This week we discuss a command that was introduced in GeoTools a couple of months back - GT_TRIANGULATE. This command in GeoTools is used to create Delauney triangles (TIN model). Using Delauney triangles, you can connect a network of irregularly spaced points with lines forming the smallest possible, non-intersecting triangles covering the entire expanse of points. Located under the GeoTools->Civil Tools menu, this has been the newest addition to the Civil Tools collection.
The TIN algorithm is Lisp-based and not the fastest but it nevertheless does its job, if you are patient and give it some time.
Upon starting the GT_TRIANGULATE command, you will see a dialog box which offers a simple choice that looks like this (below):
You can choose to have your TIN mesh represented by 3dface objects or 3d polyline objects. Actually, the choice of 3dface or 3d polyline objects is provided mainly for convenience here. You can anyway convert a 3dpolyline to 3dface and vice-versa using other tools in GeoTools, namely GT_3DF2PL and GT_PL23DFACE. Once you click Ok, the triangles are computed and drawn. The end result will look something like this:
Now, creating this mesh of triangles is just the beginning. You can do a lot more interesting stuff with this mesh and with other GeoTools commands. And there is a very interesting performance issue when this command is used in GeoTools for AutoCAD and in GeoTools for Bricscad. All of this and MORE in another post. Stay tuned...
If you wish to use the same test data that we used in this illustration, click here (TIN_Points.DWG).
You can read this blog in Spanish also. Click here...