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view docs/html/sdlsemvalue.html @ 3880:74e828c64315 SDL-1.2

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Fixed bug #292 I might be on crack here. It looks like SDL_ConvertMono() in src/audio/SDL_audiocvt.c adds the left and right channels of a stereo stream together, and clamps the new mono channel if it would overflow. Shouldn't it be dividing by 2 to average the two sample points instead of clamping? Otherwise the mono sample point's volume doubles in the conversion. This would also make the conversion faster, as it replaces two branches per sample frame with a bitwise shift. --ryan.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 24 Sep 2006 15:45:37 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>SDL_SemValue</TITLE
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><H1
><A
NAME="SDLSEMVALUE"
></A
>SDL_SemValue</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN8218"
></A
><H2
>Name</H2
>SDL_SemValue&nbsp;--&nbsp;Return the current value of a semaphore.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN8221"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN8222"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"
#include "SDL/SDL_thread.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>Uint32 <B
CLASS="FSFUNC"
>SDL_SemValue</B
></CODE
>(SDL_sem *sem);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN8228"
></A
><H2
>Description</H2
><P
><TT
CLASS="FUNCTION"
>SDL_SemValue()</TT
> returns the current semaphore value from
the semaphore pointed to by <TT
CLASS="PARAMETER"
><I
>sem</I
></TT
>.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN8233"
></A
><H2
>Return Value</H2
><P
>Returns current value of the semaphore.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN8236"
></A
><H2
>Examples</H2
><P
><PRE
CLASS="PROGRAMLISTING"
>  sem_value = SDL_SemValue(my_sem);</PRE
></P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN8240"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlcreatesemaphore.html"
><TT
CLASS="FUNCTION"
>SDL_CreateSemaphore</TT
></A
>,
<A
HREF="sdldestroysemaphore.html"
><TT
CLASS="FUNCTION"
>SDL_DestroySemaphore</TT
></A
>,
<A
HREF="sdlsemwait.html"
><TT
CLASS="FUNCTION"
>SDL_SemWait</TT
></A
>,
<A
HREF="sdlsemtrywait.html"
><TT
CLASS="FUNCTION"
>SDL_SemTryWait</TT
></A
>,
<A
HREF="sdlsemwaittimeout.html"
><TT
CLASS="FUNCTION"
>SDL_SemWaitTimeout</TT
></A
>,
<A
HREF="sdlsempost.html"
><TT
CLASS="FUNCTION"
>SDL_SemPost</TT
></A
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