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event.html
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event.html
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<HTML
><HEAD
><TITLE
>Events</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.64
"><LINK
REL="HOME"
TITLE="SDL Library Documentation"
HREF="index.html"><LINK
REL="UP"
TITLE="SDL Reference"
HREF="reference.html"><LINK
REL="PREVIOUS"
TITLE="SDL_WM_GrabInput"
HREF="sdlwmgrabinput.html"><LINK
REL="NEXT"
TITLE="SDL Event Structures."
HREF="eventstructures.html"><META
NAME="KEYWORD"
CONTENT="events"><META
NAME="KEYWORD"
CONTENT="function"></HEAD
><BODY
CLASS="CHAPTER"
BGCOLOR="#FFF8DC"
TEXT="#000000"
LINK="#0000ee"
VLINK="#551a8b"
ALINK="#ff0000"
><DIV
CLASS="NAVHEADER"
><TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
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>SDL Library Documentation</TH
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><TR
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ALIGN="left"
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><A
HREF="sdlwmgrabinput.html"
>Prev</A
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>Next</A
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><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><DIV
CLASS="CHAPTER"
><H1
><A
NAME="EVENT"
>Chapter 8. Events</A
></H1
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="event.html#AEN3307"
>Introduction</A
></DT
><DT
><A
HREF="eventstructures.html"
>SDL Event Structures.</A
></DT
><DT
><A
HREF="eventfunctions.html"
>Event Functions.</A
></DT
></DL
></DIV
><DIV
CLASS="SECT1"
><H1
CLASS="SECT1"
><A
NAME="AEN3307"
>Introduction</A
></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
></DIV
></DIV
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>SDL Event Structures.</TD
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>