| .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 |
