view docs/html/sdlsempost.html @ 3335:b8d313de8a65

Adam Strzelecki to SDL Since current DirectFB implementation is incomplete for YUV surfaces (actually causes segmentation faults when trying Lock and use YUV planar textures) I decided to fix it a bit. Here's a patch that should make DirectFB properly support YUV both packed and planar (3 planes). (1) Removed SDL_BYTESPERPIXEL at all in favor of DFB_BYTES_PER_PIXEL(SDLToDFBPixelFormat(fmt)) which does return always proper BPP for YUVs too, coz SDL_BYTESPERPIXEL returns incorrect values for FOURCCs (2) Fixed data->pixels allocation for planar YUVs in CreateTexture, it should allocate 150% more space (3) Copy other planes for planar YUVs in UpdateTexture (4) Moved checking if format is supported at all with DirectFB on CreateTexture at the beginning of the code Waiting for comments, -- Adam Strzelecki | nanoant.com
author Sam Lantinga <slouken@libsdl.org>
date Sun, 04 Oct 2009 04:03:37 +0000
parents 355632dca928
children
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><H1
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>SDL_SemPost</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN8170"
></A
><H2
>Name</H2
>SDL_SemPost&nbsp;--&nbsp;Unlock a semaphore.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN8173"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
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><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"
#include "SDL_thread.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_SemPost</B
></CODE
>(SDL_sem *sem);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN8180"
></A
><H2
>Description</H2
><P
><TT
CLASS="FUNCTION"
>SDL_SemPost</TT
> unlocks the semaphore pointed to by
<TT
CLASS="PARAMETER"
><I
>sem</I
></TT
> and atomically increments the semaphores value.
Threads that were blocking on the semaphore may be scheduled after this call
succeeds.</P
><P
><TT
CLASS="FUNCTION"
>SDL_SemPost</TT
> should be called after a semaphore is locked by a successful call to
<A
HREF="sdlsemwait.html"
>SDL_SemWait</A
>,
<A
HREF="sdlsemtrywait.html"
>SDL_SemTryWait</A
> or
<A
HREF="sdlsemwaittimeout.html"
>SDL_SemWaitTimeout</A
>.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN8190"
></A
><H2
>Return Value</H2
><P
>Returns <SPAN
CLASS="RETURNVALUE"
>0</SPAN
> if successful or
<SPAN
CLASS="RETURNVALUE"
>-1</SPAN
> if there was an error (leaving the semaphore unchanged).</P
></DIV
><DIV
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><A
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></A
><H2
>Examples</H2
><P
><PRE
CLASS="PROGRAMLISTING"
>SDL_SemPost(my_sem);</PRE
></P
></DIV
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><A
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></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="sdlsemvalue.html"
><TT
CLASS="FUNCTION"
>SDL_SemValue</TT
></A
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