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 NAME: 
        Field to Isosurface : generate isosurfaces from 3D volume field

 SUMMARY:
        Name         Field to Isosurface

        Type         mapper

        Inputs       field 3D scalar byte uniform
                     colormap

        outputs      geometry

        Parameters   Name        Type   Default   Min   Max

                     Level       char   180       0     255

 
 DESCRIPTION:
        This module reads a uniform 3D volume data and passes a 
        threshold level to it to generate isosurfaces. 
        The algorithm is based on the Marching Cubes Method from
        Lorensen.
        Any interesting threshold level ranged from 0 to 255 can
        be input and the module will generate isosurfaces 
        corresponding to that level.
        After the generation of isosurfaces, you can see the 
        number counts of each table case on the console.

        Colormap is used for rendering the volume with one color
        level to a threshold. 

        The module is limited to the data type of char, but the 
        reader can change it into the other data type easily by
        modifying the source code a little.


 EXAMPLE: 

        Generate colormap       Read Field
                |                   |
                |                   |
                |                   | 
                |                   |
                ---------   ---------
                        |   |
                        |   |
                 Field to Isosurface
                          |
                          |
                   Geometry Viewer

 DATE:  
        May. 6, 1993
 
 AUTHOR:
        Chin-I Huang
        Computer Graphics Lab., Institute of Computer Science
        National Chiao Tung University
        SinChu, Taiwan 30043, Republic of China
        <email address> u8023552@cc.nctu.edu.tw
    
        hsv_to_rgb routine obtained from field2mesh
        written by:
           Wes Bethel
           Lawrence Berkeley Laboratory



CREDITS
-------

MODULE AUTHOR:	Chin-I Huang
                Computer Graphics Lab, Information and Computer Science,
		National Chao Tung University , Shin-Chu of Taiwan, ROC.
		email address: u8023552@cc.nctu.edu.tw

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