NAME
SDL_CreateRGBSurface - Create an empty SDL_Surface
SYNOPSIS
#include "SDL.h"
SDL_Surface *SDL_CreateRGBSurface(Uint32 flags, int width, int height,
int depth, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask);
DESCRIPTION
Allocate an empty surface (must be called after SDL_SetVideoMode)
If depth is 8 bits an empty palette is allocated for the surface,
otherwise a ’packed-pixel’ SDL_PixelFormat is created using the
[RGBA]mask’s provided (see SDL_PixelFormat). The flags specifies the
type of surface that should be created, it is an OR’d combination of
the following possible values.
SDL_SWSURFACE SDL will create the surface in system memory. This
improves the performance of pixel level access,
however you may not be able to take advantage of
some types of hardware blitting.
SDL_HWSURFACE SDL will attempt to create the surface in video
memory. This will allow SDL to take advantage of
Video->Video blits (which are often accelerated).
SDL_SRCCOLORKEY This flag turns on colourkeying for blits from this
surface. If SDL_HWSURFACE is also specified and
colourkeyed blits are hardware-accelerated, then
SDL will attempt to place the surface in video
memory. Use SDL_SetColorKey to set or clear this
flag after surface creation.
SDL_SRCALPHA This flag turns on alpha-blending for blits from
this surface. If SDL_HWSURFACE is also specified
and alpha-blending blits are hardware-accelerated,
then the surface will be placed in video memory if
possible. Use SDL_SetAlpha to set or clear this
flag after surface creation.
Note:
If an alpha-channel is specified (that is, if Amask is nonzero),
then the SDL_SRCALPHA flag is automatically set. You may remove
this flag by calling SDL_SetAlpha after surface creation.
RETURN VALUE
Returns the created surface, or NULL upon error.
EXAMPLE
/* 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
", SDL_GetError());
exit(1);
}
SEE ALSO
SDL_CreateRGBSurfaceFrom, SDL_FreeSurface, SDL_SetVideoMode,
SDL_LockSurface, SDL_PixelFormat, SDL_Surface SDL_SetAlpha
SDL_SetColorKey