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[PATCH] SDL_GetVideoMode() does not find best mode, part 2 Following commit 1.51, I come accross a problem when SDL must choose between several video modes that could suit the one asked. If I ask 320x240 with this list: 768x480 768x240 640x400 640x200 384x480 384x240 320x400 320x200 The smallest selectables modes are 384x240 and 320x400. And SDL choose the later in this list, but 384x240 is more suitable. So I added a check to compare the pixel count (surface) of modes, and select the one which has the smallest pixel count. In my example, 384x240 has 92160 pixels, and 320x400 has 128000 pixels. So now SDL will choose 384x240 for the asked 320x240 mode.
author Patrice Mandin <patmandin@gmail.com>
date Thu, 19 Jan 2006 21:28:52 +0000
parents 355632dca928
children
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<HTML
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><TITLE
>SDL_SemWait</TITLE
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><H1
><A
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>SDL_SemWait</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN8023"
></A
><H2
>Name</H2
>SDL_SemWait&nbsp;--&nbsp;Lock a semaphore and suspend the thread if the semaphore value is zero.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN8026"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN8027"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"
#include "SDL_thread.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_SemWait</B
></CODE
>(SDL_sem *sem);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN8033"
></A
><H2
>Description</H2
><P
><TT
CLASS="FUNCTION"
>SDL_SemWait()</TT
> suspends the calling thread until either
the semaphore pointed to by <TT
CLASS="PARAMETER"
><I
>sem</I
></TT
> has a positive value,
the call is interrupted by a signal or error. If the call is successful it
will atomically decrement the semaphore value.</P
><P
>After <TT
CLASS="FUNCTION"
>SDL_SemWait()</TT
> is successful, the semaphore
can be released and its count atomically incremented by a successful call to
<A
HREF="sdlsempost.html"
>SDL_SemPost</A
>.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN8041"
></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
CLASS="REFSECT1"
><A
NAME="AEN8046"
></A
><H2
>Examples</H2
><P
><PRE
CLASS="PROGRAMLISTING"
>if (SDL_SemWait(my_sem) == -1) {
        return WAIT_FAILED;
}

...

SDL_SemPost(my_sem);</PRE
></P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN8050"
></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="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
>,
<A
HREF="sdlsemvalue.html"
><TT
CLASS="FUNCTION"
>SDL_SemValue</TT
></A
></P
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