SDL_CreateRGBSurfaceFrom
Use this function to allocate a new RGB surface with existing pixel data.
Syntax
SDL_Surface* SDL_CreateRGBSurfaceFrom (void* pixels,
int width,
int height,
int depth,
int pitch,
Uint32 Rmask,
Uint32 Gmask,
Uint32 Bmask,
Uint32 Amask)
Function Parameters
pixels |
a pointer to existing pixel data |
width |
the width of the surface |
height |
the height of the surface |
depth |
the depth of the surface in bits; see Remarks for details |
pitch |
the length of a row of pixels in bytes |
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 the new SDL_Surface structure that is created or NULL if it fails; call SDL_GetError() for more information.
Code Examples
You can add your code example here
Remarks
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.
No copy is made of the pixel data. Pixel data is not managed automatically; you must free the surface before you free the pixel data.