Report the actual GPU framerate rather than the main thread submit rate when using the filament renderer.

PiperOrigin-RevId: 838775463
Change-Id: If66644d284a4a9e0263cf31bfbd1785b18e0209b

src/experimental/platform/renderer.cc

@@ -57,17 +57,6 @@ void Renderer::Render(const mjModel* model, mjData* data,
 
   mjrRect main_viewport = {0, 0, width, height};
   mjr_render(main_viewport, data ? &scene_ : nullptr, &render_context_);
-
-  auto now = std::chrono::steady_clock::now();
-  auto delta_time = now - last_fps_update_;
-  const double interval = std::chrono::duration<double>(delta_time).count();
-
-  ++frames_;
-  if (interval > 0.2) {  // only update FPS stat at most 5 times per second
-    last_fps_update_ = now;
-    fps_ = frames_ / interval;
-    frames_ = 0;
-  }
 }
 
 void Renderer::SaveScreenshot(const std::string& filename, int width,

src/experimental/platform/renderer.h

@@ -54,15 +54,10 @@ class Renderer {
   // Rendering flags.
   mjtByte* GetRenderFlags() { return scene_.flags; }
 
-  // Returns the current, average frame rate.
-  double GetFrameRate() const { return fps_; }
-
   // Returns the render context.
   const mjrContext& GetContext() const { return render_context_; }
 
  private:
-  using TimePoint = std::chrono::time_point<std::chrono::steady_clock>;
-
   // Resets the renderer; no rendering will occur until Init() is called again.
   void Deinit();
 
@@ -70,10 +65,6 @@ class Renderer {
   mjrContext render_context_;
   mjvScene scene_;
   bool initialized_ = false;
-
-  int frames_ = 0;
-  TimePoint last_fps_update_;
-  double fps_ = 0;
 };
 
 }  // namespace mujoco::platform