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More general fix for bug #189 The clipping is done at a higher level, and the low level functions are passed clipped rectangles. Drivers which don't support source clipping have not been changed, so the image will be squished instead of clipped, but at least they will no longer crash when the destination rect was out of bounds.
author Sam Lantinga <slouken@libsdl.org>
date Mon, 17 Apr 2006 06:47:23 +0000
parents 355632dca928
children
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<HTML
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>Events</TITLE
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>Chapter 8. Events</H1
><DIV
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><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="event.html#AEN3691"
>Introduction</A
></DT
><DT
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>SDL Event Structures.</A
></DT
><DT
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>Event Functions.</A
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>Introduction</H1
><P
>Event handling allows your application to receive input from the user. Event handling is initalised (along with video) with a call to:
<PRE
CLASS="PROGRAMLISTING"
>SDL_Init(SDL_INIT_VIDEO);</PRE
>
Internally, SDL stores all the events waiting to be handled in an event queue. Using functions like <A
HREF="sdlpollevent.html"
><TT
CLASS="FUNCTION"
>SDL_PollEvent</TT
></A
> and <A
HREF="sdlpeepevents.html"
><TT
CLASS="FUNCTION"
>SDL_PeepEvents</TT
></A
> you can observe and handle waiting input events.</P
><P
>The key to event handling in SDL is the <A
HREF="sdlevent.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
></A
> union. The event queue itself is composed of a series of <SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
> unions, one for each waiting event. <SPAN
CLASS="STRUCTNAME"
>SDL_Event</SPAN
> unions are read from the queue with the <TT
CLASS="FUNCTION"
>SDL_PollEvent</TT
> function and it is then up to the application to process the information stored with them.</P
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