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Date: Mon, 3 May 2004 03:15:01 +0100 From: David Symmonds Subject: SDL Typedef Structs Hi, Thanks for the SDL libraries, I have been using them for about a year now and they are really brilliant. One thing that I have just found whilst using them through C++ (and needing forward declarations) is that when you typedef structs you sometimes use typedef struct Name { ... }Name; e.g. SDL_Surface and other times use typedef struct { ... }Name; e.g. SDL_Rect The first type works fine, when I define a header file I can just put 'struct Name;' at the top and use the Name throughout. However, the second type is harder to use in a header, and I haven't found a way yet, other than to include 'SDL.h' in the header file (undesirable). Would there be any harm in changing the definition of SDL_Rect and such like to the second form?
author Sam Lantinga <slouken@libsdl.org>
date Sun, 18 Jul 2004 22:57:40 +0000
parents 355632dca928
children
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<HTML
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>Events</TITLE
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>Chapter 8. Events</H1
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>Table of Contents</B
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><DT
><A
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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
><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
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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
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
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