bugfix(gui): Fix black fade out at the end of the map load screen

Core/GameEngine/Include/Common/FramePacer.h

@@ -39,6 +39,7 @@ class FramePacer
 	~FramePacer();
 
 	void update(); ///< Signal that the app/render update is done and wait for the fps limit if applicable.
+	void reset(); ///< Move the frame timing anchor to now and predict the next update time from the target frame rate. Call after a long blocking operation so its duration does not leak into the next frame delta.
 
 	void setFramesPerSecondLimit( Int fps ); ///< Set the update fps limit.
 	Int  getFramesPerSecondLimit() const; ///< Get the update fps limit.

Core/GameEngine/Include/Common/FrameRateLimit.h

@@ -27,6 +27,7 @@ class FrameRateLimit
 	FrameRateLimit();
 
 	Real wait(UnsignedInt maxFps);
+	void reset(); ///< Move the timing anchor to now, discarding any time elapsed since the last call to wait.
 
 private:
 	Int64 m_freq;

Core/GameEngine/Source/Common/FramePacer.cpp

@@ -58,6 +58,12 @@ void FramePacer::update()
 	m_updateTime = m_frameRateLimit.wait(maxFps);
 }
 
+void FramePacer::reset()
+{
+	m_frameRateLimit.reset();
+	m_updateTime = 1.0f / (Real)getActualFramesPerSecondLimit();
+}
+
 void FramePacer::setFramesPerSecondLimit( Int fps )
 {
 	DEBUG_LOG(("FramePacer::setFramesPerSecondLimit() - setting max fps to %d (TheGlobalData->m_useFpsLimit == %d)", fps, TheGlobalData->m_useFpsLimit));

Core/GameEngine/Source/Common/FrameRateLimit.cpp

@@ -58,6 +58,13 @@ Real FrameRateLimit::wait(UnsignedInt maxFps)
 	return (Real)elapsedSeconds;
 }
 
+void FrameRateLimit::reset()
+{
+	LARGE_INTEGER tick;
+	QueryPerformanceCounter(&tick);
+	m_start = tick.QuadPart;
+}
+
 
 const UnsignedInt RenderFpsPreset::s_fpsValues[] = {
 	30, 50, 56, 60, 65, 70, 72, 75, 80, 85, 90, 100, 110, 120, 144, 240, 480, UncappedFpsValue };

GeneralsMD/Code/GameEngine/Source/GameLogic/System/GameLogic.cpp

@@ -2239,6 +2239,7 @@ void GameLogic::tryStartNewGame( Bool loadingSaveGame )
 	// if we're in a load game, don't fade yet
 	if(loadingSaveGame == FALSE && TheTransitionHandler != nullptr && m_loadScreen)
 	{
+		TheFramePacer->reset();
 		TheTransitionHandler->setGroup("FadeWholeScreen");
 		while(!TheTransitionHandler->isFinished())
 		{