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joystick_getaxis(3)	      Svgalib User Manual	   joystick_getaxis(3)

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

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.	 Actu-
       ally 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
       effort 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	 posi-
       tion.  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 but-
       ton clicks. The button press is only detected during  a	call  to  joy-
       stick_update(3) (at least in the	0.* protocol).

       NOTE:  The  functions simply return the data passed to the default joy-
       stick 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
       backwards 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_getnu-
       maxes(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-essen.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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