Mercurial > sdl-ios-xcode
view docs/html/sdlglattr.html @ 3880:74e828c64315 SDL-1.2
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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<HTML ><HEAD ><TITLE >SDL_GLattr</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_FreeYUVOverlay" HREF="sdlfreeyuvoverlay.html"><LINK REL="NEXT" TITLE="SDL_Rect" HREF="sdlrect.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="sdlfreeyuvoverlay.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlrect.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLGLATTR" ></A >SDL_GLattr</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN2971" ></A ><H2 >Name</H2 >SDL_GLattr -- SDL GL Attributes</DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN2974" ></A ><H2 >Attributes</H2 ><DIV CLASS="INFORMALTABLE" ><A NAME="AEN2976" ></A ><P ></P ><TABLE BORDER="0" CLASS="CALSTABLE" ><TBODY ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_GL_RED_SIZE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Size of the framebuffer red component, in bits</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_GL_GREEN_SIZE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Size of the framebuffer green component, in bits</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_GL_BLUE_SIZE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Size of the framebuffer blue component, in bits</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_GL_ALPHA_SIZE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Size of the framebuffer alpha component, in bits</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_GL_DOUBLEBUFFER</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >0 or 1, enable or disable double buffering</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_GL_BUFFER_SIZE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Size of the framebuffer, in bits</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_GL_DEPTH_SIZE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Size of the depth buffer, in bits</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_GL_STENCIL_SIZE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Size of the stencil buffer, in bits</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_GL_ACCUM_RED_SIZE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Size of the accumulation buffer red component, in bits</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_GL_ACCUM_GREEN_SIZE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Size of the accumulation buffer green component, in bits</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_GL_ACCUM_BLUE_SIZE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Size of the accumulation buffer blue component, in bits</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_GL_ACCUM_ALPHA_SIZE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Size of the accumulation buffer alpha component, in bits</TD ></TR ></TBODY ></TABLE ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN3027" ></A ><H2 >Description</H2 ><P >While you can set most OpenGL attributes normally, the attributes list above must be known <SPAN CLASS="emphasis" ><I CLASS="EMPHASIS" >before</I ></SPAN > SDL sets the video mode. These attributes a set and read with <A HREF="sdlglsetattribute.html" ><TT CLASS="FUNCTION" >SDL_GL_SetAttribute</TT ></A > and <A HREF="sdlglgetattribute.html" ><TT CLASS="FUNCTION" >SDL_GL_GetAttribute</TT ></A >.</P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN3035" ></A ><H2 >See Also</H2 ><P ><A HREF="sdlglsetattribute.html" ><TT CLASS="FUNCTION" >SDL_GL_SetAttribute</TT ></A >, <A HREF="sdlglgetattribute.html" ><TT CLASS="FUNCTION" >SDL_GL_GetAttribute</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="sdlfreeyuvoverlay.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="sdlrect.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_FreeYUVOverlay</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_Rect</TD ></TR ></TABLE ></DIV ></BODY ></HTML >