view docs/html/sdlmixaudio.html @ 757:4f46fee887fe

Date: Sun, 14 Dec 2003 15:16:12 +0100 From: Stephane Marchesin Subject: Re: [SDL] compile problem with sdl <-> alsa The attathced patch does the trick (although there will have to be code changes when the alsa 0.9 api get deprecated). On a side-note, the good news is that using alsa 1.0.0rc1 solves the previous issues I had with my ac97 via sound chipset.
author Sam Lantinga <slouken@libsdl.org>
date Tue, 16 Dec 2003 13:16:50 +0000
parents e5bc29de3f0a
children 355632dca928
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><H1
><A
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>SDL_MixAudio</A
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><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN6719"
></A
><H2
>Name</H2
>SDL_MixAudio&nbsp;--&nbsp;Mix audio data</DIV
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>Synopsis</H2
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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
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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
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><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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><H2
>See Also</H2
><P
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><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
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