view docs/html/sdlmixaudio.html @ 270:37fa1484f71b

From: "Mattias Engdeg�rd" <f91-men@nada.kth.se> To: slouken@devolution.com Subject: Re: [SDL] Question about SDL_FillRect() I benchmarked with and without clipping UpdateRects and was unable to find any difference on my moderately slow machine. Anyway, I haven't added clipping in this patch, but fixed a couple of bugs and generally cleaned up some of the X11 image code. Most importantly, UpdateRects now checks for both zero height and width. Also, I eliminated the entire code to byteswap X11 images since X11 can do that automatically if you ask it nicely :-)
author Sam Lantinga <slouken@libsdl.org>
date Fri, 18 Jan 2002 22:02:03 +0000
parents e5bc29de3f0a
children 355632dca928
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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
><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
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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
><A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
></A
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