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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 15:56:36 +0000
parents 355632dca928
children
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<HTML
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>SDL_PeepEvents</TITLE
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><H1
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>SDL_PeepEvents</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN5421"
></A
><H2
>Name</H2
>SDL_PeepEvents&nbsp;--&nbsp;Checks the event queue for messages and optionally returns them.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN5424"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN5425"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_PeepEvents</B
></CODE
>(SDL_Event *events, int numevents, SDL_eventaction action, Uint32 mask);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN5431"
></A
><H2
>Description</H2
><P
>Checks the event queue for messages and optionally returns them.</P
><P
>If <TT
CLASS="PARAMETER"
><I
>action</I
></TT
> is <TT
CLASS="LITERAL"
>SDL_ADDEVENT</TT
>, up to 
<TT
CLASS="PARAMETER"
><I
>numevents</I
></TT
> events will be added to the back of the event
 queue.</P
><P
>If <TT
CLASS="PARAMETER"
><I
>action</I
></TT
> is <TT
CLASS="LITERAL"
>SDL_PEEKEVENT</TT
>, up to
<TT
CLASS="PARAMETER"
><I
>numevents</I
></TT
> events at the front of the event queue, 
matching <A
HREF="sdlevent.html"
><TT
CLASS="PARAMETER"
><I
>mask</I
></TT
></A
>, 
will be returned and will not be removed from the queue.</P
><P
>If <TT
CLASS="PARAMETER"
><I
>action</I
></TT
> is <TT
CLASS="LITERAL"
>SDL_GETEVENT</TT
>, up to 
<TT
CLASS="PARAMETER"
><I
>numevents</I
></TT
> events at the front of the event queue, 
matching <A
HREF="sdlevent.html"
><TT
CLASS="PARAMETER"
><I
>mask</I
></TT
></A
>, 
will be returned and will be removed from the queue.</P
><P
>The <TT
CLASS="PARAMETER"
><I
>mask</I
></TT
> parameter is an bitwise OR of
<TT
CLASS="LITERAL"
>SDL_EVENTMASK</TT
>(<TT
CLASS="PARAMETER"
><I
>event_type</I
></TT
>), for all
event types you are interested in.</P
><P
>This function is thread-safe.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN5455"
></A
><H2
>Return Value</H2
><P
>This function returns the number of events actually stored, or 
<SPAN
CLASS="RETURNVALUE"
>-1</SPAN
> if there was an error.  </P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN5459"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
></A
>,
<A
HREF="sdlpollevent.html"
><TT
CLASS="FUNCTION"
>SDL_PollEvent</TT
></A
>,
<A
HREF="sdlpushevent.html"
><TT
CLASS="FUNCTION"
>SDL_PushEvent</TT
></A
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