+ For convenience, it seems to be a good idea to create this symbolic
+ buffer 'window' at the same size as the SDL backbuffer. Although it
+ should never be drawn to directly, it would do no harm nevertheless. */
+
+ // create additional (symbolic) buffer for double-buffering
+ ReCreateBitmap(&window, video.width, video.height);
+
+ // create dummy drawing buffer for headless mode, if needed
+ if (program.headless)
+ ReCreateBitmap(&backbuffer, video.width, video.height);
+}
+
+void SDLInitVideoBuffer(boolean fullscreen)
+{
+ SDLInitVideoBuffer_VideoBuffer(fullscreen);
+ SDLInitVideoBuffer_DrawBuffer();
+}
+
+static boolean SDLCreateScreen(boolean fullscreen)
+{
+ SDL_Surface *new_surface = NULL;
+
+ int surface_flags_window = SURFACE_FLAGS;
+ int surface_flags_fullscreen = SURFACE_FLAGS | SDL_WINDOW_FULLSCREEN_DESKTOP;
+
+#if 1
+ int renderer_flags = SDL_RENDERER_ACCELERATED | SDL_RENDERER_TARGETTEXTURE;
+#else
+ /* If SDL_CreateRenderer() is called from within a VirtualBox Windows VM
+ _without_ enabling 2D/3D acceleration and/or guest additions installed,
+ it will crash if flags are *not* set to SDL_RENDERER_SOFTWARE (because
+ it will try to use accelerated graphics and apparently fails miserably) */
+ int renderer_flags = SDL_RENDERER_SOFTWARE;
+#endif
+
+ int width = video.width;
+ int height = video.height;
+ int screen_width = video.screen_width;
+ int screen_height = video.screen_height;
+ int surface_flags = (fullscreen ? surface_flags_fullscreen :
+ surface_flags_window);
+
+ // default window size is unscaled
+ video.window_width = screen_width;
+ video.window_height = screen_height;
+
+ // store if initial screen mode is fullscreen mode when changing screen size
+ video.fullscreen_initial = fullscreen;
+
+ float window_scaling_factor = (float)setup.window_scaling_percent / 100;
+
+ video.window_width = window_scaling_factor * screen_width;
+ video.window_height = window_scaling_factor * screen_height;
+
+ if (sdl_texture_stream)
+ {
+ SDL_DestroyTexture(sdl_texture_stream);
+ sdl_texture_stream = NULL;
+ }
+
+ if (sdl_texture_target)
+ {
+ SDL_DestroyTexture(sdl_texture_target);
+ sdl_texture_target = NULL;
+ }
+
+ if (!(fullscreen && fullscreen_enabled))
+ {
+ if (sdl_renderer)
+ {
+ SDL_DestroyRenderer(sdl_renderer);
+ sdl_renderer = NULL;
+ }
+
+ if (sdl_window)
+ {
+ SDL_DestroyWindow(sdl_window);
+ sdl_window = NULL;
+ }
+ }
+
+ if (sdl_window == NULL)
+ sdl_window = SDL_CreateWindow(program.window_title,
+ SDL_WINDOWPOS_CENTERED,
+ SDL_WINDOWPOS_CENTERED,
+ video.window_width,
+ video.window_height,
+ surface_flags);
+
+ if (sdl_window != NULL)
+ {
+ if (sdl_renderer == NULL)
+ sdl_renderer = SDL_CreateRenderer(sdl_window, -1, renderer_flags);
+
+ if (sdl_renderer != NULL)
+ {
+ // SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, "linear");
+ SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, setup.window_scaling_quality);
+
+ SDLSetScreenVsyncMode(setup.vsync_mode);
+
+ sdl_texture_stream = SDL_CreateTexture(sdl_renderer,
+ SDL_PIXELFORMAT_ARGB8888,
+ SDL_TEXTUREACCESS_STREAMING,
+ width, height);
+
+ if (SDL_RenderTargetSupported(sdl_renderer))
+ sdl_texture_target = SDL_CreateTexture(sdl_renderer,
+ SDL_PIXELFORMAT_ARGB8888,
+ SDL_TEXTUREACCESS_TARGET,
+ width, height);
+
+ if (sdl_texture_stream != NULL)
+ {
+ // use SDL default values for RGB masks and no alpha channel
+ new_surface = SDL_CreateRGBSurface(0, width, height, 32, 0,0,0, 0);
+
+ if (new_surface == NULL)
+ Error(ERR_WARN, "SDL_CreateRGBSurface() failed: %s", SDL_GetError());
+ }
+ else
+ {
+ Error(ERR_WARN, "SDL_CreateTexture() failed: %s", SDL_GetError());
+ }
+ }
+ else
+ {
+ Error(ERR_WARN, "SDL_CreateRenderer() failed: %s", SDL_GetError());
+ }
+ }
+ else
+ {
+ Error(ERR_WARN, "SDL_CreateWindow() failed: %s", SDL_GetError());
+ }
+
+ SDLSetScreenProperties();
+
+ // store fullscreen state ("video.fullscreen_enabled" may not reflect this!)
+ if (new_surface != NULL)
+ fullscreen_enabled = fullscreen;
+
+ if (backbuffer == NULL)
+ backbuffer = CreateBitmapStruct();
+
+ backbuffer->width = video.width;
+ backbuffer->height = video.height;
+
+ if (backbuffer->surface)
+ SDL_FreeSurface(backbuffer->surface);
+
+ backbuffer->surface = new_surface;
+
+ return (new_surface != NULL);
+}
+
+boolean SDLSetVideoMode(boolean fullscreen)
+{
+ boolean success = FALSE;
+
+ SetWindowTitle();
+
+ if (fullscreen && !video.fullscreen_enabled && video.fullscreen_available)
+ {
+ // switch display to fullscreen mode, if available
+ success = SDLCreateScreen(TRUE);
+
+ if (!success)
+ {
+ // switching display to fullscreen mode failed -- do not try it again
+ video.fullscreen_available = FALSE;
+ }
+ else
+ {
+ video.fullscreen_enabled = TRUE;
+ }
+ }
+
+ if ((!fullscreen && video.fullscreen_enabled) || !success)
+ {
+ // switch display to window mode
+ success = SDLCreateScreen(FALSE);
+
+ if (!success)
+ {
+ // switching display to window mode failed -- should not happen
+ }
+ else
+ {
+ video.fullscreen_enabled = FALSE;
+ video.window_scaling_percent = setup.window_scaling_percent;
+ video.window_scaling_quality = setup.window_scaling_quality;
+
+ SDLSetScreenRenderingMode(setup.screen_rendering_mode);
+ }
+ }
+
+ SDLRedrawWindow(); // map window
+
+ return success;
+}
+
+void SDLSetWindowTitle(void)
+{
+ if (sdl_window == NULL)
+ return;
+
+ SDL_SetWindowTitle(sdl_window, program.window_title);
+}
+
+void SDLSetWindowScaling(int window_scaling_percent)
+{
+ if (sdl_window == NULL)
+ return;
+
+ float window_scaling_factor = (float)window_scaling_percent / 100;
+ int new_window_width = (int)(window_scaling_factor * video.screen_width);
+ int new_window_height = (int)(window_scaling_factor * video.screen_height);
+
+ SDL_SetWindowSize(sdl_window, new_window_width, new_window_height);
+
+ video.window_scaling_percent = window_scaling_percent;
+ video.window_width = new_window_width;
+ video.window_height = new_window_height;
+
+ SetWindowTitle();
+}
+
+void SDLSetWindowScalingQuality(char *window_scaling_quality)
+{
+ SDL_Texture *new_texture;
+
+ if (sdl_texture_stream == NULL)
+ return;
+
+ SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, window_scaling_quality);
+
+ new_texture = SDL_CreateTexture(sdl_renderer,
+ SDL_PIXELFORMAT_ARGB8888,
+ SDL_TEXTUREACCESS_STREAMING,
+ video.width, video.height);
+
+ if (new_texture != NULL)
+ {
+ SDL_DestroyTexture(sdl_texture_stream);
+
+ sdl_texture_stream = new_texture;
+ }
+
+ if (SDL_RenderTargetSupported(sdl_renderer))
+ new_texture = SDL_CreateTexture(sdl_renderer,
+ SDL_PIXELFORMAT_ARGB8888,
+ SDL_TEXTUREACCESS_TARGET,
+ video.width, video.height);
+ else
+ new_texture = NULL;
+
+ if (new_texture != NULL)
+ {
+ SDL_DestroyTexture(sdl_texture_target);
+
+ sdl_texture_target = new_texture;
+ }
+
+ SDLRedrawWindow();
+
+ video.window_scaling_quality = window_scaling_quality;
+}
+
+void SDLSetWindowFullscreen(boolean fullscreen)
+{
+ if (sdl_window == NULL)
+ return;
+
+ int flags = (fullscreen ? SDL_WINDOW_FULLSCREEN_DESKTOP : 0);
+
+ if (SDL_SetWindowFullscreen(sdl_window, flags) == 0)
+ video.fullscreen_enabled = fullscreen_enabled = fullscreen;
+
+ // if screen size was changed in fullscreen mode, correct desktop window size
+ if (!fullscreen && video.fullscreen_initial)
+ {
+ SDLSetWindowScaling(setup.window_scaling_percent);
+ SDL_SetWindowPosition(sdl_window,
+ SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED);
+
+ video.fullscreen_initial = FALSE;
+ }
+}
+
+void SDLSetDisplaySize(void)
+{
+ if (sdl_renderer != NULL)
+ {
+ int w, h;
+
+ SDL_GetRendererOutputSize(sdl_renderer, &w, &h);
+
+ video.display_width = w;
+ video.display_height = h;
+
+#if 0
+ Error(ERR_DEBUG, "SDL renderer size: %d x %d",
+ video.display_width, video.display_height);
+#endif
+ }
+ else
+ {
+ SDL_Rect display_bounds;
+
+ SDL_GetDisplayBounds(0, &display_bounds);