Field_To_Polygon

Author

Jeff Wang, MCNC, Environmetal Programs Group 

Data

Input Data: Field 1-D 4-Space 1-Vector IRREGULAR Colormap (Optional)

Ouput Data: Geom

Network

An example network is shown below:

				read field
			 	   |
 	generate colormap ----- field to polygons
				   |
				geometry viewer
				   |
				geom reset 

Description

This module allows users to draw shaded polygons in the geometry viewer. The value of the polygo is mapped into color by the colormap of AVS. The input field is a 1D 4 space field with (x, y, z, n, value), where (x, y, z) is the coordinate of a vertex in the polygon, n is the number of vertices in the polygon, value is the value assign to the polygon. For example, a normalized unit square can be define as:

	(-1, -1, 0, 5, 1.0)
	(-1,  1, 0, 5, 1.0)
	( 1,  1, 0, 5, 1.0)
	( 1, -1, 0, 5, 1.0)
	(-1, -1, 0, 5, 1.0)

This is one of a suite of modules we used to plot the emission data for the state of North Carolina. This group of modules allows displaying points, lines and polygons over a map of the United States. The module suite is stored as a group in a compressed tar file at the International AVS Center, with some sample networks and datasets included. You may find it easier to access the modules this way. The compressed tar file is approximately 1.2MB in size, and can be found via anonymous ftp to avs.ncsc.org, in ftp/avs/Data/avs_dataWang_GIS_mods.tar.Z.