208 lines
3.0 KiB
HTML
208 lines
3.0 KiB
HTML
<HTML
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><HEAD
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><TITLE
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>Events</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.64
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"><LINK
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REL="HOME"
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TITLE="SDL Library Documentation"
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HREF="index.html"><LINK
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REL="UP"
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TITLE="SDL Reference"
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HREF="reference.html"><LINK
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REL="PREVIOUS"
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TITLE="SDL_WM_GrabInput"
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HREF="sdlwmgrabinput.html"><LINK
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REL="NEXT"
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TITLE="SDL Event Structures."
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HREF="eventstructures.html"><META
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NAME="KEYWORD"
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CONTENT="events"><META
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NAME="KEYWORD"
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CONTENT="function"></HEAD
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><BODY
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CLASS="CHAPTER"
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BGCOLOR="#FFF8DC"
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TEXT="#000000"
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LINK="#0000ee"
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VLINK="#551a8b"
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ALINK="#ff0000"
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><DIV
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CLASS="NAVHEADER"
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><TABLE
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CELLSPACING="0"
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><TR
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><TH
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COLSPAN="3"
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ALIGN="center"
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>SDL Library Documentation</TH
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></TR
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><TR
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><TD
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WIDTH="10%"
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ALIGN="left"
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VALIGN="bottom"
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><A
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HREF="sdlwmgrabinput.html"
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>Prev</A
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></TD
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><TD
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WIDTH="80%"
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></TD
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><TD
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WIDTH="10%"
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ALIGN="right"
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VALIGN="bottom"
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><A
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HREF="eventstructures.html"
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>Next</A
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></TD
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></TR
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></TABLE
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><HR
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="CHAPTER"
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><H1
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><A
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NAME="EVENT"
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>Chapter 8. Events</A
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></H1
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><DIV
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CLASS="TOC"
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><DL
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><DT
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><B
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>Table of Contents</B
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></DT
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><DT
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><A
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HREF="event.html#AEN3269"
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>Introduction</A
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></DT
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><DT
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><A
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HREF="eventstructures.html"
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>SDL Event Structures.</A
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></DT
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><DT
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><A
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HREF="eventfunctions.html"
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>Event Functions.</A
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></DT
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></DL
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></DIV
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><DIV
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CLASS="SECT1"
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><H1
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CLASS="SECT1"
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><A
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NAME="AEN3269"
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>Introduction</A
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></H1
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><P
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>Event handling allows your application to receive input from the user. Event handling is initalised (along with video) with a call to:
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<PRE
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CLASS="PROGRAMLISTING"
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>SDL_Init(SDL_INIT_VIDEO);</PRE
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>
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Interally, SDL stores all the events waiting to be handled in an event queue. Using functions like <A
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HREF="sdlpollevent.html"
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><TT
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CLASS="FUNCTION"
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>SDL_PollEvent</TT
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></A
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> and <A
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HREF="sdlpeepevents.html"
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><TT
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CLASS="FUNCTION"
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>SDL_PeepEvents</TT
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></A
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> you can observe and handle waiting input events.</P
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><P
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>The key to event handling in SDL is the <A
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HREF="sdlevent.html"
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><SPAN
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CLASS="STRUCTNAME"
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>SDL_Event</SPAN
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></A
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> union. The event queue itself is composed of a series of <SPAN
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CLASS="STRUCTNAME"
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>SDL_Event</SPAN
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> unions, one for each waiting event. <SPAN
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CLASS="STRUCTNAME"
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>SDL_Event</SPAN
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> unions are read from the queue with the <TT
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CLASS="FUNCTION"
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>SDL_PollEvent</TT
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> function and it is then up to the application to process the information stored with them.</P
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></DIV
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></DIV
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><DIV
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CLASS="NAVFOOTER"
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><HR
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ALIGN="LEFT"
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WIDTH="100%"><TABLE
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WIDTH="100%"
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><TR
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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><A
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HREF="sdlwmgrabinput.html"
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>Prev</A
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></TD
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
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><A
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HREF="index.html"
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>Home</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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><A
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HREF="eventstructures.html"
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>Next</A
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></TD
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></TR
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><TR
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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>SDL_WM_GrabInput</TD
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
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><A
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HREF="reference.html"
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>Up</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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>SDL Event Structures.</TD
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></TR
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></TABLE
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></DIV
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></BODY
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></HTML
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> |