view docs/html/sdlcreateyuvoverlay.html @ 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 355632dca928
children
line wrap: on
line source

<HTML
><HEAD
><TITLE
>SDL_CreateYUVOverlay</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
"><LINK
REL="HOME"
TITLE="SDL Library Documentation"
HREF="index.html"><LINK
REL="UP"
TITLE="Video"
HREF="video.html"><LINK
REL="PREVIOUS"
TITLE="SDL_GL_SwapBuffers"
HREF="sdlglswapbuffers.html"><LINK
REL="NEXT"
TITLE="SDL_LockYUVOverlay"
HREF="sdllockyuvoverlay.html"></HEAD
><BODY
CLASS="REFENTRY"
BGCOLOR="#FFF8DC"
TEXT="#000000"
LINK="#0000ee"
VLINK="#551a8b"
ALINK="#ff0000"
><DIV
CLASS="NAVHEADER"
><TABLE
SUMMARY="Header navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
>SDL Library Documentation</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="sdlglswapbuffers.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
></TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="sdllockyuvoverlay.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><H1
><A
NAME="SDLCREATEYUVOVERLAY"
></A
>SDL_CreateYUVOverlay</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN2808"
></A
><H2
>Name</H2
>SDL_CreateYUVOverlay&nbsp;--&nbsp;Create a YUV video overlay</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN2811"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN2812"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>SDL_Overlay *<B
CLASS="FSFUNC"
>SDL_CreateYUVOverlay</B
></CODE
>(int width, int height, Uint32 format, SDL_Surface *display);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2818"
></A
><H2
>Description</H2
><P
><TT
CLASS="FUNCTION"
>SDL_CreateYUVOverlay</TT
> creates a YUV overlay of the specified <TT
CLASS="PARAMETER"
><I
>width</I
></TT
>, <TT
CLASS="PARAMETER"
><I
>height</I
></TT
> and <TT
CLASS="PARAMETER"
><I
>format</I
></TT
> (see <A
HREF="sdloverlay.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Overlay</SPAN
></A
> for a list of available formats), for the provided <TT
CLASS="PARAMETER"
><I
>display</I
></TT
>. A <A
HREF="sdloverlay.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Overlay</SPAN
></A
> structure is returned.</P
><P
>The term 'overlay' is a misnomer since, unless the overlay is created in hardware, the contents for the display surface underneath the area where the overlay is shown will be overwritten when the overlay is displayed.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2831"
></A
><H2
>See Also</H2
><P
><A
HREF="sdloverlay.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Overlay</SPAN
></A
>,
<A
HREF="sdldisplayyuvoverlay.html"
><TT
CLASS="FUNCTION"
>SDL_DisplayYUVOverlay</TT
></A
>,
<A
HREF="sdlfreeyuvoverlay.html"
><TT
CLASS="FUNCTION"
>SDL_FreeYUVOverlay</TT
></A
></P
></DIV
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
SUMMARY="Footer navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><A
HREF="sdlglswapbuffers.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="index.html"
ACCESSKEY="H"
>Home</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><A
HREF="sdllockyuvoverlay.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>SDL_GL_SwapBuffers</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="video.html"
ACCESSKEY="U"
>Up</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
>SDL_LockYUVOverlay</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>