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Date: Wed, 1 Feb 2006 18:20:33 -0800 From: Eric Wing Subject: SDL/Universal Binary updates Hi Sam, Attached is a big set of changes to the Xcode projects to support Universal Binaries. I have also included .dmgs that include the prebuilt frameworks. Ryan, I also updated SMPEG which is also in the package. The SDL and smpeg binaries were built against the CVS version (pulled maybe a month ago?). I do not have an Intel Mac to test on so I have no idea if this stuff actually works. However, Christian Walther has been a big help in testing 10.2.8 and 10.3.9 so I'm fairly confident we got the build settings correct for at least PPC. I have attempted to document the important things for producing these Universal Binaries. Documentation is somewhat scattered through out everything, but there is a big centralized piece of documentation in the UniversalBinaryNotes.rtf in the SDL.dmg. As far as Universal Binaries are concerned, the big things were: - Build with gcc 3.3 on PPC, 4.0 on Intel. - We couldn't get any of the MMX/SSE code to compile/link (SDL and smpeg). - All 3rd party dependencies had to be rebuilt as Universal There were also a bunch of non-Universal things that have been updated: - I converted the SDL-satellites to create .dmg's instead of .pkg installers - Updated all 3rd party static libraries with current versions. (I think libpng was the most dramatic going from 1.0.? to 1.2.8 with API breakage. I haven't found any problems so far in doing this.) - Changed some compiler optimization settings - Finally updated the exports list for SDL_mixer - Tried to include a static smpeg in SDL_mixer (multiple build variants in Xcode project now) - Enabled Altivec in SDL (we forgot to add the flags to Xcode last time) - More documentation Since so many things have changed, there might be new problems introduced. The big issue I've found so far is with SDL_mixer. As I mentioned on the mailing list, MP3's produce an assertion failure. And the MikMod problem reported on Bugzilla continues to persist. There's probably a bunch of other stuff I'm forgetting. There really were hundreds of little things I mucked with so it's hard to remember them all. If you have any questions, feel free to ask. Thanks, Eric
author Sam Lantinga <slouken@libsdl.org>
date Thu, 02 Feb 2006 06:26:39 +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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>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
></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
CLASS="NOTE"
><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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><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
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