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Emphasized the separation between SDL_Surface and SDL_Texture - SDL_Surface is a system memory representation of pixel data - SDL_Texture is a video memory representation of pixel data The concept of SDL_Surface with SDL_HWSURFACE is no longer used. Separated SDL_Texture types by usage rather than memory type - SDL_TEXTUREACCESS_STATIC is for rarely changed pixel data, can be placed in video memory. - SDL_TEXTUREACCESS_STREAMING is for frequently changing pixel data, usually placed in system memory or AGP memory. Optimized the SDL_compat usage of the OpenGL renderer by only using one copy of the framebuffer instead of two.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 11 Aug 2007 20:54:31 +0000
parents 355632dca928
children
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>SDL_SetEventFilter</TITLE
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><H1
><A
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>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"
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><H2
>Synopsis</H2
><DIV
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><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
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><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
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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
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><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
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><A
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></A
><H2
>See Also</H2
><P
><A
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><SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
></A
>,
<A
HREF="sdlgeteventfilter.html"
><TT
CLASS="FUNCTION"
>SDL_GetEventFilter</TT
></A
>,
<A
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><TT
CLASS="FUNCTION"
>SDL_PushEvent</TT
></A
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