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>SDL Library Documentation<
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NAME="SDLSETCOLORKEY"
CLASS="REFNAMEDIV"
NAME="AEN1630"
>SDL_SetColorKey -- Sets the color key (transparent pixel) in a blittable surface and
CLASS="REFSYNOPSISDIV"
NAME="AEN1633"
CLASS="FUNCSYNOPSIS"
NAME="AEN1634"
CLASS="FUNCSYNOPSISINFO"
CLASS="FUNCDEF"
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>
(SDL_Surface *surface, Uint32 flag, Uint32 key
);<
/CODE
CLASS="REFSECT1"
NAME="AEN1640"
> Sets the color key (transparent pixel) in a blittable surface and enables or
disables RLE blit acceleration.<
/P
>RLE acceleration can substantially speed up blitting of images with large
horizontal runs of transparent pixels (i.e., pixels that match the
CLASS="PARAMETER"
CLASS="PARAMETER"
> must be of the same pixel format as the <
TT
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HREF="sdlmaprgb.html"
CLASS="FUNCTION"
> is often useful
for obtaining an acceptable
value.<
/P
CLASS="PARAMETER"
CLASS="LITERAL"
> then
CLASS="PARAMETER"
> is the transparent pixel value in the source image of a
CLASS="PARAMETER"
> is OR'd with
<TT
CLASS="LITERAL"
>SDL_RLEACCEL</TT
> then the surface will be draw using RLE
acceleration when drawn with
<A
HREF="sdlblitsurface.html"
>SDL_BlitSurface</A
>. The surface will
actually be encoded for RLE acceleration the first time
<A
HREF="sdlblitsurface.html"
>SDL_BlitSurface</A
> or
<A
HREF="sdldisplayformat.html"
>SDL_DisplayFormat</A
> is called on the
surface.</P
><P
>If <TT
CLASS="PARAMETER"
><I
>flag</I
></TT
> is 0, this function clears
any current color key.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1661"
></A
><H2
>Return Value</H2
><P
>This function returns <SPAN
CLASS="RETURNVALUE"
>0</SPAN
>, or
<SPAN
CLASS="RETURNVALUE"
>-1</SPAN
> if there was an error.</P
></DIV
><DIV
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><A
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></A
><H2
>See Also</H2
><P
><A
HREF="sdlblitsurface.html"
><TT
CLASS="FUNCTION"
>SDL_BlitSurface</TT
></A
>,
<A
HREF="sdldisplayformat.html"
><TT
CLASS="FUNCTION"
>SDL_DisplayFormat</TT
></A
>,
<A
HREF="sdlmaprgb.html"
><TT
CLASS="FUNCTION"
>SDL_MapRGB</TT
></A
>,
<A
HREF="sdlsetalpha.html"
><TT
CLASS="FUNCTION"
>SDL_SetAlpha</TT
></A
></P
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