view docs/html/sdlmixaudio.html @ 4207:a673f44949d6 SDL-1.2

Fixed bug #562 this patch by Diego Pettenò <flameeyes@gentoo.org> for SDL-1.2: The attached patch applies over latest ~arch SDL version, and allows to use the xinerama support to launch an application full screened on the head "0". The SDL_VIDEO_FULLSCREEN_HEAD environment variable sets the head on which the full screen will be displayed, but if you set it to 0, the code simply ignores it as unset. My patch changes the unset value to -1, so that the 0 value can be used correctly. Without this, trying to get fullscreen on head 0 would get the same result than not having xinerama enabled at all. http://sources.gentoo.org/media-libs/libsdl/files/libsdl-1.2.11-xinerama-head-0.patch SDL-1.3 doesnt seem to have any code like this, but it's still good for SDL-1.2
author Sam Lantinga <slouken@libsdl.org>
date Mon, 21 Sep 2009 07:20:51 +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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><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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>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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><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
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><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
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