NAME¶

SDL_SetSurfaceAlphaMod - Set an additional alpha value used in blit operations.

SYNOPSIS¶

#include "SDL3/SDL.h"

int SDL_SetSurfaceAlphaMod(SDL_Surface *surface, Uint8 alpha);

DESCRIPTION¶

When this surface is blitted, during the blit operation the source alpha value is modulated by this alpha value according to the following formula: srcA=srcA*(alpha/255)

FUNCTION PARAMETERS¶

surface

the SDL_Surface
structure to update

alpha

the alpha value multiplied into blit operations

RETURN VALUE¶

Returns 0 on success or a negative error code on failure; call

SDL_GetError () for more information.

AVAILABILITY¶

This function is available since SDL 3.0.0.

SEE ALSO¶

SDL_GetSurfaceAlphaMod(3), SDL_SetSurfaceColorMod(3)