diff docs/html/sdladdtimer.html @ 0:74212992fb08

Initial revision
author Sam Lantinga <slouken@lokigames.com>
date Thu, 26 Apr 2001 16:45:43 +0000
parents
children 55f1f1b3e27d
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/docs/html/sdladdtimer.html	Thu Apr 26 16:45:43 2001 +0000
@@ -0,0 +1,275 @@
+<HTML
+><HEAD
+><TITLE
+>SDL_AddTimer</TITLE
+><META
+NAME="GENERATOR"
+CONTENT="Modular DocBook HTML Stylesheet Version 1.61
+"><LINK
+REL="HOME"
+TITLE="SDL Library Documentation"
+HREF="index.html"><LINK
+REL="UP"
+TITLE="Time"
+HREF="time.html"><LINK
+REL="PREVIOUS"
+TITLE="SDL_Delay"
+HREF="sdldelay.html"><LINK
+REL="NEXT"
+TITLE="SDL_RemoveTimer"
+HREF="sdlremovetimer.html"></HEAD
+><BODY
+CLASS="REFENTRY"
+BGCOLOR="#FFF8DC"
+TEXT="#000000"
+LINK="#0000ee"
+VLINK="#551a8b"
+ALINK="#ff0000"
+><DIV
+CLASS="NAVHEADER"
+><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="sdldelay.html"
+>Prev</A
+></TD
+><TD
+WIDTH="80%"
+ALIGN="center"
+VALIGN="bottom"
+></TD
+><TD
+WIDTH="10%"
+ALIGN="right"
+VALIGN="bottom"
+><A
+HREF="sdlremovetimer.html"
+>Next</A
+></TD
+></TR
+></TABLE
+><HR
+ALIGN="LEFT"
+WIDTH="100%"></DIV
+><H1
+><A
+NAME="SDLADDTIMER"
+>SDL_AddTimer</A
+></H1
+><DIV
+CLASS="REFNAMEDIV"
+><A
+NAME="AEN7854"
+></A
+><H2
+>Name</H2
+>SDL_AddTimer&nbsp;--&nbsp;Add a timer which will call a callback after the specified number of milliseconds has
+elapsed.</DIV
+><DIV
+CLASS="REFSYNOPSISDIV"
+><A
+NAME="AEN7857"
+></A
+><H2
+>Synopsis</H2
+><DIV
+CLASS="FUNCSYNOPSIS"
+><A
+NAME="AEN7858"
+></A
+><P
+></P
+><PRE
+CLASS="FUNCSYNOPSISINFO"
+>#include "SDL.h"</PRE
+><P
+><CODE
+><CODE
+CLASS="FUNCDEF"
+>SDL_TimerID <B
+CLASS="FSFUNC"
+>SDL_AddTimer</B
+></CODE
+>(Uint32 interval, SDL_NewTimerCallback callback, void *param);</CODE
+></P
+><P
+></P
+></DIV
+></DIV
+><DIV
+CLASS="REFSECT1"
+><A
+NAME="SDLNEWTIMERCALLBACK"
+></A
+><H2
+>Callback</H2
+><PRE
+CLASS="PROGRAMLISTING"
+>/* type definition for the "new" timer callback function */
+typedef Uint32 (*SDL_NewTimerCallback)(Uint32 interval, void *param);</PRE
+></DIV
+><DIV
+CLASS="REFSECT1"
+><A
+NAME="AEN7867"
+></A
+><H2
+>Description</H2
+><P
+>Adds a callback function to be run after the specified number of
+milliseconds has elapsed. The callback function is passed the current
+timer interval and the user supplied parameter from the
+<TT
+CLASS="FUNCTION"
+>SDL_AddTimer</TT
+> call and returns the next timer
+interval. If the returned value from the callback is the same as the one
+passed in, the periodic alarm continues, otherwise a new alarm is
+scheduled.</P
+><P
+>To cancel a currently running timer call
+<A
+HREF="sdlremovetimer.html"
+>SDL_RemoveTimer</A
+> with the
+timer ID returned from
+<TT
+CLASS="FUNCTION"
+>SDL_AddTimer</TT
+>.</P
+><P
+>The timer callback function may run in a different thread than your
+main program, and so shouldn't call any functions from within itself.</P
+><P
+>The maximum resolution of this timer is 10 ms, which means that if
+you request a 16 ms timer, your callback will run approximately 20 ms
+later on an unloaded system.  If you wanted to set a flag signaling
+a frame update at 30 frames per second (every 33 ms), you might set a
+timer for 30 ms (see example below).
+
+If you use this function, you need to pass <TT
+CLASS="LITERAL"
+>SDL_INIT_TIMER</TT
+>
+to <A
+HREF="sdlinit.html"
+>SDL_Init</A
+>.</P
+></DIV
+><DIV
+CLASS="REFSECT1"
+><A
+NAME="AEN7878"
+></A
+><H2
+>Return Value</H2
+><P
+>Returns an ID value for the added timer or
+<SPAN
+CLASS="RETURNVALUE"
+>NULL</SPAN
+> if there was an error.</P
+></DIV
+><DIV
+CLASS="REFSECT1"
+><A
+NAME="AEN7882"
+></A
+><H2
+>Examples</H2
+><P
+><PRE
+CLASS="PROGRAMLISTING"
+>my_timer_id = SDL_AddTimer((33/10)*10, my_callbackfunc, my_callback_param);</PRE
+></P
+></DIV
+><DIV
+CLASS="REFSECT1"
+><A
+NAME="AEN7886"
+></A
+><H2
+>See Also</H2
+><P
+><A
+HREF="sdlremovetimer.html"
+><TT
+CLASS="FUNCTION"
+>SDL_RemoveTimer</TT
+></A
+></P
+></DIV
+><DIV
+CLASS="NAVFOOTER"
+><HR
+ALIGN="LEFT"
+WIDTH="100%"><TABLE
+WIDTH="100%"
+BORDER="0"
+CELLPADDING="0"
+CELLSPACING="0"
+><TR
+><TD
+WIDTH="33%"
+ALIGN="left"
+VALIGN="top"
+><A
+HREF="sdldelay.html"
+>Prev</A
+></TD
+><TD
+WIDTH="34%"
+ALIGN="center"
+VALIGN="top"
+><A
+HREF="index.html"
+>Home</A
+></TD
+><TD
+WIDTH="33%"
+ALIGN="right"
+VALIGN="top"
+><A
+HREF="sdlremovetimer.html"
+>Next</A
+></TD
+></TR
+><TR
+><TD
+WIDTH="33%"
+ALIGN="left"
+VALIGN="top"
+>SDL_Delay</TD
+><TD
+WIDTH="34%"
+ALIGN="center"
+VALIGN="top"
+><A
+HREF="time.html"
+>Up</A
+></TD
+><TD
+WIDTH="33%"
+ALIGN="right"
+VALIGN="top"
+>SDL_RemoveTimer</TD
+></TR
+></TABLE
+></DIV
+></BODY
+></HTML
+>
\ No newline at end of file