0,0 → 1,254 |
<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="AEN5886" |
></A |
><H2 |
>Name</H2 |
>SDL_JoystickGetBall -- Get relative trackball motion</DIV |
><DIV |
CLASS="REFSYNOPSISDIV" |
><A |
NAME="AEN5889" |
></A |
><H2 |
>Synopsis</H2 |
><DIV |
CLASS="FUNCSYNOPSIS" |
><A |
NAME="AEN5890" |
></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="AEN5896" |
></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="AEN5904" |
></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="AEN5909" |
></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="AEN5913" |
></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 |
> |