view docs/html/event.html @ 816:428f688f2ad2

Date: Fri, 13 Feb 2004 17:03:16 +0100 From: Max Horn Subject: Modifier key fix The internal modifier state can get out of sync with reality. To trigger this, do for example this: 1) Launch an SDL app 2) Alt-click on the desktop (this will hide the SDL app). 3) Bring the SDL app back to the front 4) SDL will still think alt is pressed (and as such will treat left clicks like middle clicks). If you press and release alt, it'll be fine again. The attached patch cures this by rechecking the modifier state whenever we process an event.
author Sam Lantinga <slouken@libsdl.org>
date Fri, 13 Feb 2004 17:57:16 +0000
parents 355632dca928
children
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>Chapter 8. Events</H1
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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
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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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> 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
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>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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