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Date: Sat, 14 Feb 2004 14:52:40 +0200 From: "Mike Gorchak" Subject: Batch of the QNX6 fixes for the SDL 1. Updated readme.QNX 2. Fixed crashes during intensive window updating under fast machines (got over 200 rectangles for update). 3. Fixed double-buffered fullscreen modes, now it works as needed. 4. Fixed Photon detection algorithm. 5. Fixed HWSURFACE update function. 6. Added SDL_PHOTON_FULLSCREEN_REFRESH environment variable support for control refresh rates under Photon. 7. Added 640x400 fullscreen mode emulation via 640x480 (if videodriver not supports original 640x400 mode of course) shifted by 40 vertical pixels from begin, to center it. It's needed for some old DOS games which ran in doubled 320x200 mode. 8. Added available video ram amount support. 8. Added hardware surface allocation/deallocation support if current videomode and videodriver supports it. 9. Added hardware filling support. 10. Added hardware blits support (simple and colorkeyed). And I've added to testvidinfo test color-keyed blits benchmark (maybe need to add alpha blits benchmark too ?). Currently Photon not supporting any alpha hardware blittings (all drivers lack of alpha blitting code support, only software alpha blitting exist in photon, which is hundreds times slowest than the SDL's one). So I've not added the alpha support. I suppose new QNX 6.3 will have the hardware alpha support, so when it will be done, I'll add alpha support.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 14 Feb 2004 20:22:21 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>SDL_SetEventFilter</TITLE
><META
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><H1
><A
NAME="SDLSETEVENTFILTER"
></A
>SDL_SetEventFilter</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN5575"
></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="AEN5578"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN5579"
></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="AEN5585"
></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
><SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Be Careful!</I
></SPAN
> 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="AEN5602"
></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
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