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<HTML
><HEAD
><TITLE
>Events</TITLE
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>Chapter 8. Events</H1
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="event.html#AEN3691"
>Introduction</A
></DT
><DT
><A
HREF="eventstructures.html"
>SDL Event Structures.</A
></DT
><DT
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HREF="eventfunctions.html"
>Event Functions.</A
></DT
></DL
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><DIV
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><H1
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><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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