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Date: Mon, 14 Apr 2003 22:08:27 +0100 From: Patrice Mandin Subject: [SDL][PATCH] 2 patches for sdl Here are 2 patches for SDL: - One is to put the dummy video drivers at the end of the video drivers list. It gave me problems, when SDL_VIDEODRIVER is not set, and the dummy driver is used instead of the platform's driver, just because it is always available. So the dummy driver must always be at the end of the list. I suppose picogui and dc video drivers also don't work.
author Sam Lantinga <slouken@libsdl.org>
date Tue, 15 Apr 2003 15:46:56 +0000
parents e5bc29de3f0a
children 355632dca928
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<HTML
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>SDL_SetEventFilter</TITLE
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><H1
><A
NAME="SDLSETEVENTFILTER"
>SDL_SetEventFilter</A
></H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN5187"
></A
><H2
>Name</H2
>SDL_SetEventFilter&nbsp;--&nbsp;Sets up a filter to process all events before they are posted 
to the event queue.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN5190"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN5191"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>void <B
CLASS="FSFUNC"
>SDL_SetEventFilter</B
></CODE
>(SDL_EventFilter filter);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN5197"
></A
><H2
>Description</H2
><P
>This function sets up a filter to process all events before they are posted 
to the event queue.  This is a very powerful and flexible feature.  The filter 
is prototyped as:
<PRE
CLASS="PROGRAMLISTING"
>typedef int (*SDL_EventFilter)(const SDL_Event *event);</PRE
>
If the filter returns <SPAN
CLASS="RETURNVALUE"
>1</SPAN
>, then the event will be 
added to the internal queue.  If it returns <SPAN
CLASS="RETURNVALUE"
>0</SPAN
>, 
then the event will be dropped from the queue.  This allows selective
filtering of dynamically.</P
><P
>There is one caveat when dealing with the <TT
CLASS="LITERAL"
>SDL_QUITEVENT</TT
> event type.  The
event filter is only called when the window manager desires to close the
application window.  If the event filter returns 1, then the window will
be closed, otherwise the window will remain open if possible.
If the quit event is generated by an interrupt signal, it will bypass the
internal queue and be delivered to the application at the next event poll.</P
><DIV
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><BLOCKQUOTE
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><P
><B
>Note: </B
>Events pushed onto the queue with <A
HREF="sdlpushevent.html"
><TT
CLASS="FUNCTION"
>SDL_PushEvent</TT
></A
> or <A
HREF="sdlpeepevents.html"
><TT
CLASS="FUNCTION"
>SDL_PeepEvents</TT
></A
> do not get passed through the event filter.</P
></BLOCKQUOTE
></DIV
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
><I
CLASS="EMPHASIS"
>Be Careful!</I
> The event filter function may run in a different thread so be careful what you do within it.</P
></BLOCKQUOTE
></DIV
></DIV
><DIV
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><A
NAME="AEN5214"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
></A
>,
<A
HREF="sdlgeteventfilter.html"
><TT
CLASS="FUNCTION"
>SDL_GetEventFilter</TT
></A
>,
<A
HREF="sdlpushevent.html"
><TT
CLASS="FUNCTION"
>SDL_PushEvent</TT
></A
></P
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