbol: 'find_child_entity_by_name', assetId: 'flutter_filament_plugin')
+external int find_child_entity_by_name(
+  ffi.Pointer<ffi.Void> assetManager,
+  int parent,
+  ffi.Pointer<ffi.Char> name,
+);
+
 @ffi.Native<ffi.Void Function()>(
     symbol: 'ios_dummy', assetId: 'flutter_filament_plugin')
 external void ios_dummy();
@@ -1092,6 +1102,34 @@ external int get_morph_target_name_count_ffi(
   ffi.Pointer<ffi.Char> meshName,
 );
 
+@ffi.Native<
+        ffi.Void Function(ffi.Pointer<ffi.Void>, EntityId,
+            ffi.Pointer<ffi.Char>, ffi.Pointer<ffi.Float>, ffi.Int)>(
+    symbol: 'set_morph_target_weights_ffi', assetId: 'flutter_filament_plugin')
+external void set_morph_target_weights_ffi(
+  ffi.Pointer<ffi.Void> assetManager,
+  int asset,
+  ffi.Pointer<ffi.Char> entityName,
+  ffi.Pointer<ffi.Float> morphData,
+  int numWeights,
+);
+
+@ffi.Native<
+        ffi.Bool Function(
+            ffi.Pointer<ffi.Void>,
+            EntityId,
+            ffi.Pointer<ffi.Char>,
+            ffi.Pointer<ffi.Float>,
+            ffi.Pointer<ffi.Char>)>(
+    symbol: 'set_bone_transform_ffi', assetId: 'flutter_filament_plugin')
+external bool set_bone_transform_ffi(
+  ffi.Pointer<ffi.Void> assetManager,
+  int asset,
+  ffi.Pointer<ffi.Char> entityName,
+  ffi.Pointer<ffi.Float> transform,
+  ffi.Pointer<ffi.Char> boneName,
+);
+
 @ffi.Native<ffi.Void Function(ffi.Pointer<ffi.Void>, ffi.Bool)>(
     symbol: 'set_post_processing_ffi', assetId: 'flutter_filament_plugin')
 external void set_post_processing_ffi(