Mercurial > sdl-ios-xcode

<HTML
><HEAD
><TITLE
>SDL_JoystickGetAxis</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="Joystick"
HREF="joystick.html"><LINK
REL="PREVIOUS"
TITLE="SDL_JoystickUpdate"
HREF="sdljoystickupdate.html"><LINK
REL="NEXT"
TITLE="SDL_JoystickGetHat"
HREF="sdljoystickgethat.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="sdljoystickupdate.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
></TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="sdljoystickgethat.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><H1
><A
NAME="SDLJOYSTICKGETAXIS"
></A
>SDL_JoystickGetAxis</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN6320"
></A
><H2
>Name</H2
>SDL_JoystickGetAxis&nbsp;--&nbsp;Get the current state of an axis</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN6323"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN6324"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>Sint16 <B
CLASS="FSFUNC"
>SDL_JoystickGetAxis</B
></CODE
>(SDL_Joystick *joystick, int axis);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6330"
></A
><H2
>Description</H2
><P
><TT
CLASS="FUNCTION"
>SDL_JoystickGetAxis</TT
> returns the current state of the given <TT
CLASS="PARAMETER"
><I
>axis</I
></TT
> on the given <TT
CLASS="PARAMETER"
><I
>joystick</I
></TT
>.</P
><P
>On most modern joysticks the X axis is usually represented by <TT
CLASS="PARAMETER"
><I
>axis</I
></TT
> 0 and the Y axis by <TT
CLASS="PARAMETER"
><I
>axis</I
></TT
> 1. The value returned by <TT
CLASS="FUNCTION"
>SDL_JoystickGetAxis</TT
> is a signed integer (-32768 to 32768) representing the current position of the <TT
CLASS="PARAMETER"
><I
>axis</I
></TT
>, it maybe necessary to impose certain tolerances on these values to account for jitter. It is worth noting that some joysticks use axes 2 and 3 for extra buttons.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6341"
></A
><H2
>Return Value</H2
><P
>Returns a 16-bit signed integer representing the current position of the <TT
CLASS="PARAMETER"
><I
>axis</I
></TT
>.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6345"
></A
><H2
>Examples</H2
><P
><PRE
CLASS="PROGRAMLISTING"
>Sint16 x_move, y_move;
SDL_Joystick *joy1;
.
.
x_move=SDL_JoystickGetAxis(joy1, 0);
y_move=SDL_JoystickGetAxis(joy1, 1);</PRE
></P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6349"
></A
><H2
>See Also</H2
><P
><A
HREF="sdljoysticknumaxes.html"
><TT
CLASS="FUNCTION"
>SDL_JoystickNumAxes</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="sdljoystickupdate.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="sdljoystickgethat.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>SDL_JoystickUpdate</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="joystick.html"
ACCESSKEY="U"
>Up</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
>SDL_JoystickGetHat</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>
author	Sam Lantinga <slouken@libsdl.org>
date	Tue, 17 Feb 2009 05:39:18 +0000
parents	355632dca928
children