view docs/html/sdlmixaudio.html @ 1138:fcfb783a3ca2

Commercial-OSS-on-Solaris patch... --ryan. Date: Sun, 14 Aug 2005 23:06:40 -0500 From: Shawn Walker <binarycrusader@gmail.com> To: sdl@libsdl.org Subject: [SDL] [PATCH] Audio Detection Bug When using the OSS commercial drivers under Solaris 10, SDL will not properly initialise OSS audio support (dsp) if /dev/sound exists. Under Solaris (as far as I understand) /dev/sound is provided as a means of accessing a BSD style audio device, not the OSS device. SDL assumes that if /dev/sound exists, then it must be running on a Linux 2.4 system and should make the dsp device path /dev/sound/dsp. This is wrong. When using the OSS commercial drivers under Solaris, the dsp device is always referenced as /dev/dsp normally. My proposed fix is to stat the dsp device in /dev/sound to make sure it exists, before assuming /dev/sound/dsp as the audio device: http://icculus.org/~eviltypeguy/SDL_audiodev.patch I'm sure there may be a better way to do it, but the above patch is what worked for me. --=20 Shawn Walker, Software and Systems Analyst binarycrusader@gmail.com - http://binarycrusader.blogspot.com/
author Ryan C. Gordon <icculus@icculus.org>
date Thu, 08 Sep 2005 07:15:44 +0000
parents 355632dca928
children
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>SDL_MixAudio</H1
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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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><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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>See Also</H2
><P
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HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
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