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Date: Mon, 28 Jul 2003 18:30:50 +0300 From: "Mike Gorchak" Subject: New test for overlays While writting QNX Photon Overlay code I've found that the existent overlay test application is not enough, it performs too artificial tests - it always moves/resizes the overlay's viewport, but in the real life that happens very rare. So I decided to write new test (commonly base on testoverlay.c code) and called it testoverlay2 :) moose.dat - raw 8 bit paletted data of the small movie. (It was a moose.gif, also included in the attachment as reference, but not needed for this test, it is just for information). I cannot find, who created this .gif, so no credits this time :) But over inet I saw this gif zillion times, so I think we do not infringing somebody rights :)
author Sam Lantinga <slouken@libsdl.org>
date Fri, 08 Aug 2003 21:31:18 +0000
parents e5bc29de3f0a
children 355632dca928
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<HTML
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><TITLE
>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
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><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
CLASS="REFSECT1"
><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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