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HandleEvent() returns done each time it is called. If done was set to 0 the program should quit, but because done is not checked until *all* events are handled a
following event can reset done to 1 and prevent the program from terminating when told to. I fixed the while loop that handles events to check for the state of done
after handling each event. That could leave some events unhandled when the program exits, but it ensures that the program will exit.
author | Bob Pendleton <bob@pendleton.com> |
---|---|
date | Wed, 20 Feb 2008 23:27:33 +0000 |
parents | 355632dca928 |
children |
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<HTML ><HEAD ><TITLE >Time Examples</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ "><LINK REL="HOME" TITLE="SDL Library Documentation" HREF="index.html"><LINK REL="UP" TITLE="Examples" HREF="guideexamples.html"><LINK REL="PREVIOUS" TITLE="CDROM Examples" HREF="guidecdromexamples.html"><LINK REL="NEXT" TITLE="SDL Reference" HREF="reference.html"></HEAD ><BODY CLASS="SECT1" BGCOLOR="#FFF8DC" TEXT="#000000" LINK="#0000ee" VLINK="#551a8b" ALINK="#ff0000" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >SDL Library Documentation</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="guidecdromexamples.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" >Chapter 4. Examples</TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="reference.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECT1" ><H1 CLASS="SECT1" ><A NAME="GUIDETIMEEXAMPLES" ></A >Time Examples</H1 ><P ></P ><DIV CLASS="SECT2" ><H2 CLASS="SECT2" ><A NAME="AEN412" ></A >Time based game loop</H2 ><P ><PRE CLASS="PROGRAMLISTING" >#define TICK_INTERVAL 30 static Uint32 next_time; Uint32 time_left(void) { Uint32 now; now = SDL_GetTicks(); if(next_time <= now) return 0; else return next_time - now; } /* main game loop */ next_time = SDL_GetTicks() + TICK_INTERVAL; while ( game_running ) { update_game_state(); SDL_Delay(time_left()); next_time += TICK_INTERVAL; } </PRE ></P ></DIV ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="guidecdromexamples.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="reference.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >CDROM Examples</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="guideexamples.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL Reference</TD ></TR ></TABLE ></DIV ></BODY ></HTML >