Wiki Page Content


Use this function to allocate a new RGB surface.


SDL_Surface* SDL_CreateRGBSurface(Uint32 flags,
                                  int    width,
                                  int    height,
                                  int    depth,
                                  Uint32 Rmask,
                                  Uint32 Gmask,
                                  Uint32 Bmask,
                                  Uint32 Amask)

Function Parameters


the flags are unused and should be set to 0


the width of the surface


the height of the surface


the depth of the surface in bits; see Remarks for details


the red mask for the pixels


the green mask for the pixels


the blue mask for the pixels


the alpha mask for the pixels

Return Value

Returns the new SDL_Surface structure that is created or NULL if it fails; call SDL_GetError() for more information.

Code Examples

    /* 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 */
    rmask = 0xff000000;
    gmask = 0x00ff0000;
    bmask = 0x0000ff00;
    amask = 0x000000ff;
    rmask = 0x000000ff;
    gmask = 0x0000ff00;
    bmask = 0x00ff0000;
    amask = 0xff000000;

    surface = SDL_CreateRGBSurface(0, width, height, 32,
                                   rmask, gmask, bmask, amask);
    if (surface == NULL) {
        SDL_Log("SDL_CreateRGBSurface() failed: %s", SDL_GetError());

    /* or using the default masks for the depth: */
    surface = SDL_CreateRGBSurface(0, width, height, 32, 0, 0, 0, 0);


If depth is 4 or 8 bits, an empty palette is allocated for the surface. If depth is greater than 8 bits, the pixel format is set using the [RGBA]mask parameters.

The [RGBA]mask parameters are the bitmasks used to extract that color from a pixel. For instance, Rmask being FF000000 means the red data is stored in the most significant byte. Using zeros for the RGB masks sets a default value, based on the depth. (e.g. SDL_CreateRGBSurface(0,w,h,32,0,0,0,0);) However, using zero for the Amask results in an Amask of 0.

By default surfaces with an alpha mask are set up for blending as with

  • SDL_SetSurfaceBlendMode(surface, SDL_BLENDMODE_BLEND)

You can change this by calling SDL_SetSurfaceBlendMode() and selecting a different blendMode.

CategoryAPI, CategorySurface

None: SDL_CreateRGBSurface (last edited 2016-10-20 20:36:00 by PhilippWiesemann)

Please include your contact information if you'd like to receive a reply.