SCI32: Fix video performance benchmarking in most SCI32 games

Most SCI32 games draw a "fred" object to the screen when the game
first starts to benchmark video performance. When framerate
throttling is enabled (which fixes many/most timing-related bugs
and reduces system load caused by unnecessary graphics updates),
the game's performance check will think that video card is slow,
causing some "high-performance" game features to be disabled.

To avoid this, we simply disable throttling during benchmarking by
detecting the "fred" object.

engines/sci/engine/kgraphics32.cpp

@@ -133,8 +133,6 @@ reg_t kGetHighPlanePri(EngineState *s, int argc, reg_t *argv) {
 reg_t kFrameOut(EngineState *s, int argc, reg_t *argv) {
 	bool showBits = argc > 0 ? argv[0].toUint16() : true;
 	g_sci->_gfxFrameout->kernelFrameOut(showBits);
-	s->speedThrottler(16);
-	s->_throttleTrigger = true;
 	return s->r_acc;
 }
 

engines/sci/graphics/frameout.cpp

@@ -77,6 +77,8 @@ GfxFrameout::GfxFrameout(SegManager *segMan, ResourceManager *resMan, GfxCoordAd
 	_screen(screen),
 	_segMan(segMan),
 	_paint32(paint32),
+	_benchmarkingFinished(false),
+	_throttleFrameOut(true),
 	_showStyles(nullptr),
 	// TODO: Stop using _gfxScreen
 	_currentBuffer(screen->getDisplayWidth(), screen->getDisplayHeight(), nullptr),
@@ -258,6 +260,17 @@ void GfxFrameout::syncWithScripts(bool addElements) {
 #pragma mark Screen items
 
 void GfxFrameout::kernelAddScreenItem(const reg_t object) {
+	// The "fred" object is used to test graphics performance;
+	// it is impacted by framerate throttling, so disable the
+	// throttling when this item is on the screen for the
+	// performance check to pass.
+	if (!_benchmarkingFinished && (
+		(int16)readSelectorValue(_segMan, object, SELECTOR(view)) == -556 ||
+		Common::String(_segMan->getObjectName(object)) == "fred"
+	)) {
+		_throttleFrameOut = false;
+	}
+
 	const reg_t planeObject = readSelector(_segMan, object, SELECTOR(plane));
 
 	_segMan->getObject(object)->setInfoSelectorFlag(kInfoFlagViewInserted);
@@ -297,6 +310,18 @@ void GfxFrameout::kernelUpdateScreenItem(const reg_t object) {
 }
 
 void GfxFrameout::kernelDeleteScreenItem(const reg_t object) {
+	// The "fred" object is used to test graphics performance;
+	// it is impacted by framerate throttling, so disable the
+	// throttling when this item is on the screen for the
+	// performance check to pass.
+	if (!_benchmarkingFinished && (
+		(int16)readSelectorValue(_segMan, object, SELECTOR(view)) == -556 ||
+		Common::String(_segMan->getObjectName(object)) == "fred"
+	)) {
+		_benchmarkingFinished = true;
+		_throttleFrameOut = true;
+	}
+
 	_segMan->getObject(object)->clearInfoSelectorFlag(kInfoFlagViewInserted);
 
 	const reg_t planeObject = readSelector(_segMan, object, SELECTOR(plane));
@@ -1395,6 +1420,11 @@ void GfxFrameout::kernelFrameOut(const bool shouldShowBits) {
 
 		frameOut(shouldShowBits);
 	}
+
+	if (_throttleFrameOut) {
+		g_sci->getEngineState()->speedThrottler(16);
+		g_sci->getEngineState()->_throttleTrigger = true;
+	}
 }
 
 #pragma mark -

engines/sci/graphics/frameout.h

@@ -178,6 +178,22 @@ class GfxFrameout {
 	void syncWithScripts(bool addElements); // this is what Game::restore does, only needed when our ScummVM dialogs are patched in
 	void run();
 
+#pragma mark -
+#pragma mark Benchmarking
+private:
+	/**
+	 * Optimization to avoid the more expensive object name
+	 * comparision on every call to kAddScreenItem and
+	 * kRemoveScreenItem.
+	 */
+	bool _benchmarkingFinished;
+
+	/**
+	 * Whether or not calls to kFrameOut should be framerate
+	 * limited to ~60fps.
+	 */
+	bool _throttleFrameOut;
+
 #pragma mark -
 #pragma mark Screen items
 private: