.TH "SDL_SetPalette" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" 

.SH "NAME"

SDL_SetPalette \- Sets the colors in the palette of an 8-bit surface\&.

.SH "SYNOPSIS"

.PP

\fB#include "SDL\&.h"

.sp

\fBint \fBSDL_SetPalette\fP\fR(\fBSDL_Surface *surface, int flags, SDL_Color *colors, int firstcolor, int ncolors\fR);

.SH "DESCRIPTION"

.PP

Sets a portion of the palette for the given 8-bit surface\&.

.PP

Palettized (8-bit) screen surfaces with the \fBSDL_HWPALETTE\fP flag have two palettes, a logical palette that is used for mapping blits to/from the surface and a physical palette (that determines how the hardware will map the colors to the display)\&. \fISDL_BlitSurface\fR always uses the logical palette when blitting surfaces (if it has to convert between surface pixel formats)\&. Because of this, it is often useful to modify only one or the other palette to achieve various special color effects (e\&.g\&., screen fading, color flashes, screen dimming)\&.

.PP

This function can modify either the logical or physical palette by specifing \fBSDL_LOGPAL\fP or \fBSDL_PHYSPAL\fPthe in the \fBflags\fR parameter\&.

.PP

When \fBsurface\fR is the surface associated with the current display, the display colormap will be updated with the requested colors\&. If \fBSDL_HWPALETTE\fP was set in \fISDL_SetVideoMode\fR flags, \fBSDL_SetPalette\fP will always return \fB1\fR, and the palette is guaranteed to be set the way you desire, even if the window colormap has to be warped or run under emulation\&.

.PP

The color components of a \fI\fBSDL_Color\fR\fR structure are 8-bits in size, giving you a total of 256^3=16777216 colors\&.

.SH "RETURN VALUE"

.PP

If \fBsurface\fR is not a palettized surface, this function does nothing, returning \fB0\fR\&. If all of the colors were set as passed to \fBSDL_SetPalette\fP, it will return \fB1\fR\&. If not all the color entries were set exactly as given, it will return \fB0\fR, and you should look at the surface palette to determine the actual color palette\&.

.SH "EXAMPLE"

.PP

.nf

\f(CW        /* Create a display surface with a grayscale palette */

        SDL_Surface *screen;

        SDL_Color colors[256];

        int i;

        \&.

        \&.

        \&.

        /* Fill colors with color information */

        for(i=0;i<256;i++){

          colors[i]\&.r=i;

          colors[i]\&.g=i;

          colors[i]\&.b=i;

        }

        /* Create display */

        screen=SDL_SetVideoMode(640, 480, 8, SDL_HWPALETTE);

        if(!screen){

          printf("Couldn\&'t set video mode: %s

", SDL_GetError());

          exit(-1);

        }

        /* Set palette */

        SDL_SetPalette(screen, SDL_LOGPAL|SDL_PHYSPAL, colors, 0, 256);

        \&.

        \&.

        \&.

        \&.\fR

.fi

.PP

.SH "SEE ALSO"

.PP

\fISDL_SetColors\fR, \fISDL_SetVideoMode\fR, \fISDL_Surface\fR, \fISDL_Color\fR

...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01