Mercurial > sdl-ios-xcode
annotate docs/man3/SDL_Palette.3 @ 997:3bf4103b2b89
Date: Sat, 27 Nov 2004 13:35:43 +0100
From: "Martin Bickel"
Subject: [SDL] Patch: fixing uninitilized palette
while running Valgrind over my application I found the following
problem in SDL:
The function MapNto1 allocates SDL_Color colors[256] but does not
initialize it.
SDL_DitherColors is then called which initialized the r, g and b
component, but not the 'unused' component of each color.
When Map1to1 is called from MapNto1, it runs a memcmp on the colors,
which also evaluates the unused component and therefor returns
differences much more often than necessary.
So the 'unused' component of SDL_Color should be initialized. This
patch does this by calling memset for the whole array in MapNto1 .
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Tue, 30 Nov 2004 14:28:20 +0000 |
parents | e5bc29de3f0a |
children | 546f7c1eb755 |
rev | line source |
---|---|
181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
1 .TH "SDL_Palette" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" |
0 | 2 .SH "NAME" |
3 SDL_Palette\- Color palette for 8-bit pixel formats | |
4 .SH "STRUCTURE DEFINITION" | |
5 .PP | |
6 .nf | |
7 \f(CWtypedef struct{ | |
8 int ncolors; | |
9 SDL_Color *colors; | |
10 } SDL_Palette;\fR | |
11 .fi | |
12 .PP | |
13 .SH "STRUCTURE DATA" | |
14 .TP 20 | |
15 \fBncolors\fR | |
16 Number of colors used in this palette | |
17 .TP 20 | |
18 \fBcolors\fR | |
19 Pointer to \fI\fBSDL_Color\fR\fR structures that make up the palette\&. | |
20 .SH "DESCRIPTION" | |
21 .PP | |
22 Each pixel in an 8-bit surface is an index into the \fBcolors\fR field of the \fBSDL_Palette\fR structure store in \fI\fBSDL_PixelFormat\fR\fR\&. A \fBSDL_Palette\fR should never need to be created manually\&. It is automatically created when SDL allocates a \fBSDL_PixelFormat\fR for a surface\&. The colors values of a \fI\fBSDL_Surface\fR\fRs palette can be set with the \fI\fBSDL_SetColors\fP\fR\&. | |
23 .SH "SEE ALSO" | |
24 .PP | |
25 \fI\fBSDL_Color\fR\fR, \fI\fBSDL_Surface\fR\fR, \fI\fBSDL_SetColors\fP\fR \fI\fBSDL_SetPalette\fP\fR | |
181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
26 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01 |