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Date: Thu, 28 Mar 2002 09:20:03 +0200 From: "Mike Gorchak" <mike@malva.ua> Subject: New QNX patch. Hi ! 1. Removed warning (possible bug) with invalid type, passing to the function in ph_WarpedMotion. 2. Rewritten handler of Ph_WM_RESIZE message, now works, but buggy (old handler doesn't work at all). 3. Added stub handler for Ph_WM_MAX (maximize) message. 4. Added more #ifdef HAVE_OPENGL to disable OpenGL stuff when it not needed. 5. Added support for SDL_NOFRAME and SDL_RESIZABLE flags (in OpenGL windows too). 6. Added cosmetic changes, if no SDL_RESIZABLE flag defined, disable resize handlers in window border and maximize button at caption. 7. Fixed my bug with invalid arguments count passed to PtCreateWidget call. 8. Fixed some palette problems. 9. Updated README.QNX file. And I changed testgl.c test application: 10. Added in testgl.c application support for SDL_NOFRAME flag and option -noframe.
author Sam Lantinga <slouken@libsdl.org>
date Thu, 28 Mar 2002 16:20:10 +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
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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
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><A
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></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
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><TT
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>SDL_PushEvent</TT
></A
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