view docs/html/event.html @ 1614:6162b8d921ce

Date: Wed, 29 Mar 2006 17:26:55 +0200 CEST From: "Fran���is Revol" Subject: [SDL] BeOS port fix: PrintScreen key crashing It seems the latest SDL crashes when someone hits the PrtScrn key in ZETA (BeOS R6), somewhere it gets a negative value as key code (or a big unsigned maybe ?), and uses it as an index in the keysym table... I'll investigate the cause for the negative value, but it's always better to check for bounds correctly when indexing a table. The attached diff fixes it. Fran���is Revol -- Software Architect yellowTAB GmbH
author Sam Lantinga <slouken@libsdl.org>
date Fri, 31 Mar 2006 06:16:20 +0000
parents 355632dca928
children
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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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>Introduction</H1
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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:
<PRE
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>SDL_Init(SDL_INIT_VIDEO);</PRE
>
Internally, SDL stores all the events waiting to be handled in an event queue. Using functions like <A
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><TT
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>SDL_PollEvent</TT
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> and <A
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>SDL_PeepEvents</TT
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> you can observe and handle waiting input events.</P
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>The key to event handling in SDL is the <A
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>SDL_Event</SPAN
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> union. The event queue itself is composed of a series of <SPAN
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>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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