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view docs/html/sdlsettimer.html @ 1585:980d2a0dc2a3
Date: Tue, 4 Mar 2003 15:05:31 -0800
From: "Jim"
Subject: [SDL] Frame Buffer patches...
Okay I'm new at patch generation - so please tell me if there's a better way
I could have done this.
Attached are two patch files generated with 'cvs diff -u'
SDL-fb-open-lock.patch applies to SDL_fbvideo.c
Modifies the open loop to check /dev/fb/0 found on devfs...
Modifies the lock code to return failure if the current virtual terminal
is not the one opened for frame buffer writing...
Lock would hang forever if switched away (ctrl-alt-F1) ...
SDL-fb-mousedrv-screensave.patch applies to SDL_fbevents.c
Switches default mouse mode based on SDL_MOUSEDRV - currently only
accepts PS2 - otherwise default is MS Mouse.
When the screen is switched - exisiting code (wrapped in ifdef
SAVE_SCREEN_COTENTS) would save the wrong bit of the screen....
( I run frame buffer 1600x1200, the size I requested was 800x600 - the
save would save the top 800 lines (non biased) and restore them... Adding
screen->offset fixed that )
However, if that option is not set, then a call to SDL_UpdateRect (full
screen) is made. (which may have had it's contents changed since the screen
is not entirely locked because of lock-failure patch)
Jim
[patches slightly tweaked for SDL 1.2.10]
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 22 Mar 2006 07:48:22 +0000 |
parents | 355632dca928 |
children |
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<HTML ><HEAD ><TITLE >SDL_SetTimer</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="Time" HREF="time.html"><LINK REL="PREVIOUS" TITLE="SDL_RemoveTimer" HREF="sdlremovetimer.html"></HEAD ><BODY CLASS="REFENTRY" 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="sdlremovetimer.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" > </TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLSETTIMER" ></A >SDL_SetTimer</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN8557" ></A ><H2 >Name</H2 >SDL_SetTimer -- Set a callback to run after the specified number of milliseconds has elapsed.</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN8560" ></A ><H2 >Synopsis</H2 ><DIV CLASS="FUNCSYNOPSIS" ><A NAME="AEN8561" ></A ><P ></P ><PRE CLASS="FUNCSYNOPSISINFO" >#include "SDL.h"</PRE ><P ><CODE ><CODE CLASS="FUNCDEF" >int <B CLASS="FSFUNC" >SDL_SetTimer</B ></CODE >(Uint32 interval, SDL_TimerCallback callback);</CODE ></P ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="SDLTIMERCALLBACK" ></A ><H2 >Callback</H2 ><P >/* Function prototype for the timer callback function */ typedef Uint32 (*SDL_TimerCallback)(Uint32 interval);</P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN8570" ></A ><H2 >Description</H2 ><P >Set a callback to run after the specified number of milliseconds has elapsed. The callback function is passed the current timer interval and returns the next timer interval. If the returned value 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 <TT CLASS="FUNCTION" >SDL_SetTimer(0, NULL);</TT ></P ><P >The timer callback function may run in a different thread than your main constant, 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).</P ><P >If you use this function, you need to pass <TT CLASS="LITERAL" >SDL_INIT_TIMER</TT > to <TT CLASS="FUNCTION" >SDL_Init()</TT >.</P ><DIV CLASS="NOTE" ><BLOCKQUOTE CLASS="NOTE" ><P ><B >Note: </B >This function is kept for compatibility but has been superseded by the new timer functions <A HREF="sdladdtimer.html" >SDL_AddTimer</A > and <A HREF="sdlremovetimer.html" >SDL_RemoveTimer</A > which support multiple timers.</P ></BLOCKQUOTE ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN8584" ></A ><H2 >Examples</H2 ><P ><PRE CLASS="PROGRAMLISTING" >SDL_SetTimer((33/10)*10, my_callback);</PRE ></P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN8588" ></A ><H2 >See Also</H2 ><P ><A HREF="sdladdtimer.html" ><TT CLASS="FUNCTION" >SDL_AddTimer</TT ></A ></P ></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="sdlremovetimer.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" > </TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_RemoveTimer</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="time.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" > </TD ></TR ></TABLE ></DIV ></BODY ></HTML >