VR Transform Camera -
VRModules				               vr transform camera (6)


NAME
     vr transform camera - generate camera transformation events given
	a "vr device event" field.

SUMMARY
     Name	   VR Transform Camera

     Type	   mapper

     Inputs	   field float 1D 1-space uniform
		   (VR device event field)

     Outputs	   AVS Geometry


     Parameters	   _N_a_m_e		   _T_y_p_e		  _D_e_f_a_u_l_t	 _M_i_n	   _M_a_x
		   Focal Length	   float dial	  50		 1e-5	   1e5
		   Window Width	   float dial	  1		 .001	   1e3
		   Eye		   string	  <read only>
		   At		   string	  <read only>
		   Up		   string	  <read only>
		   Camera	   string	  "%camera1"
		   Reset	   boolean	  off		 off	   on

DESCRIPTION

	The VR Transform Camera module will take as input events from a
	VR input device, encoded into a "VR device event field" and generate
	camera transformation events.  These events are passed to the
	Geometry Viewer via the AVS Geometry data type.

INPUTS
     	field float 1D 1-space uniform - VR device event field.  A set
	of C-language macros is used internal to the code for this 
	module to encode the device event information into an AVS
	field.  This field is not readily processible (unfortunately)
	by "normal" AVS modules.  This is the case because both
	floating point and boolean values are encoded into the field data.


PARAMETERS

	Focal Length - sets the distance between the position of the
	viewer and the view reference point, or the "look-at" point.
	Normally, changing this value will have no visible effect unless
	the camera uses perspective projection (selectable from within
	the AVS Geometry Viewer).

	Window Width - sets the window half-width.  Increasing this
	value increases the Field of View of the camera.

	Reality Check parameters - these values are a reflection of the
	variables internal to this module, and are read-only.  They show
	the position of the viewer, the look-at point and the up vector.

	Camera Name - a string which names the camera which will be
	affected by the events produced in this module.  This has not
	been thoroughly tested.

	Reset - a boolean used to reset the eyepoint, etc., to startup
	defaults.  This is useful if you fly off into oblivion.

OUTPUT

	AVS Geometry - containing camera transformation commands.  Feed
	this to the geometry viewer.
	

EXAMPLE
	spaceball
	    |
	VR Xform Camera
            |
	Geoemtry Viewer

RELATED	MODULES
	VR Transform Camera, VR Transform Object, VR to acc floats,
	VR to floats, dummy device, VR print field.

BUGS
	You must use one "vr transform camera" module per camera.  In
	other words, you can't use a single module to control the position
	of multiple cameras.


VRModules					  Lawrence Berkeley Laboratory
