The data imported into polyTRIM as .dxf files from autoCAD consisted of contours that had been raised to their altitudes, with all other features 2-D outlines at zero altitude. The ground plane was constructed by automatically triangulating the points on the contours.
Creation of the roads was the most laborious part of the process. The road system was partitioned into several dxf files, so that fewer incorrect triangles would be generated between parallel, close roads. When each file was brought in and triangulated (still in 2-D), extra triangles that were generated had to be deleted: triangulation connects every point in the layer. This editing was facilitated by the various picking features of polyTRIM, especially cross pick.
For more information, please e-mail Dan Ancona at email@example.com.
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