# SDL_SetSurfaceColorKey

Set the color key (transparent pixel) in a surface.

## Header File

Defined in [<SDL3/SDL_surface.h>](https://github.com/libsdl-org/SDL/blob/main/include/SDL3/SDL_surface.h)

## Syntax

```c
bool SDL_SetSurfaceColorKey(SDL_Surface *surface, bool enabled, Uint32 key);
```

## Function Parameters

|                              |             |                                                       |
| ---------------------------- | ----------- | ----------------------------------------------------- |
| [SDL_Surface](SDL_Surface) * | **surface** | the [SDL_Surface](SDL_Surface) structure to update.   |
| bool                         | **enabled** | true to enable color key, false to disable color key. |
| [Uint32](Uint32)             | **key**     | the transparent pixel.                                |

## Return Value

(bool) Returns true on success or false on failure; call
[SDL_GetError](SDL_GetError)() for more information.

## Remarks

The color key defines a pixel value that will be treated as transparent in
a blit. For example, one can use this to specify that cyan pixels should be
considered transparent, and therefore not rendered.

It is a pixel of the format used by the surface, as generated by
[SDL_MapRGB](SDL_MapRGB)().

## Thread Safety

This function is not thread safe.

## Version

This function is available since SDL 3.2.0.

## See Also

- [SDL_GetSurfaceColorKey](SDL_GetSurfaceColorKey)
- [SDL_SetSurfaceRLE](SDL_SetSurfaceRLE)
- [SDL_SurfaceHasColorKey](SDL_SurfaceHasColorKey)

----
[CategoryAPI](CategoryAPI), [CategoryAPIFunction](CategoryAPIFunction), [CategorySurface](CategorySurface)