SDL_CreateRGBSurface
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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] 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(3), SDL_FreeSurface(3), SDL_SetVideoMode(3), SDL_LockSurface(3), SDL_PixelFormat(3), SDL_Surface(3) SDL_SetAlpha(3) SDL_SetColorKey(3)

COPYRIGHT

This manual page is taken from the SDL library, licensed under GNU LGPL.
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