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| Use this function to allocate ,,and free,, an RGB surface. | Use this function to allocate and free an RGB surface. |
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| <<Color2(green,There is a lot of extra info in the old wiki but most relates to '''flags'''. Should any of it be transferred here?)>> | <<Color2(green,There is a lot of extra info in the old wiki but most relates to '''flags'''. Should any of it be transferred here? http://www.libsdl.org/cgi/docwiki.cgi/SDL_CreateRGBSurface)>> |
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SDL_CreateRGBSurface
Use this function to allocate and free an RGB surface.
Contents
Syntax
SDL_Surface* SDL_CreateRGBSurface (Uint32 flags,
int width,
int height,
int depth,
Uint32 Rmask,
Uint32 Gmask,
Uint32 Bmask,
Uint32 Amask)
Function Parameters
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flags |
the flags are obsolete and should be set to 0 |
width |
the width of the surface |
height |
the height of the surface |
depth |
the depth of the surface in bits; see Remarks for details |
Rmask |
the red mask for the pixels |
Gmask |
the green mask for the pixels |
Bmask |
the blue mask for the pixels |
Amask |
the alpha mask for the pixels |
Return Value
Returns a pointer to an SDL_Surface to be created. If the function runs out of memory, it will return NULL.
Code Examples
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/* Create a 32-bit surface with the bytes of each pixel in R,G,B,A order,
as expected by OpenGL for textures */
SDL_Surface *surface;
Uint32 rmask, gmask, bmask, amask;
/* SDL interprets each pixel as a 32-bit number, so our masks must depend
on the endianness (byte order) of the machine */
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
rmask = 0xff000000;
gmask = 0x00ff0000;
bmask = 0x0000ff00;
amask = 0x000000ff;
#else
rmask = 0x000000ff;
gmask = 0x0000ff00;
bmask = 0x00ff0000;
amask = 0xff000000;
#endif
surface = SDL_CreateRGBSurface(SDL_SWSURFACE, width, height, 32,
rmask, gmask, bmask, amask);
if(surface == NULL) {
fprintf(stderr, "CreateRGBSurface failed: %s\n", SDL_GetError());
exit(1);
}
/* or using the default masks for the depth: */
surface=SDL_CreateRGBSurface(SDL_SWSURFACE,width,height,32,0,0,0,0);
Remarks
If the depth is 4 or 8 bits, an empty palette is allocated for the surface. If the depth is greater than 8 bits, the pixel format is set using the flags '[RGB]mask'.
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