Mercurial > sdl-ios-xcode
view docs/man3/SDL_Flip.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 |
line wrap: on
line source
.TH "SDL_Flip" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" .SH "NAME" SDL_Flip\- Swaps screen buffers .SH "SYNOPSIS" .PP \fB#include "SDL\&.h" .sp \fBint \fBSDL_Flip\fP\fR(\fBSDL_Surface *screen\fR); .SH "DESCRIPTION" .PP On hardware that supports double-buffering, this function sets up a flip and returns\&. The hardware will wait for vertical retrace, and then swap video buffers before the next video surface blit or lock will return\&. On hardware that doesn\&'t support double-buffering, this is equivalent to calling \fISDL_UpdateRect\fR\fB(screen, 0, 0, 0, 0)\fR .PP The \fBSDL_DOUBLEBUF\fP flag must have been passed to \fISDL_SetVideoMode\fR, when setting the video mode for this function to perform hardware flipping\&. .SH "RETURN VALUE" .PP This function returns \fB0\fR if successful, or \fB-1\fR if there was an error\&. .SH "SEE ALSO" .PP \fI\fBSDL_SetVideoMode\fP\fR, \fI\fBSDL_UpdateRect\fP\fR, \fI\fBSDL_Surface\fR\fR ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01