sdl2: reuse window on mode change

src/sdl2/i_video.c

@@ -140,8 +140,8 @@ static       SDL_bool    videoblitok = SDL_FALSE;
 static       SDL_bool    exposevideo = SDL_FALSE;
 
 // SDL2 vars
-static SDL_Window   *window;
+SDL_Window   *window;
-static SDL_Renderer *renderer;
+SDL_Renderer *renderer;
 static SDL_Texture  *texture;
 static SDL_bool      havefocus = SDL_TRUE;
 
@@ -195,27 +195,37 @@ static void SDLSetMode(INT32 width, INT32 height, SDL_bool fullscreen)
 	int bmask;
 	int amask;
 
+	if (window)
+	{
 		if (fullscreen && !wasfullscreen)
 		{
 			// Recreate window in fullscreen
+			/*
 			   SDL_DestroyRenderer(renderer);
 			   renderer = NULL;
 			   SDL_DestroyWindow(window);
 			   window = NULL;
 			   Impl_CreateWindow(SDL_TRUE);
 			   Impl_SetWindowIcon();
+			   */
 			wasfullscreen = SDL_TRUE;
+			SDL_SetWindowFullscreen(window, SDL_WINDOW_FULLSCREEN_DESKTOP);
 		}
 		else if (!fullscreen && wasfullscreen)
 		{
 			// Recreate window in windowed mode
+			/*
 			   SDL_DestroyRenderer(renderer);
 			   renderer = NULL;
 			   SDL_DestroyWindow(window);
 			   window = NULL;
 			   Impl_CreateWindow(SDL_FALSE);
 			   Impl_SetWindowIcon();
+			   */
 			wasfullscreen = SDL_FALSE;
+			SDL_SetWindowFullscreen(window, 0);
+			SDL_SetWindowSize(window, width, height);
+			SDL_SetWindowPosition(window, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED);
 		}
 		else if (!wasfullscreen)
 		{
@@ -223,6 +233,13 @@ static void SDLSetMode(INT32 width, INT32 height, SDL_bool fullscreen)
 			SDL_SetWindowSize(window, width, height);
 			SDL_SetWindowPosition(window, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED);
 		}
+	}
+	else
+	{
+		Impl_CreateWindow(fullscreen ? SDL_TRUE : SDL_FALSE);
+		Impl_SetWindowIcon();
+		wasfullscreen = fullscreen ? SDL_TRUE : SDL_FALSE;
+	}
 
 	SDL_RenderSetLogicalSize(renderer, width, height);
 
@@ -1307,11 +1324,22 @@ void I_UpdateNoBlit(void)
 	if (!vidSurface)
 		return;
 	if (exposevideo)
+	{
+#ifdef HWRENDER
+		if (rendermode == render_opengl)
+		{
+			OglSdlFinishUpdate(cv_vidwait.value);
+			SDL_GL_SwapWindow(window);
+		}
+		else
+#endif
+		if (rendermode == render_soft)
 		{
 			SDL_RenderClear(renderer);
 			SDL_RenderCopy(renderer, texture, NULL, NULL);
 			SDL_RenderPresent(renderer);
 		}
+	}
 #if 0
 #ifdef HWRENDER
 	if (rendermode != render_soft)
@@ -1782,6 +1810,13 @@ static SDL_bool Impl_CreateWindow(SDL_bool fullscreen)
 		flags = SDL_WINDOW_FULLSCREEN_DESKTOP;
 	}
 
+#ifdef HWRENDER
+	if (rendermode == render_opengl)
+	{
+		flags |= SDL_WINDOW_OPENGL;
+	}
+#endif
+
 	window = SDL_CreateWindow("SRB2", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
 			realwidth, realheight, flags);
 	renderer = SDL_CreateRenderer(window, -1, 0);

src/sdl2/ogl_sdl.h

@@ -25,6 +25,9 @@ boolean OglSdlSurface(INT32 w, INT32 h, boolean isFullscreen);
 
 void OglSdlFinishUpdate(boolean vidwait);
 
+extern SDL_Window *window;
+extern SDL_Renderer *renderer;
+
 #ifdef _CREATE_DLL_
 EXPORT void HWRAPI( OglSdlSetPalette ) (RGBA_t *palette, RGBA_t *pgamma);
 #endif