view docs/html/sdlmixaudio.html @ 3925:78ff7d10dbb5 SDL-1.2

From: Laurence Passmore Date: Mon, 26 Mar 2007 23:22:45 +0100 To: "A list for developers using the SDL library. \(includes SDL-announce\)" <sdl@lists.libsdl.org> Subject: [SDL] SDL_config_macosx.h: MAC_OS_X_VERSION_MIN_REQUIRED Hi, I just compiled my SDL application on Mac OS X with -Wundef and it threw a number of errors. Of note was: SDL_config_macosx.h: 34 warning: "MAC_OS_X_VERSION_MIN_REQUIRED" is not defined Line 34 is: #if ( (MAC_OS_X_VERSION_MIN_REQUIRED >= 1030) || (!defined (__POWERPC__)) ) Now according to this mailing on the Apple developer lists: http://lists.apple.com/archives/Xcode-users/2005/May/msg00602.html that particular #define was removed from the gcc compiler defaults and AvailabilityMacros.h (/usr/include/AvailabilityMacros.h) should be pulled in directly instead. Would someone closer to the Mac OS X version of SDL be willing to make that change please? Thanks. Laurence Passmore Homeworld SDL @ www.homeworldsdl.org
author Ryan C. Gordon <icculus@icculus.org>
date Tue, 27 Mar 2007 00:37:51 +0000
parents 355632dca928
children
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>SDL_MixAudio</H1
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><H2
>Name</H2
>SDL_MixAudio&nbsp;--&nbsp;Mix audio data</DIV
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>Synopsis</H2
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><PRE
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>#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
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><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
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><BLOCKQUOTE
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><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
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>See Also</H2
><P
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HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
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