AVS Modules							Extrude
University of Texas- Center For High Performance Computing      19th August, 1992

NAME
	Extrude

SUMMARY
	Name	Extrude
	Type	data
	Inputs	Not required
	Output	geom
	Parameters	Name		Type		Default
    			Filename	string		NULL
    			Depth           float		5.0

DESCRIPTION

	This module reads an ASCII file consisting of lists of
	x & y points and constructs a 3-D geometry object using
	the points in the file as vertices.  It uses the value
        specified by the user in the depth dial for the depth 
	of the object.

	The file format this module expects is as follows:

	num_vertices		(integer)
	x y                 (floating point values)
	x y
	  .
	  .
	x y 
	<eof>

INPUTS
     	No input is required

PARAMETERS

	Filename
		A file browser is supplied allowing the user to specify
		a filename for extrude to read.

	Depth
		It is a dial which is to be used to change the depth or
                thickness of the 3-D object. 

OUTPUTS

     A GEOMedit_list which contains a 3-d geometry object, of user supplied
     depth, generated by connecting the vertices specified by the user.


EXAMPLE

      Extrusion
	    |
      RENDER GEOMETRY
            |
      DISPLAY PIXMAP

LIMITATIONS
           If the number of vertices exceed a certain limit then
           one would see streaks emitting from vertices and in
           order to get rid of this problem, you will have to
           turn on the software renderer(geometry viewer-cameras
           -software renderer). This problem is apparently due
           to a bug in GEOM_CONCAVE.

AVS Modules							Extrude
University of Texas-Center For High Performance Computing         19th August, 1992