view docs/html/sdlmixaudio.html @ 3097:0d12e8f1de3c

Date: Thu, 05 Feb 2009 18:07:35 +0100 From: Stefan Klug Subject: [SDL] SDL 1.3 WinCE backend as promised, I've started to work on the WinCE backend of SDL 1.3 I've modified the win32 video backend and the gdi renderer, to work properly in WinCE. The results till now are great, but there is still some work to do. Attached are two patches with my changes. I would be happy if someone could review and propably commit them. The first one (configure.in.patch) should be straight forward without any side effects. The second one does the necessary changes to the win32 backend. I was really unhappy to start slicing this shiny new backend with #ifdef/#endif but I saw no other option. The most problematic issues are: - WinCe has no GetDIBits, so its practically impossible to fill a BITMAPINFO with correct values. I therefore removed the bmi member from the GDI_RenderData in SDL_gdirender.c to prevent usage of a not or not properly initialized bmi. - In SDL_win32window.c I exchanged some ASCII function by their general counterparts, (In CE only the Unicode versions are available). I don't know if this has a negative effect when running in win32 Cheers Stefan
author Sam Lantinga <slouken@libsdl.org>
date Mon, 23 Mar 2009 05:35:21 +0000
parents 355632dca928
children
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>SDL_MixAudio</H1
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><A
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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
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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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><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
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>See Also</H2
><P
><A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
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