SDL2 Invalid renderer on SDL_GetWindowSurface and/or SDL_CreateRenderer on OSX

问题

So I've been playing around with SDL2 to see if it would suit my needs. I was following introductory examples (from lazyfoo mostly) and made a simple test.

#include <stdio.h>
#include <SDL.h>

const int SCREEN_WIDTH = 640;
const int SCREEN_HEIGHT = 480;

int main(int argc, char const *argv[]) {

    /* The window handle */
    SDL_Window* window = NULL;

    /* The surface contained in the window */
    SDL_Surface* screen_surface = NULL;

    /* Init SDL */
    if(SDL_Init(SDL_INIT_VIDEO) < 0) {
        printf("SDL could not initialize! SDL Error: %s\n", SDL_GetError());
        return 1;
    }
    else {
        /* Create window */
        window = SDL_CreateWindow(
            "SDL Window", 
            SDL_WINDOWPOS_CENTERED, 
            SDL_WINDOWPOS_CENTERED, 
            SCREEN_WIDTH, 
            SCREEN_HEIGHT, 
            SDL_WINDOW_SHOWN | SDL_WINDOW_BORDERLESS
        );

        if(window == NULL) {
            printf("Window could not be created! SDL Error: %s\n", SDL_GetError());
            return 1;
        }
        else {
            // /* Get window surface */
            screen_surface = SDL_GetWindowSurface(window);

            // /* Fill the surface white */
            SDL_FillRect(screen_surface, NULL, SDL_MapRGB(screen_surface->format, 0x50, 0x50, 0x50));

            // /* Update the surface */
            SDL_UpdateWindowSurface(window);

            printf("%s\n", SDL_GetError());

            /* Wait n secs */
            SDL_Delay(2000);

        }
    }

    /* Destroy the window */
    SDL_DestroyWindow(window);

    /* Quit SDL subsystem */
    SDL_Quit();

    return 0;
}

Compiled on OSX 10.7.5 (MBA 2011) with:

gcc `sdl2-config --cflags --libs` -o sdl_test sdl_test.c

Example is simple enough. It should init SDL, create a window, attach a surface to the window, set the color to gray and render it out - after two seconds it should exit.

However, window stays black. No gray surface shown. That's why I introduced that printf for SDL errors before delay. It shows Invalid renderer which I have tracked down to be triggered by screen_surface = SDL_GetWindowSurface(window);

I have also tried to do it the other way with

renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_SOFTWARE);
SDL_SetRenderDrawColor(renderer, 255, 0, 0, 255);
SDL_RenderClear(renderer);
SDL_RenderPresent(renderer);

instead of SDL_Surface way.. but same thing happens Invalid renderer thrown out on SDL_CreateRenderer. As you can see, I tried it with _SOFTWARE and _ACCELERATED flags - same thing.

Now, here's the 'funny' part. In first code, with SDL_Surface way I have called SDL_UpdateWindowSurface(window); twice - one after the other. Gray color shows! However, Invalid renderer is still thrown out, but code works. Why would calling SDL_UpdateWindowSurface(window); twice, one after the other, work and once it wouldn't? Why would it work at all if Invalid renderer is thrown out? I'm deeply puzzled.

OSX: 10.7.5
compiler: i686-apple-darwin11-llvm-gcc-4.2 (GCC) 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.11.00)
SDL2: 2.0.3 (installed via homebrew)

I also tried invoking gcc without sdl2-config by manually typing include path and libs.

来源：https://stackoverflow.com/questions/25003676/sdl2-invalid-renderer-on-sdl-getwindowsurface-and-or-sdl-createrenderer-on-osx

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macos

sdl

sdl-2