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>SDL_JoystickGetAxis</H1
><DIV
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><H2
>Name</H2
>SDL_JoystickGetAxis&nbsp;--&nbsp;Get the current state of an axis</DIV
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>Synopsis</H2
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><PRE
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>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>Sint16 <B
CLASS="FSFUNC"
>SDL_JoystickGetAxis</B
></CODE
>(SDL_Joystick *joystick, int axis);</CODE
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><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
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><A
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></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
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><A
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><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
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><H2
>See Also</H2
><P
><A
HREF="sdljoysticknumaxes.html"
><TT
CLASS="FUNCTION"
>SDL_JoystickNumAxes</TT
></A
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author	Sam Lantinga <slouken@libsdl.org>
date	Mon, 13 Apr 2009 08:44:48 +0000
parents	355632dca928
children