Set an additional alpha value multiplied into render copy operations.
int SDL_SetTextureAlphaMod(SDL_Texture * texture, Uint8 alpha);
|texture||the texture to update|
|alpha||the source alpha value multiplied into copy operations|
Returns 0 on success or a negative error code on failure; call SDL_GetError() for more information.
When this texture is rendered, during the copy operation the source alpha value is modulated by this alpha value according to the following formula:
srcA = srcA * (alpha / 255)
Alpha modulation is not always supported by the renderer; it will return -1 if alpha modulation is not supported.
This function is available since SDL 2.0.0.