view docs/html/sdlmixaudio.html @ 1812:9c882e94b545

Fixed bug #208 So, here's a patch with a reimplementation of QZ_SetIcon() that does what I described above. I apologize for the delay, I've been quite busy in the last few days. It appears to work here on 10.4.5 PPC in the limited testing that I've done; I'll try to test it on 10.3.9 and 10.2.8 as well, but that might take another week or so. Please test on i386. Regarding alpha channels, per-surface alpha, and color keys, the same semantics as for regular blits to an RGB surface should apply (for the final icon composited onto the dock), unless I made a mistake - except in one pathological case: if the icon surface has an alpha channel, its SDL_SRCALPHA flag is not set (i.e. it has been explicitly cleared, since it's on by default for RGBA surfaces), and it has a color key, plus an explicit mask was specified (instead of the one autogenerated from the colorkey), then the color-keyed areas appear black instead of transparent. I found no elegant way of fixing this, was too lazy to implement the inelegant one, and decided that it isn't worth the effort (but if someone disagrees, I can do it).
author Sam Lantinga <slouken@libsdl.org>
date Thu, 11 May 2006 03:45:55 +0000
parents 355632dca928
children
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>SDL_MixAudio</H1
><DIV
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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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><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
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
><A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
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