This module is being donated from the Naval Research Lab/Research Computation
Division Visualization Lab.

Any questions, contact chas@ra.nrl.navy.mil

Thank you.

--chas iii
Local AVS Modules					   Vector Label(6)

NAME
     Vector Label - create labels/characters that are really geometries

SUMMARY
     Name	  Vector Label

     Type	  data	input

     Inputs	  none

     Outputs	  geometry

     Parameters	  Name		   Type		  Default	 Choices
                  Label           string	  ""
                  Kerning         float          1.0
                  Stroke Width    float          0.25
                  Font            choice         Roman Simplex  (many)
                  LineStyle       choice         Lines          Lines:Strokes:3D

DESCRIPTION

	This module produces labels that are geometries.  They can be scaled, 
	rotated, and translated.  Other geometric operators work as well, such
	as color, perspective, and material properties.

	The source for the vector information for the fonts is derived from the 
	Hershey Fonts, stored in comp.sources.unix, volume 4, on your nearest
	archive site.  The Hershey Fonts were originally created by Dr.  A. V.
	Hershey while working at the U.S. National Bureau of Standards.
	The format of the font data in the Internet distribution was
	originally created by

		James Hurt
		Cognition, Inc.
		900 Technology Park Drive
		Billerica, MA 01821
		(mit-eddie!ci-dandelion!hurt)


INPUTS

     none

PARAMETERS

     Label

	A string to convert into a geometry using the selected font.
        It is possible to mix fonts and get characters other than the
        keyboard ones.  Inserting \nnn will display the Hershey glyph
        corresponding to that number.  A useful list follows here:

	252       chemical bi-directional process
        274       copyright symbol
        731       phase/angle
        850-855   bullets (circle, square, triagles)
        857-874   map symbols (trees, flags, grass)
        899-907   circles of various sizes
        2077      aleph
        2078      angstrom
        2238-2244 equality operators (=,/=,=,<,>,=<,>=)
        2266-2270 del, sqrt, integral, line integral, infinity
        2279-2312 astronomical symbols
        2296-2299 various angled arrows
        2411      square root

        'Copyright \274 1992 by Your Lab Here' produces a copyright
        notice.  \n moves to a new line, i.e., 'Line 1\nLine 2'. \r
        moves to the beginning of line, for overstriking.  You can
        make a copyright symbol with, '\905\rC', although its not
        as nice as \274.

     Kerning

        Alters the spacing of the characters

     Stroke Width

        Alters the width used for the strokes in Stroke mode

     Font

	A list of fonts contained in the Hershey Fonts distribution.
        There are some other fonts (like Cyrillic) contained in the 
        distribution that could be implemented.

     LineStyle

	The Hershey fonts are a vector font and look best when rendered
        using Lines.  Stroke draws thick lines (i.e. flat polygons.)
        This can cause problems with line joins, however it should not
        be a problem with most stroke sizes.  3D is included as a demo.
        Its not quite done yet but looks neat.

OUTPUT
 
     geometry


EXAMPLE

		     VECTOR LABEL
			   |
		   GEOMETRY VIEWER

RELATED	MODULES

	geometry viewer

LIMITATIONS

	Mentioned above.  More information should be kept and used about
	the strokes relationships to each other.

SEE ALSO

	geometry viewer
        

Release	1			    		                Vector Label(6)