SDL: Support resizing the window when using the SDL1 GL renderer

src/platform/sdl/gl-common.c

@@ -51,9 +51,9 @@ void mSDLGLCommonInit(struct mSDLRenderer* renderer) {
 #else
 	SDL_GL_SetAttribute(SDL_GL_SWAP_CONTROL, 1);
 #ifdef COLOR_16_BIT
-	SDL_SetVideoMode(renderer->viewportWidth, renderer->viewportHeight, 16, SDL_OPENGL | (SDL_FULLSCREEN * renderer->fullscreen));
+	SDL_SetVideoMode(renderer->viewportWidth, renderer->viewportHeight, 16, SDL_OPENGL | SDL_RESIZABLE | (SDL_FULLSCREEN * renderer->fullscreen));
 #else
-	SDL_SetVideoMode(renderer->viewportWidth, renderer->viewportHeight, 32, SDL_OPENGL | (SDL_FULLSCREEN * renderer->fullscreen));
+	SDL_SetVideoMode(renderer->viewportWidth, renderer->viewportHeight, 32, SDL_OPENGL | SDL_RESIZABLE | (SDL_FULLSCREEN * renderer->fullscreen));
 #endif
 	SDL_WM_SetCaption(projectName, "");
 #endif

src/platform/sdl/gl-sdl.c

@@ -52,14 +52,18 @@ void mSDLGLRunloop(struct mSDLRenderer* renderer, void* user) {
 	while (mCoreThreadIsActive(context)) {
 		while (SDL_PollEvent(&event)) {
 			mSDLHandleEvent(context, &renderer->player, &event);
-#if SDL_VERSION_ATLEAST(2, 0, 0)
 			// Event handling can change the size of the screen
 			if (renderer->player.windowUpdated) {
+#if SDL_VERSION_ATLEAST(2, 0, 0)
 				SDL_GetWindowSize(renderer->window, &renderer->viewportWidth, &renderer->viewportHeight);
+#else
+				renderer->viewportWidth = renderer->player.newWidth;
+				renderer->viewportHeight = renderer->player.newHeight;
+				mSDLGLCommonInit(renderer);
+#endif
 				mSDLGLDoViewport(renderer->viewportWidth, renderer->viewportHeight, v);
 				renderer->player.windowUpdated = 0;
 			}
-#endif
 		}
 		renderer->core->desiredVideoDimensions(renderer->core, &renderer->width, &renderer->height);
 		if (renderer->width != v->width || renderer->height != v->height) {

src/platform/sdl/gles2-sdl.c

@@ -128,14 +128,18 @@ void mSDLGLES2Runloop(struct mSDLRenderer* renderer, void* user) {
 	while (mCoreThreadIsActive(context)) {
 		while (SDL_PollEvent(&event)) {
 			mSDLHandleEvent(context, &renderer->player, &event);
-#if SDL_VERSION_ATLEAST(2, 0, 0)
 			// Event handling can change the size of the screen
 			if (renderer->player.windowUpdated) {
+#if SDL_VERSION_ATLEAST(2, 0, 0)
 				SDL_GetWindowSize(renderer->window, &renderer->viewportWidth, &renderer->viewportHeight);
+#else
+				renderer->viewportWidth = renderer->player.newWidth;
+				renderer->viewportHeight = renderer->player.newHeight;
+				mSDLGLCommonInit(renderer);
+#endif
 				mSDLGLDoViewport(renderer->viewportWidth, renderer->viewportHeight, v);
 				renderer->player.windowUpdated = 0;
 			}
-#endif
 		}
 
 		if (mCoreSyncWaitFrameStart(&context->impl->sync)) {

src/platform/sdl/sdl-events.c

@@ -601,6 +601,12 @@ void mSDLHandleEvent(struct mCoreThread* context, struct mSDLPlayer* sdlContext,
 	case SDL_WINDOWEVENT:
 		_mSDLHandleWindowEvent(sdlContext, &event->window);
 		break;
+#else
+	case SDL_VIDEORESIZE:
+		sdlContext->newWidth = event->resize.w;
+		sdlContext->newHeight = event->resize.h;
+		sdlContext->windowUpdated = 1;
+		break;
 #endif
 	case SDL_KEYDOWN:
 	case SDL_KEYUP:

src/platform/sdl/sdl-events.h

@@ -63,10 +63,10 @@ struct mSDLPlayer {
 	size_t playerId;
 	struct mInputMap* bindings;
 	struct SDL_JoystickCombo* joystick;
+	int windowUpdated;
 #if SDL_VERSION_ATLEAST(2, 0, 0)
 	SDL_Window* window;
 	int fullscreen;
-	int windowUpdated;
 
 	struct mSDLRumble {
 		struct mRumble d;
@@ -76,6 +76,9 @@ struct mSDLPlayer {
 		float activeLevel;
 		struct CircleBuffer history;
 	} rumble;
+#else
+	int newWidth;
+	int newHeight;
 #endif
 
 	struct mSDLRotation {