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N Sep 17 8791 Sam Lantinga Re: tks source released
Date: Sun, 07 Sep 2003 02:51:58 +0200
From: Stephane Marchesin
Subject: [SDL] Two little patches
Compiling SDL with a recent gcc (gcc 3.3.1, 3.3 doesn't have this
behaviour) gives some nasty warnings :
SDL_blit_A.c: In function `BlitRGBtoRGBSurfaceAlpha128MMX':
SDL_blit_A.c:223: warning: integer constant is too large for "long" type
SDL_blit_A.c:225: warning: integer constant is too large for "long" type
SDL_blit_A.c:227: warning: integer constant is too large for "long" type
[...]
The first attached patch (longlongfix.patch) tells gcc to really treat
those constants as unsigned long long and not long.
The second patch (nasinclude.patch) fixes an include problem I had while
compiling nas audio : when the <audio/audiolib.h> file lies in
/usr/X11R6/include, a -I/usr/X11R6/include option is needed or the file
isn't found.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sun, 21 Sep 2003 18:32:04 +0000 |
parents | e5bc29de3f0a |
children | 355632dca928 |
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<HTML ><HEAD ><TITLE >SDL_MixAudio</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.64 "><LINK REL="HOME" TITLE="SDL Library Documentation" HREF="index.html"><LINK REL="UP" TITLE="Audio" HREF="audio.html"><LINK REL="PREVIOUS" TITLE="SDL_ConvertAudio" HREF="sdlconvertaudio.html"><LINK REL="NEXT" TITLE="SDL_LockAudio" HREF="sdllockaudio.html"></HEAD ><BODY CLASS="REFENTRY" BGCOLOR="#FFF8DC" TEXT="#000000" LINK="#0000ee" VLINK="#551a8b" ALINK="#ff0000" ><DIV CLASS="NAVHEADER" ><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="sdlconvertaudio.html" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdllockaudio.html" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLMIXAUDIO" >SDL_MixAudio</A ></H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN6719" ></A ><H2 >Name</H2 >SDL_MixAudio -- Mix audio data</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN6722" ></A ><H2 >Synopsis</H2 ><DIV CLASS="FUNCSYNOPSIS" ><A NAME="AEN6723" ></A ><P ></P ><PRE CLASS="FUNCSYNOPSISINFO" >#include "SDL.h"</PRE ><P ><CODE ><CODE CLASS="FUNCDEF" >void <B CLASS="FSFUNC" >SDL_MixAudio</B ></CODE >(Uint8 *dst, Uint8 *src, Uint32 len, int volume);</CODE ></P ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6729" ></A ><H2 >Description</H2 ><P >This function takes two audio buffers of <TT CLASS="PARAMETER" ><I >len</I ></TT > bytes each of the playing audio format and mixes them, performing addition, volume adjustment, and overflow clipping. The <TT CLASS="PARAMETER" ><I >volume</I ></TT > ranges from 0 to <TT CLASS="LITERAL" >SDL_MIX_MAXVOLUME</TT > and should be set to the maximum value for full audio volume. Note this does not change hardware volume. This is provided for convenience -- you can mix your own audio data.</P ><DIV CLASS="NOTE" ><BLOCKQUOTE CLASS="NOTE" ><P ><B >Note: </B >Do not use this function for mixing together more than two streams of sample data. The output from repeated application of this function may be distorted by clipping, because there is no accumulator with greater range than the input (not to mention this being an inefficient way of doing it). Use mixing functions from SDL_mixer, OpenAL, or write your own mixer instead.</P ></BLOCKQUOTE ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6737" ></A ><H2 >See Also</H2 ><P ><A HREF="sdlopenaudio.html" ><TT CLASS="FUNCTION" >SDL_OpenAudio</TT ></A ></P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="sdlconvertaudio.html" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="sdllockaudio.html" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_ConvertAudio</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="audio.html" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_LockAudio</TD ></TR ></TABLE ></DIV ></BODY ></HTML >