SDL: Add experimental support for SDL2.

This is based upon skristiansson's change set to make ScummVM work with SDL2.

1 files changed, 118 insertions, 16 deletions

diff --git a/backends/graphics/openglsdl/openglsdl-graphics.cpp b/backends/graphics/openglsdl/openglsdl-graphics.cpp
index fc2956755d..2710b66ecd 100644
--- a/backends/graphics/openglsdl/openglsdl-graphics.cpp
+++ b/backends/graphics/openglsdl/openglsdl-graphics.cpp
@@ -29,7 +29,12 @@
 #endif
 
 OpenGLSdlGraphicsManager::OpenGLSdlGraphicsManager(uint desktopWidth, uint desktopHeight, SdlEventSource *eventSource)
-    : SdlGraphicsManager(eventSource), _lastVideoModeLoad(0), _hwScreen(nullptr), _lastRequestedWidth(0), _lastRequestedHeight(0),
+    : SdlGraphicsManager(eventSource), _lastRequestedHeight(0),
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+      _glContext(),
+#else
+      _lastVideoModeLoad(0), _hwScreen(nullptr),
+#endif
       _graphicsScale(2), _ignoreLoadVideoMode(false), _gotResize(false), _wantsFullScreen(false), _ignoreResizeEvents(0),
       _desiredFullscreenWidth(0), _desiredFullscreenHeight(0) {
 	// Setup OpenGL attributes for SDL
@@ -40,6 +45,17 @@ OpenGLSdlGraphicsManager::OpenGLSdlGraphicsManager(uint desktopWidth, uint deskt
 	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
 
 	// Retrieve a list of working fullscreen modes
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+	const int numModes = SDL_GetNumDisplayModes(0);
+	for (int i = 0; i < numModes; ++i) {
+		SDL_DisplayMode mode;
+		if (SDL_GetDisplayMode(0, i, &mode)) {
+			continue;
+		}
+
+		_fullscreenVideoModes.push_back(VideoMode(mode.w, mode.h));
+	}
+#else
 	const SDL_Rect *const *availableModes = SDL_ListModes(NULL, SDL_OPENGL | SDL_FULLSCREEN);
 	if (availableModes != (void *)-1) {
 		for (;*availableModes; ++availableModes) {
@@ -47,9 +63,19 @@ OpenGLSdlGraphicsManager::OpenGLSdlGraphicsManager(uint desktopWidth, uint deskt
 
 			_fullscreenVideoModes.push_back(VideoMode(mode->w, mode->h));
 		}
+	}
+#endif
+
+	// Sort the modes in ascending order.
+	Common::sort(_fullscreenVideoModes.begin(), _fullscreenVideoModes.end());
 
-		// Sort the modes in ascending order.
-		Common::sort(_fullscreenVideoModes.begin(), _fullscreenVideoModes.end());
+	// Strip duplicates in video modes.
+	for (uint i = 0; i + 1 < _fullscreenVideoModes.size();) {
+		if (_fullscreenVideoModes[i] == _fullscreenVideoModes[i + 1]) {
+			_fullscreenVideoModes.remove_at(i);
+		} else {
+			++i;
+		}
 	}
 
 	// In case SDL is fine with every mode we will force the desktop mode.
@@ -120,11 +146,19 @@ void OpenGLSdlGraphicsManager::setFeatureState(OSystem::Feature f, bool enable)
 bool OpenGLSdlGraphicsManager::getFeatureState(OSystem::Feature f) {
 	switch (f) {
 	case OSystem::kFeatureFullscreenMode:
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+		if (_window) {
+			return (SDL_GetWindowFlags(_window) & SDL_WINDOW_FULLSCREEN) != 0;
+		} else {
+			return _wantsFullScreen;
+		}
+#else
 		if (_hwScreen) {
 			return (_hwScreen->flags & SDL_FULLSCREEN) != 0;
 		} else {
 			return _wantsFullScreen;
 		}
+#endif
 
 	default:
 		return OpenGLGraphicsManager::getFeatureState(f);
@@ -201,13 +235,20 @@ void OpenGLSdlGraphicsManager::updateScreen() {
 	OpenGLGraphicsManager::updateScreen();
 
 	// Swap OpenGL buffers
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+	SDL_GL_SwapWindow(_window);
+#else
 	SDL_GL_SwapBuffers();
+#endif
 }
 
 void OpenGLSdlGraphicsManager::notifyVideoExpose() {
 }
 
 void OpenGLSdlGraphicsManager::notifyResize(const uint width, const uint height) {
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+	setActualScreenSize(width, height);
+#else
 	if (!_ignoreResizeEvents && _hwScreen && !(_hwScreen->flags & SDL_FULLSCREEN)) {
 		// We save that we handled a resize event here. We need to know this
 		// so we do not overwrite the users requested window size whenever we
@@ -218,6 +259,7 @@ void OpenGLSdlGraphicsManager::notifyResize(const uint width, const uint height)
 			g_system->quit();
 		}
 	}
+#endif
 }
 
 void OpenGLSdlGraphicsManager::transformMouseCoordinates(Common::Point &point) {
@@ -300,6 +342,58 @@ bool OpenGLSdlGraphicsManager::setupMode(uint width, uint height) {
 		height = _desiredFullscreenHeight;
 	}
 
+	// This is pretty confusing since RGBA8888 talks about the memory
+	// layout here. This is a different logical layout depending on
+	// whether we run on little endian or big endian. However, we can
+	// only safely assume that RGBA8888 in memory layout is supported.
+	// Thus, we chose this one.
+	const Graphics::PixelFormat rgba8888 =
+#ifdef SCUMM_LITTLE_ENDIAN
+	                                       Graphics::PixelFormat(4, 8, 8, 8, 8, 0, 8, 16, 24);
+#else
+	                                       Graphics::PixelFormat(4, 8, 8, 8, 8, 24, 16, 8, 0);
+#endif
+
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+	if (_glContext) {
+		notifyContextDestroy();
+
+		SDL_GL_DeleteContext(_glContext);
+		_glContext = nullptr;
+	}
+
+	destroyWindow();
+
+	uint32 flags = SDL_WINDOW_OPENGL;
+	if (_wantsFullScreen) {
+		flags |= SDL_WINDOW_FULLSCREEN;
+	} else {
+		flags |= SDL_WINDOW_RESIZABLE;
+	}
+
+	if (!createWindow(width, height, flags)) {
+		// We treat fullscreen requests as a "hint" for now. This means in
+		// case it is not available we simply ignore it.
+		if (_wantsFullScreen) {
+			createWindow(width, height, SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE);
+		}
+
+		if (!_window) {
+			return false;
+		}
+	}
+
+	_glContext = SDL_GL_CreateContext(_window);
+	if (!_glContext) {
+		return false;
+	}
+
+	notifyContextCreate(rgba8888, rgba8888);
+	int actualWidth, actualHeight;
+	SDL_GetWindowSize(_window, &actualWidth, &actualHeight);
+	setActualScreenSize(actualWidth, actualHeight);
+	return true;
+#else
 	// WORKAROUND: Working around infamous SDL bugs when switching
 	// resolutions too fast. This might cause the event system to supply
 	// incorrect mouse position events otherwise.
@@ -341,17 +435,6 @@ bool OpenGLSdlGraphicsManager::setupMode(uint width, uint height) {
 	_lastVideoModeLoad = SDL_GetTicks();
 
 	if (_hwScreen) {
-		// This is pretty confusing since RGBA8888 talks about the memory
-		// layout here. This is a different logical layout depending on
-		// whether we run on little endian or big endian. However, we can
-		// only safely assume that RGBA8888 in memory layout is supported.
-		// Thus, we chose this one.
-		const Graphics::PixelFormat rgba8888 =
-#ifdef SCUMM_LITTLE_ENDIAN
-		                                       Graphics::PixelFormat(4, 8, 8, 8, 8, 0, 8, 16, 24);
-#else
-		                                       Graphics::PixelFormat(4, 8, 8, 8, 8, 24, 16, 8, 0);
-#endif
 		notifyContextCreate(rgba8888, rgba8888);
 		setActualScreenSize(_hwScreen->w, _hwScreen->h);
 	}
@@ -363,6 +446,21 @@ bool OpenGLSdlGraphicsManager::setupMode(uint width, uint height) {
 		_ignoreResizeEvents = 10;
 
 	return _hwScreen != nullptr;
+#endif
+}
+
+void OpenGLSdlGraphicsManager::getWindowDimensions(int *width, int *height) {
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+	SDL_GetWindowSize(_window, width, height);
+#else
+	if (width) {
+		*width = _hwScreen->w;
+	}
+
+	if (height) {
+		*height = _hwScreen->h;
+	}
+#endif
 }
 
 bool OpenGLSdlGraphicsManager::notifyEvent(const Common::Event &event) {
@@ -456,7 +554,9 @@ bool OpenGLSdlGraphicsManager::notifyEvent(const Common::Event &event) {
 					// Calculate the next scaling setting. We approximate the
 					// current scale setting in case the user resized the
 					// window. Then we apply the direction change.
-					_graphicsScale = MAX<int>(_hwScreen->w / _lastRequestedWidth, _hwScreen->h / _lastRequestedHeight);
+					int windowWidth = 0, windowHeight = 0;
+					getWindowDimensions(&windowWidth, &windowHeight);
+					_graphicsScale = MAX<int>(windowWidth / _lastRequestedWidth, windowHeight / _lastRequestedHeight);
 					_graphicsScale = MAX<int>(_graphicsScale + direction, 1);
 
 					// Since we overwrite a user resize here we reset its
@@ -472,7 +572,9 @@ bool OpenGLSdlGraphicsManager::notifyEvent(const Common::Event &event) {
 				}
 
 #ifdef USE_OSD
-				const Common::String osdMsg = Common::String::format("Resolution: %dx%d", _hwScreen->w, _hwScreen->h);
+				int windowWidth = 0, windowHeight = 0;
+				getWindowDimensions(&windowWidth, &windowHeight);
+				const Common::String osdMsg = Common::String::format("Resolution: %dx%d", windowWidth, windowHeight);
 				displayMessageOnOSD(osdMsg.c_str());
 #endif