SDL_SetColorKey(3) SDL API Reference SDL_SetColorKey(3)NAME
SDL_SetColorKey- Sets the color key (transparent pixel) in
a blittable surface and RLE acceleration.
SYNOPSIS
#include "SDL.h"
int SDL_SetColorKey(SDL_Surface *surface, Uint32 flag,
Uint32 key);
DESCRIPTION
Sets the color key (transparent pixel) in a blittable
surface and enables or disables RLE blit acceleration.
RLE acceleration can substantially speed up blitting of
images with large horizontal runs of transparent pixels
(i.e., pixels that match the key value). The key must be
of the same pixel format as the surface, SDL_MapRGB is
often useful for obtaining an acceptable value.
If flag is SDL_SRCCOLORKEY then key is the transparent
pixel value in the source image of a blit.
If flag is OR'd with SDL_RLEACCEL then the surface will be
draw using RLE acceleration when drawn with SDL_BlitSur-
face. The surface will actually be encoded for RLE accel-
eration the first time SDL_BlitSurface or SDL_DisplayFor-
mat is called on the surface.
If flag is 0, this function clears any current color key.
RETURN VALUE
This function returns 0, or -1 if there was an error.
SEE ALSO
SDL_BlitSurface, SDL_DisplayFormat, SDL_MapRGB, SDL_SetAl-
pha
SDL Tue 11 Sep 2001, 23:01 SDL_SetColorKey(3)
