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view docs/html/sdlglsetattribute.html @ 3880:74e828c64315 SDL-1.2

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Fixed bug #292 I might be on crack here. It looks like SDL_ConvertMono() in src/audio/SDL_audiocvt.c adds the left and right channels of a stereo stream together, and clamps the new mono channel if it would overflow. Shouldn't it be dividing by 2 to average the two sample points instead of clamping? Otherwise the mono sample point's volume doubles in the conversion. This would also make the conversion faster, as it replaces two branches per sample frame with a bitwise shift. --ryan.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 24 Sep 2006 15:45:37 +0000
parents 355632dca928
children
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><H1
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>SDL_GL_SetAttribute</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN2742"
></A
><H2
>Name</H2
>SDL_GL_SetAttribute&nbsp;--&nbsp;Set a special SDL/OpenGL attribute</DIV
><DIV
CLASS="REFSYNOPSISDIV"
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><H2
>Synopsis</H2
><DIV
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><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_GL_SetAttribute</B
></CODE
>(SDL_GLattr attr, int value);</CODE
></P
><P
></P
></DIV
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><DIV
CLASS="REFSECT1"
><A
NAME="AEN2752"
></A
><H2
>Description</H2
><P
>Sets the OpenGL <A
HREF="sdlglattr.html"
>attribute</A
> <TT
CLASS="PARAMETER"
><I
>attr</I
></TT
> to <TT
CLASS="PARAMETER"
><I
>value</I
></TT
>. The attributes you set don't take effect until after a call to <A
HREF="sdlsetvideomode.html"
><TT
CLASS="FUNCTION"
>SDL_SetVideoMode</TT
></A
>. You should use <A
HREF="sdlglgetattribute.html"
><TT
CLASS="FUNCTION"
>SDL_GL_GetAttribute</TT
></A
> to check the values after a <TT
CLASS="FUNCTION"
>SDL_SetVideoMode</TT
> call.</P
></DIV
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></A
><H2
>Return Value</H2
><P
>Returns <SPAN
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>0</SPAN
> on success, or <SPAN
CLASS="RETURNVALUE"
>-1</SPAN
> on error.</P
></DIV
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><A
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></A
><H2
>Example</H2
><PRE
CLASS="PROGRAMLISTING"
>SDL_GL_SetAttribute( SDL_GL_RED_SIZE, 5 );
SDL_GL_SetAttribute( SDL_GL_GREEN_SIZE, 5 );
SDL_GL_SetAttribute( SDL_GL_BLUE_SIZE, 5 );
SDL_GL_SetAttribute( SDL_GL_DEPTH_SIZE, 16 );
SDL_GL_SetAttribute( SDL_GL_DOUBLEBUFFER, 1 );
if ( (screen=SDL_SetVideoMode( 640, 480, 16, SDL_OPENGL )) == NULL ) {
  fprintf(stderr, "Couldn't set GL mode: %s\n", SDL_GetError());
  SDL_Quit();
  return;
}</PRE
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>Note: </B
>The <TT
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>SDL_DOUBLEBUF</TT
> flag is not required to enable double buffering when setting an OpenGL video mode. Double buffering is enabled or disabled using the SDL_GL_DOUBLEBUFFER attribute.</P
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><A
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><TT
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>SDL_GL_GetAttribute</TT
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>,
<A
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