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joystick_getaxis(3)	       Svgalib User Manual	     joystick_getaxis(3)

NAME
     joystick_getaxis,	joystick_getbutton  -  query the current state of a joy-
     stick.

SYNOPSIS
     #include <vgajoystick.h>

     char joystick_getaxis(int joydev, int a);
     char joystick_getbutton(int joydev, int b);

DESCRIPTION
     These functions query the current state of the joystick  joydev.	Actually
     this is the state found during the last call to joystick_update(3) with the
     default joystick event handler active.

     joystick_getaxis(joydev,  a)  return  the	current  state of the given axis
     (usually it is x - 0, y - 1, z - 1, ...)  in range -128 .. 127.   Some  ef-
     fort is made such that the center position is close to 0.

     Note  that especially the version 0.* protocol joystick calibration is very
     bad. You won't usually see the extrem values on the extreme position. Also,
     the center position will be close to zero but often not be exactly zero and
     return values will also vary slightly from call to call even when the  user
     did not move the joystick.

     joystick_getbutton(joydev,  b)  returns the state of a button. It returns 1
     for pressed button and 0 else. Note that  no  hardware  checks  for  button
     clicks.  The  button  press  is only detected during a call to joystick_up-
     date(3) (at least in the 0.* protocol).

     NOTE: The functions simply return the data passed to the  default	joystick
     event handler!

     For  your convenience, the following stortcuts have been established by use
     of the preprocessor:

	    joystick_button1(i) for joystick_getbutton(i, 0).
	    joystick_button2(i) for joystick_getbutton(i, 1).
	    joystick_button3(i) for joystick_getbutton(i, 2).
	    joystick_button4(i) for joystick_getbutton(i, 3).

	    joystick_x(i) for joystick_getaxis(i, 0).
	    joystick_y(i) for joystick_getaxis(i, 1).
	    joystick_z(i) for joystick_getaxis(i, 2).

	    joystick_getb1() for joystick_getbutton(0, 0).
	    joystick_getb2() for joystick_getbutton(0, 1).
	    joystick_getb3() for joystick_getbutton(0, 2).
	    joystick_getb4() for joystick_getbutton(0, 3).

	    joystick_getx() for joystick_getaxis(0, 0).
	    joystick_gety() for joystick_getaxis(0, 1).
	    joystick_getz() for joystick_getaxis(0, 2).

CAVEATS
     This function is only available in ELF versions of svgalib.  Due  to  back-
     wards compatibility issues it cannot be used with shared a.out libs.

SEE ALSO
     svgalib(7),   vgagl(7),  libvga.config(5),  joytest(6),  mjoytest(6),  joy-
     stick_init(3),	 joystick_close(3),	  joystick_update(3),	    joy-
     stick_sethandler(3), joystick_setdefaulthandler(3), joystick_getnumaxes(3),
     joystick_getnumbuttons(3).

AUTHOR
     The   svgalib  joystick  handler  was  mostly  done  by  Daniel  Engstr\"om
     <daniel.engstrom@riksnett.no>.  Multiple joystick, VC switching support and
     code to glue it into svgalib  by  Michael	Weller	<eowmob@exp-math.uni-es-
     sen.de>.  Part  of  the  code  is	based  on code from C. Smith and Vojtech
     Pavlik.

Svgalib 1.3.0			  14 April 1998 	     joystick_getaxis(3)

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