Revert "preview changes"

This reverts commit 98f5cbe309.

apps/LoopThroughWithOpenGLCompositing/gl/OpenGLComposite.h

@@ -23,6 +23,7 @@
 #include <string>
 #include <vector>
 #include <deque>
+#include <chrono>
 
 class VideoIODevice;
 class OpenGLVideoIOBridge;
@@ -64,7 +65,7 @@ public:
 	std::string GetOscAddress() const;
 
 	void resizeGL(WORD width, WORD height);
-	void paintGL();
+	void paintGL(bool force = false);
 
 private:
 	void resizeWindow(int width, int height);
@@ -92,6 +93,7 @@ private:
 	unsigned								mCachedRenderStateHeight = 0;
 	std::atomic<bool>						mUseCommittedLayerStates;
 	std::atomic<bool>						mScreenshotRequested;
+	std::chrono::steady_clock::time_point	mLastPreviewPresentTime;
 
 	bool InitOpenGLState();
 	void renderEffect();