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Updated copyright information for 2002
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 06 Mar 2002 11:23:08 +0000 |
parents | e5bc29de3f0a |
children | 355632dca928 |
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<HTML ><HEAD ><TITLE >SDL_JoystickGetBall</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.64 "><LINK REL="HOME" TITLE="SDL Library Documentation" HREF="index.html"><LINK REL="UP" TITLE="Joystick" HREF="joystick.html"><LINK REL="PREVIOUS" TITLE="SDL_JoystickGetButton" HREF="sdljoystickgetbutton.html"><LINK REL="NEXT" TITLE="SDL_JoystickClose" HREF="sdljoystickclose.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="sdljoystickgetbutton.html" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdljoystickclose.html" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLJOYSTICKGETBALL" >SDL_JoystickGetBall</A ></H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN6045" ></A ><H2 >Name</H2 >SDL_JoystickGetBall -- Get relative trackball motion</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN6048" ></A ><H2 >Synopsis</H2 ><DIV CLASS="FUNCSYNOPSIS" ><A NAME="AEN6049" ></A ><P ></P ><PRE CLASS="FUNCSYNOPSISINFO" >#include "SDL.h"</PRE ><P ><CODE ><CODE CLASS="FUNCDEF" >int <B CLASS="FSFUNC" >SDL_JoystickGetBall</B ></CODE >(SDL_Joystick *joystick, int ball, int *dx, int *dy);</CODE ></P ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6055" ></A ><H2 >Description</H2 ><P >Get the <TT CLASS="PARAMETER" ><I >ball</I ></TT > axis change.</P ><P >Trackballs can only return relative motion since the last call to <TT CLASS="FUNCTION" >SDL_JoystickGetBall</TT >, these motion deltas a placed into <TT CLASS="PARAMETER" ><I >dx</I ></TT > and <TT CLASS="PARAMETER" ><I >dy</I ></TT >.</P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6063" ></A ><H2 >Return Value</H2 ><P >Returns <SPAN CLASS="RETURNVALUE" >0</SPAN > on success or <SPAN CLASS="RETURNVALUE" >-1</SPAN > on failure</P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6068" ></A ><H2 >Examples</H2 ><P ><PRE CLASS="PROGRAMLISTING" >int delta_x, delta_y; SDL_Joystick *joy; . . . SDL_JoystickUpdate(); if(SDL_JoystickGetBall(joy, 0, &delta_x, &delta_y)==-1) printf("TrackBall Read Error!\n"); printf("Trackball Delta- X:%d, Y:%d\n", delta_x, delta_y);</PRE ></P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6072" ></A ><H2 >See Also</H2 ><P ><A HREF="sdljoysticknumballs.html" ><TT CLASS="FUNCTION" >SDL_JoystickNumBalls</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="sdljoystickgetbutton.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="sdljoystickclose.html" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_JoystickGetButton</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="joystick.html" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_JoystickClose</TD ></TR ></TABLE ></DIV ></BODY ></HTML >