| .TH "SDL_SetColors" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" |
| .SH "NAME" |
| SDL_SetColors \- Sets a portion of the colormap for the given 8-bit surface\&. |
| .SH "SYNOPSIS" |
| .PP |
| \fB#include "SDL\&.h" |
| .sp |
| \fBint \fBSDL_SetColors\fP\fR(\fBSDL_Surface *surface, SDL_Color *colors, int firstcolor, int ncolors\fR); |
| .SH "DESCRIPTION" |
| .PP |
| Sets a portion of the colormap for the given 8-bit surface\&. |
| .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_SetColors\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\&. |
| .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)\&. \fBSDL_SetColors\fP modifies both palettes (if present), and is equivalent to calling \fISDL_SetPalette\fR with the \fBflags\fR set to \fB(SDL_LOGPAL | SDL_PHYSPAL)\fP\&. |
| .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_SetColors\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_SetColors(screen, colors, 0, 256); |
| \&. |
| \&. |
| \&. |
| \&.\fR |
| .fi |
| .PP |
| .SH "SEE ALSO" |
| .PP |
| \fI\fBSDL_Color\fR\fR \fI\fBSDL_Surface\fR\fR, \fI\fBSDL_SetPalette\fP\fR, \fI\fBSDL_SetVideoMode\fP\fR |
| .\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01 |