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1 | .TH "SDL_SetColors" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" |
2 | .SH "NAME" |
3 | SDL_SetColors \- Sets a portion of the colormap for the given 8-bit surface\&. |
4 | .SH "SYNOPSIS" |
5 | .PP |
6 | \fB#include "SDL\&.h" |
7 | .sp |
8 | \fBint \fBSDL_SetColors\fP\fR(\fBSDL_Surface *surface, SDL_Color *colors, int firstcolor, int ncolors\fR); |
9 | .SH "DESCRIPTION" |
10 | .PP |
11 | Sets a portion of the colormap for the given 8-bit surface\&. |
12 | .PP |
13 | 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\&. |
14 | .PP |
15 | 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\&. |
16 | .PP |
17 | 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\&. |
18 | .SH "RETURN VALUE" |
19 | .PP |
20 | 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\&. |
21 | .SH "EXAMPLE" |
22 | .PP |
23 | .nf |
24 | \f(CW/* Create a display surface with a grayscale palette */ |
25 | SDL_Surface *screen; |
26 | SDL_Color colors[256]; |
27 | int i; |
28 | \&. |
29 | \&. |
30 | \&. |
31 | /* Fill colors with color information */ |
32 | for(i=0;i<256;i++){ |
33 | colors[i]\&.r=i; |
34 | colors[i]\&.g=i; |
35 | colors[i]\&.b=i; |
36 | } |
37 | |
38 | /* Create display */ |
39 | screen=SDL_SetVideoMode(640, 480, 8, SDL_HWPALETTE); |
40 | if(!screen){ |
41 | printf("Couldn\&'t set video mode: %s |
42 | ", SDL_GetError()); |
43 | exit(-1); |
44 | } |
45 | |
46 | /* Set palette */ |
47 | SDL_SetColors(screen, colors, 0, 256); |
48 | \&. |
49 | \&. |
50 | \&. |
51 | \&.\fR |
52 | .fi |
53 | .PP |
54 | .SH "SEE ALSO" |
55 | .PP |
56 | \fI\fBSDL_Color\fR\fR \fI\fBSDL_Surface\fR\fR, \fI\fBSDL_SetPalette\fP\fR, \fI\fBSDL_SetVideoMode\fP\fR |
57 | .\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01 |