| <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 |
| > |