SDL: Cleanup graphics manager switching a bit.

3 files changed, 68 insertions, 30 deletions

diff --git a/backends/graphics/sdl/sdl-graphics.cpp b/backends/graphics/sdl/sdl-graphics.cpp
index d42c88f5d6..58253c9509 100644
--- a/backends/graphics/sdl/sdl-graphics.cpp
+++ b/backends/graphics/sdl/sdl-graphics.cpp
@@ -69,3 +69,36 @@ void SdlGraphicsManager::warpMouseInWindow(uint x, uint y) {
 void SdlGraphicsManager::iconifyWindow() {
 	SDL_WM_IconifyWindow();
 }
+
+SdlGraphicsManager::State SdlGraphicsManager::getState() {
+	State state;
+
+	state.screenWidth   = getWidth();
+	state.screenHeight  = getHeight();
+	state.aspectRatio   = getFeatureState(OSystem::kFeatureAspectRatioCorrection);
+	state.fullscreen    = getFeatureState(OSystem::kFeatureFullscreenMode);
+	state.cursorPalette = getFeatureState(OSystem::kFeatureCursorPalette);
+#ifdef USE_RGB_COLOR
+	state.pixelFormat   = getScreenFormat();
+#endif
+
+	return state;
+}
+
+bool SdlGraphicsManager::setState(const State &state) {
+	beginGFXTransaction();
+#ifdef USE_RGB_COLOR
+		initSize(state.screenWidth, state.screenHeight, &state.pixelFormat);
+#else
+		initSize(state.screenWidth, state.screenHeight, 0);
+#endif
+		setFeatureState(OSystem::kFeatureAspectRatioCorrection, state.aspectRatio);
+		setFeatureState(OSystem::kFeatureFullscreenMode, state.fullscreen);
+		setFeatureState(OSystem::kFeatureCursorPalette, state.cursorPalette);
+
+	if (endGFXTransaction() != OSystem::kTransactionSuccess) {
+		return false;
+	} else {
+		return true;
+	}
+}
diff --git a/backends/graphics/sdl/sdl-graphics.h b/backends/graphics/sdl/sdl-graphics.h
index 216fc2d200..3a53a4e40e 100644
--- a/backends/graphics/sdl/sdl-graphics.h
+++ b/backends/graphics/sdl/sdl-graphics.h
@@ -129,6 +129,31 @@ public:
 	 */
 	void iconifyWindow();
 
+	/**
+	 * A (subset) of the graphic manager's state. This is used when switching
+	 * between different SDL graphic managers on runtime.
+	 */
+	struct State {
+		int screenWidth, screenHeight;
+		bool aspectRatio;
+		bool fullscreen;
+		bool cursorPalette;
+
+#ifdef USE_RGB_COLOR
+		Graphics::PixelFormat pixelFormat;
+#endif
+	};
+
+	/**
+	 * Queries the current state of the graphic manager.
+	 */
+	State getState();
+
+	/**
+	 * Setup a basic state of the graphic manager.
+	 */
+	bool setState(const State &state);
+
 protected:
 	SdlEventSource *_eventSource;
 };
diff --git a/backends/platform/sdl/sdl.cpp b/backends/platform/sdl/sdl.cpp
index 6a2643b048..d3a6e5e658 100644
--- a/backends/platform/sdl/sdl.cpp
+++ b/backends/platform/sdl/sdl.cpp
@@ -571,14 +571,8 @@ bool OSystem_SDL::setGraphicsMode(int mode) {
 	//
 	// This is a probably temporary workaround to fix bugs like #3368143
 	// "SDL/OpenGL: Crash when switching renderer backend".
-	const int screenWidth = _graphicsManager->getWidth();
-	const int screenHeight = _graphicsManager->getHeight();
-	const bool arState = _graphicsManager->getFeatureState(kFeatureAspectRatioCorrection);
-	const bool fullscreen = _graphicsManager->getFeatureState(kFeatureFullscreenMode);
-	const bool cursorPalette = _graphicsManager->getFeatureState(kFeatureCursorPalette);
-#ifdef USE_RGB_COLOR
-	const Graphics::PixelFormat pixelFormat = _graphicsManager->getScreenFormat();
-#endif
+	SdlGraphicsManager *sdlGraphicsManager = dynamic_cast<SdlGraphicsManager *>(_graphicsManager);
+	SdlGraphicsManager::State state = sdlGraphicsManager->getState();
 
 	bool switchedManager = false;
 
@@ -586,16 +580,16 @@ bool OSystem_SDL::setGraphicsMode(int mode) {
 	// manager, delete and create the new mode graphics manager
 	if (_graphicsMode >= _firstGLMode && mode < _firstGLMode) {
 		debug(1, "switching to plain SDL graphics");
-		dynamic_cast<SdlGraphicsManager *>(_graphicsManager)->deactivateManager();
+		sdlGraphicsManager->deactivateManager();
 		delete _graphicsManager;
-		_graphicsManager = new SurfaceSdlGraphicsManager(_eventSource);
+		_graphicsManager = sdlGraphicsManager = new SurfaceSdlGraphicsManager(_eventSource);
 
 		switchedManager = true;
 	} else if (_graphicsMode < _firstGLMode && mode >= _firstGLMode) {
 		debug(1, "switching to OpenGL graphics");
-		dynamic_cast<SdlGraphicsManager *>(_graphicsManager)->deactivateManager();
+		sdlGraphicsManager->deactivateManager();
 		delete _graphicsManager;
-		_graphicsManager = new OpenGLSdlGraphicsManager(_desktopWidth, _desktopHeight, _eventSource);
+		_graphicsManager = sdlGraphicsManager = new OpenGLSdlGraphicsManager(_desktopWidth, _desktopHeight, _eventSource);
 
 		switchedManager = true;
 	}
@@ -603,24 +597,10 @@ bool OSystem_SDL::setGraphicsMode(int mode) {
 	_graphicsMode = mode;
 
 	if (switchedManager) {
-		dynamic_cast<SdlGraphicsManager *>(_graphicsManager)->activateManager();
-
-		_graphicsManager->beginGFXTransaction();
-#ifdef USE_RGB_COLOR
-		_graphicsManager->initSize(screenWidth, screenHeight, &pixelFormat);
-#else
-		_graphicsManager->initSize(screenWidth, screenHeight, 0);
-#endif
-		_graphicsManager->setFeatureState(kFeatureAspectRatioCorrection, arState);
-		_graphicsManager->setFeatureState(kFeatureFullscreenMode, fullscreen);
-		_graphicsManager->setFeatureState(kFeatureCursorPalette, cursorPalette);
-
-		// Worst part about this right now, tell the cursor manager to
-		// resetup the cursor + cursor palette if necessarily
+		sdlGraphicsManager->activateManager();
 
-		// First we need to try to setup the old state on the new manager...
-		if (_graphicsManager->endGFXTransaction() != kTransactionSuccess) {
-			// Oh my god if this failed the client code might just explode.
+		// This failing will probably have bad consequences...
+		if (!sdlGraphicsManager->setState(state)) {
 			return false;
 		}
 
@@ -629,7 +609,7 @@ bool OSystem_SDL::setGraphicsMode(int mode) {
 		CursorMan.popCursor();
 
 		// Next setup cursor palette if needed
-		if (cursorPalette) {
+		if (_graphicsManager->getFeatureState(kFeatureCursorPalette)) {
 			CursorMan.pushCursorPalette(0, 0, 0);
 			CursorMan.popCursorPalette();
 		}