SDL_CreateRGBSurface(3) SDL API Reference SDL_CreateRGBSurface(3)

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

SDL Tue 11 Sep 2001, 23:01 SDL_CreateRGBSurface(3)