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Differential Revision: D81034847

Author: Bartlomiej Bloniarz

packages/react-native/ReactCommon/react/renderer/animated/NativeAnimatedNodesManager.cpp

@@ -89,6 +89,7 @@ NativeAnimatedNodesManager::NativeAnimatedNodesManager(
     LOG(ERROR)
         << "C++ Animated was setup without a way to update UI. Animations will not work.";
   }
+  // shouldn't be initialized here, but it's convenient for now
   animationBackend_ = std::make_shared<AnimationBackend>(
       startOnRenderCallback_,
       stopOnRenderCallback_,

packages/react-native/ReactCommon/react/renderer/animationbackend/AnimationBackend.cpp

@@ -17,12 +17,10 @@ AnimationBackend::AnimationBackend(
       stopOnRenderCallback_(stopOnRenderCallback),
       directManipulationCallback_(directManipulationCallback) {}
 
-void AnimationBackend::onTick() {
-  // std::unordered_map<Tag, folly::dynamic> updates;
+void AnimationBackend::onAnimationFrame(double timestamp) {
   for (auto& callback : callbacks) {
-    auto muatations = callback(0.0);
+    auto muatations = callback(timestamp);
     for (auto& mutation : muatations) {
-      // updates[mutation.tag] =
       directManipulationCallback_(
           mutation.tag, folly::dynamic::object("opacity", mutation.opacity));
     }
@@ -31,7 +29,8 @@ void AnimationBackend::onTick() {
 
 void AnimationBackend::start(const Callback& callback) {
   callbacks.push_back(callback);
-  startOnRenderCallback_([this]() { onTick(); });
+  // startOnRenderCallback_ should provide the timestamp from the platform
+  startOnRenderCallback_([this]() { onAnimationFrame(0); });
 }
 void AnimationBackend::stop() {
   stopOnRenderCallback_();

packages/react-native/ReactCommon/react/renderer/animationbackend/AnimationBackend.h

@@ -20,7 +20,6 @@ struct AnimationMutation {
 };
 
 using AnimationMutations = std::vector<AnimationMutation>;
-
 using Callback = std::function<AnimationMutations(float)>;
 using StartOnRenderCallback = std::function<void(std::function<void()>&&)>;
 using StopOnRenderCallback = std::function<void()>;
@@ -38,7 +37,7 @@ class AnimationBackend {
       const StartOnRenderCallback& startOnRenderCallback,
       const StopOnRenderCallback& stopOnRenderCallback,
       const DirectManipulationCallback& directManipulationCallback);
-  void onTick();
+  void onAnimationFrame(double timestamp);
   void start(const Callback& callback);
   void stop();
 };