[[EM.Terrano]] allows you to draw any type of surface or solid CAD objects under impenetrable and penetrable surface groups or penetrable volumes. Some of these objects have flat faces such as boxes, pyramids, etc. Some others contain curved surfaces or curved boundaries such as cylinders, cones, etc. All the non-flat surfaces have to be discretized in the form of a collection of smaller flat facets. [[EM.Terrano]] uses a triangular surface mesh generator to discretize the non-flat surface. Unlike [[EM.Cube]]'s other computational modules, EM.Terrano's surface mesh does not depend on the operating wavelength. Its sole purpose is to discretize curved scatterers into a flat facets. Therefore, geometrical fidelity is the only criterion for the quality of a SBR mesh.
{{Note|Discretizing smooth objects using a triangular surface mesh gives rise to a large number of small edges among the facets that are simply mesh artifacts and should not be considered as diffracting edges.}}.
=== Viewing & Modifying the SBR Mesh ===