Triangulate (TriangleFilter)
This filter converts polygons and triangle strips to basic triangles.
The Triangulate filter decomposes polygonal data into only triangles, points, and lines. It separates triangle strips and polylines into individual triangles and lines, respectively. The output is polygonal data. Some filters that take polygonal data as input require that the data be composed of triangles rather than other polygons, so passing your data through this filter first is useful in such situations. You should use this filter in these cases rather than the Tetrahedralize filter because they produce different output dataset types. The filters referenced require polygonal input, and the Tetrahedralize filter produces unstructured grid output.