If there are no options settets and settets/color_tets sets the color of all elements using the following tests. If the element contains a non-interface point, the element color is set to this value. If the element is comprised entirely of interface points, the centroid of the element is calculated and the material region containing this point is determined; the element color is set to this material. If the centroid of the element is not in any material region, the centroid must be on an interface surface. In this case all vertices of the element are examined and the material common to all vertices is selected as the element color.

settets/ parents has exactly the same behavior as settets except that existing values of itetclr are used for elements containing non-interface nodes.

geometry  sets the  element color  based on the material region containing the centroid of the element for all elements; existing values of itetclr are ignored.

color_points  sets the node material (imt1) from the element color (itetclr); existing values of itetclr are not changed.

settets/newtets has the same behavior as settets except that existing positive values of itetclr are not changed.

settets/normal assigns the itetclr array of a triangle mesh to an integer value depending on the normal vector direction.  There are 26 possible direction that correspond to the 6 faces, 12 edges and 8 corners of a cube.  In general most triangles will be assigned one of 6 values which correspond to the 6 sectors which are within 45 degrees of the 6 unit vectors: 1 0 0 , 0 1 0 , 0 0 1, -1 0 0, 0 -1 0, 0 0 -1
NOTE:  Valid only for triangle mesh.