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Date: Sat, 06 Dec 2008 15:27:00 +0100 From: Couriersud Subject: SDL: Relative mouse movements The patch below will reenable processing of relative mouse movements. The DirectFB drivers generates those in "grabbed" mode. These ensure, that even in fullscreen mode relative movements are reported. SDLMAME depends on this for games with trackballs. Looking at the code I ask myself whether relative movements should be handled in the drivers (x11, directfb). Both x11 and directfb are able to report relative movements. This would leave it to the driver to use the most appropriate method for relative movements when at the border of a fullscreen window or being "grabbed".
author Sam Lantinga <slouken@libsdl.org>
date Sat, 06 Dec 2008 17:50:50 +0000
parents 355632dca928
children
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<HTML
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>SDL_CreateSemaphore</TITLE
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><H1
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>SDL_CreateSemaphore</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN7936"
></A
><H2
>Name</H2
>SDL_CreateSemaphore&nbsp;--&nbsp;Creates a new semaphore and assigns an initial value to it.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN7939"
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><H2
>Synopsis</H2
><DIV
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><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"
#include "SDL_thread.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>SDL_sem *<B
CLASS="FSFUNC"
>SDL_CreateSemaphore</B
></CODE
>(Uint32 initial_value);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN7946"
></A
><H2
>Description</H2
><P
><TT
CLASS="FUNCTION"
>SDL_CreateSemaphore()</TT
> creates a new semaphore and
initializes it with the value <TT
CLASS="PARAMETER"
><I
>initial_value</I
></TT
>.
Each locking operation on the semaphore by
<A
HREF="sdlsemwait.html"
>SDL_SemWait</A
>,
<A
HREF="sdlsemtrywait.html"
>SDL_SemTryWait</A
> or
<A
HREF="sdlsemwaittimeout.html"
>SDL_SemWaitTimeout</A
>
will atomically decrement the semaphore value. The locking operation will be blocked
if the semaphore value is not positive (greater than zero). Each unlock operation by
<A
HREF="sdlsempost.html"
>SDL_SemPost</A
>
will atomically increment the semaphore value.</P
></DIV
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><A
NAME="AEN7955"
></A
><H2
>Return Value</H2
><P
>Returns a pointer to an initialized semaphore or
<SPAN
CLASS="RETURNVALUE"
>NULL</SPAN
> if there was an error.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN7959"
></A
><H2
>Examples</H2
><P
><PRE
CLASS="PROGRAMLISTING"
>SDL_sem *my_sem;

my_sem = SDL_CreateSemaphore(INITIAL_SEM_VALUE);

if (my_sem == NULL) {
        return CREATE_SEM_FAILED;
}</PRE
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><H2
>See Also</H2
><P
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HREF="sdldestroysemaphore.html"
><TT
CLASS="FUNCTION"
>SDL_DestroySemaphore</TT
></A
>,
<A
HREF="sdlsemwait.html"
><TT
CLASS="FUNCTION"
>SDL_SemWait</TT
></A
>,
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><TT
CLASS="FUNCTION"
>SDL_SemTryWait</TT
></A
>,
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><TT
CLASS="FUNCTION"
>SDL_SemWaitTimeout</TT
></A
>,
<A
HREF="sdlsempost.html"
><TT
CLASS="FUNCTION"
>SDL_SemPost</TT
></A
>,
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><TT
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>SDL_SemValue</TT
></A
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