NAME:       jigsaw

AUTHOR:     Ian Curington, Advanced Visual Systems, Inc.

TYPE:       Data Input

LANGUAGE:   C

INPUTS:     ASCII File, (jigsaw piece outline shapes)
            Field 1D Uniform Float (3-vector)
            Colormap

OUTPUTS:    Geometry

PARAMETERS: Filename,    Browser for shape file
            Scale        height scale factor
            Lock Pieces  toggle, transformation attributes

DESCRIPTION:

  Jigsaw creates a simple geometric object of extruded shapes, with
  input file control over contour of shapes. An AVS field
  controls the height, color, or visibility of each block.
  This module is similar to "Read Blokjes" at the IAC.
  Some degree of concave outline structure is allowed.
  Each piece has a unique name, and can be manipulated independenty
  in the geometry viewer, if lock mode is not selected.
  The color range is defined externally in the colormap data structure.
 
 Input ASCII file format for shapes:
 a list of jigsaw pieces, edge polyline lists:

Piece_1   Num_Points  Name_Tag_1
  X1,  Y1
  Xi,  Yi
  Xn,  Yn
Piece_2   Num_Points  Name_Tag_2
  X1,  Y1
  Xi,  Yi
  Xn,  Yn
 ...
 EOF
  
   The input field controls the height and color of each jigsaw piece.
   The field should be 1D, Uniform, floating point, with
   at least 3 values per element:
     Vector 0: visibility control (visible if >= zero)
     Vector 1: height             (z = height * scale dial )
     Vector 2: color              ( color of piece, using colormap )
  
   Only positive non-zero values of Vector-0 will be drawn.
   Negative cell values will hide the jigsaw piece
  
   Uses global object color, rather than vertex colors.
   The input colormap hi-low values control the color range,
   and is not automatically scaled.
  
   This module reads the file each time, even if it
   has not changed, only colors of field data.