view docs/html/sdlmixaudio.html @ 2144:665c2669e6a3

Merged r3138:3139 from branches/SDL-1.2: Don't init audio callback buffer. (This already had a concession for devices opened via the 1.2 entry points, I've changed it to respect the environment variable and do it for all devices now.)
author Ryan C. Gordon <icculus@icculus.org>
date Thu, 05 Jul 2007 02:30:10 +0000
parents 355632dca928
children
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><H1
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>SDL_MixAudio</H1
><DIV
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><A
NAME="AEN7107"
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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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><P
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><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
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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
><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
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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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