The following is the format of fig output (fig 2.1).

(1) The very first line is a comment line containing the name and version:
	#FIG 2.1

    The character # at the first column of a line indicates that the line
    is a comment line which will be ignored.

(2) The first non-comment line consists of two numbers :

	int	fig_resolution		(pixels/inch)
	int	coordinate_system	(1 : origin is at the lower left corner
					 2 : Upper left)

    Fig_resolution is the resolution fig is using for the current file.
    It must always be 80 for compatibility with this version of Fig.
    Pixels are assumed to be square.

(3) The rest of the file contains various objects.  An object can be one
    of six classes (or types).

	  i)	Arc.
	 ii)	Ellipse which is a generalization of circle.
	iii)	Polyline which includes polygon and box.
	 iv)	Spline which includes closed/open control/interpolated spline.
	  v)	Text.
	 vi)	Compound object which is composed of one or more objects.

    In the following elaboration on object formats, every value of fig
    output are separated by blank characters or new line ('\n').  The
    value of the not-used parameters will be -1.

    Some fields are described as "enumeration type" or "bit vector"; the 
    values which these fields can take are defined in the header file object.h.
    The pen, color, arrow_type, and arrow_style fields are described as unused.
    These values may be defined in some future version of Fig.

    (3.1) ARC

    First line :
	type	name			(brief description)
	----	----			-------------------
	int	object_code		(always 5)
	int	sub_type		(always	1)
	int	line_style		(enumeration type)
	int	line_thickness		(pixels)
	int	color			(not used)
	int	depth			(no units)
	int	pen			(not used)
	int	area_fill		(enumeration type)
	float	style_val		(pixels)
	int	direction		(0 : clockwise, 1 : counterclockwise)
	int	forward_arrow		(0: no forward arrow, 1: on)
	int	backward_arrow		(0: no forward arrow, 1: on)
	float	center_x, center_y	(center of the arc)
	int	x1, y1			(pixels, the 1st point the user entered)
	int	x2, y2			(pixels, the 2nd point)
	int	x3, y3			(pixels, the last point)

    Forward arrow line (Optional; absent if forward_arrow is 0) :
	type	name			(brief description)
	----	----			-------------------
	int	arrow_type		(not used)
	int	arrow_style		(not used)
	float	arrow_thickness		(pixels)
	float 	arrow_width		(pixels)
	float	arrow_height		(pixels)

    Backward arrow line (Optional; absent if backward_arrow is 0) :
	type	name			(brief description)
	----	----			-------------------
	int	arrow_type		(not used)
	int	arrow_style		(not used)
	float	arrow_thickness		(pixels)
	float	arrow_width		(pixels)
	float	arrow_height		(pixels)

    (3.2) COMPOUND

    A line with object code 6 signifies the start of a compound.
    There are four more numbers on this line which indicate the
    upper right corner and the lower left corner of the bounding
    box of this compound.  A line with object code -6 signifies
    the end of the compound.  Compound may be nested.

    First line :
	type	name			(brief description)
	----	----			-------------------
	int	object_code		(always 6)
	int	upperleft_corner_x	(pixels)
	int	upperleft_corner_y	(pixels)
	int	lowerright_corner_x	(pixels)
	int	lowerright_corner_y	(pixels)

    Subsequent lines :
	objects
	.
	.

    Last line :
	-6

    (3.3) ELLIPSE

    First line :
	type	name			(brief description)
	----	----			-------------------
	int	object_code		(always 1)
	int	sub_type		(1 : ellipse defined by radiuses
					 2 : ellipse defined by diameters
					 3 : circle defined by radius
					 4 : circle defined by diameter)
	int	line_style		(enumeration type)
	int	thickness		(pixels)
	int	color			(not used)
	int	depth			(no units)
	int	pen			(not used)
	int	area_fill		(enumeration type)
	float	style_val		(pixels, not used)
	int	direction		(always 1)
	float	angle			(radian, the angle of the x-axis)
	int	center_x, center_y	(pixels)
	int	radius_x, radius_y	(pixels)
	int	start_x, start_y	(pixels; the 1st point entered)
	int	end_x, end_y		(pixels; the last point entered)

    (3.4) POLYLINE

    First line :
	type	name			(brief description)
	----	----			-------------------
	int	object_code		(always 2)
	int	sub_type		(1 : polyline
					 2 : box
					 3 : polygon
					 4 : arc-box)
	int	line_style		(enumeration type)
	int	thickness		(pixels, not used)
	int	color			(not used)
	int	depth			(not used)
	int	pen			(not used)
	int	area_fill		(enumeration type)
	float	style_val		(pixels)
	int	radius			(pixels)
	int	forward_arrow		(0: off, 1: on)
	int	backward_arrow		(0: off, 1: on)

    Forward arrow line : same as ARC object

    Backward arrow line : same as ARC object

    Points line :
	type	name			(brief description)
	----	----			-------------------
	int	x1, y1			(pixels)
	int	x2, y2			(pixels)
	  .
	  .
	int	xn, yn			(this will be the same as the 1st
					point for polygon and box)
	int	x, y			(always 9999, 9999; marks the end of
					point for polygon and box)

    (3.5) SPLINE

    First line :
	type	name			(brief description)
	----	----			-------------------
	int	object_code		(always 3)
	int	sub_type		(1 : open spline
					 2 : closed spline
					 3 : open interpolated spline
					 4 : closed interpolated spline)
	int	line_style		(See the end of this section)
	int	thickness		(pixels, not used)
	int	color			(not used)
	int	depth			(not used)
	int	pen			(not used)
	int	area_fill		(enumeration type)
	float	style_val		(pixels, not used)
	int	forward_arrow		(0: off, 1: on)
	int	backward_arrow		(0: off, 1: on)

    Forward arrow line : same as ARC object

    Backward arrow line : same as ARC object

    Points line : same as POLYLINE object

    Control points line (absent if sub_type is 1 or 2) :
	Control points of interpolated spline.  There are two control
	points for each knots.  A section i, of the spline is drawn
	using Bezier cubic with the following four points:
		(x ,y ), (rx ,ry ), (lx	  , ly   ), (x   , y   ).
		  i  i	    i	i      i+1    i+1     i+1   i+1
	For closed interpolated spline the last pair of control points,
	(lxn,lyn) and (rxn,ryn) (which can be ignored), are the same as
	(lx1,ly1) and (rx1,ry1) respectively.

	type	name			(brief description)
	----	----			-------------------
	float	lx1, ly1		(pixels)
	float	rx1, ry1		(pixels)
	float	lx2, ly2		(pixels)
	float	rx2, ry2		(pixels)
	  .
	  .
	float	lxn, lyn		(pixels)
	float	rxn, ryn		(pixels)

    (3.6) TEXT
	type	name			(brief description)
	----	----			-------------------
	int	object 			(always 4)
	int	sub_type		(0 : Left justified
					 1 : Center justified
					 2 : Right justified)
	int	font 			(enumeration type)
	int	font_size 		(points)
	int	pen			(not used)
	int	color			(not used)
	int	depth			(no units)
	int	angle			(radians)
	int	font_flags		(bit vector)
	int	height			(pixels)
	int	length			(pixels)
	int	x, y			(pixels, coordinate of the origin
					 of the string.  If sub_type = 0, it is
					 the lower left corner of the string.
					 If sub_type = 1, it is the lower
					 center.  Otherwise it is the lower
					 right corner of the string.)
	char	string[]		(ascii characters; starts after a blank
					character following the last number and
					ends before the character '\1'.  This
					character is not part of the string.
					Note that the string may contain '\n'.)