Get the additional alpha value used in blit operations.
int SDL_GetSurfaceAlphaMod(SDL_Surface *surface, Uint8 *alpha);
|surface||the SDL_Surface structure to query|
|alpha||a pointer filled in with the current alpha value|
Returns 0 on success or a negative error code on failure; call SDL_GetError() for more information.
This function is available since SDL 3.0.0.