event.html
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>Chapter 8. Events</H1
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>Introduction</A
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>SDL Event Structures.</A
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>Event Functions.</A
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>Introduction</H1
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><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
>
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Internally, SDL stores all the events waiting to be handled in an event queue. Using functions like <A
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HREF="sdlpollevent.html"
><TT
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>SDL_PollEvent</TT
></A
> and <A
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><TT
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>SDL_PeepEvents</TT
></A
> you can observe and handle waiting input events.</P
><P
>The key to event handling in SDL is the <A
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><SPAN
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>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
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>SDL_PollEvent</TT
> function and it is then up to the application to process the information stored with them.</P
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