The planar surface has been substituted by the NURBS surface (see NURBS surface). The latter automatically detects if boundary lines lie in a plane and creates a planar NURBS.
Note: It is still possible, however, to access this function with the Right buttons menu (see Tools).
A planar surface is an entity formed by a closed set of lines, all of them lying on the same plane. These lines must share some common endpoints.
To create a planar surface, some lines must be selected (see Entity selection). The order of selection is not important but all of them must join each other by sharing common points and must form a closed contour. If all lines are not in the same plane the surface is not created.
It is possible to add holes to a planar surface. To do so, it is first necessary to create the outside planar surface. After this, press the Hole button and select the created surface. Then select lines that form every hole, one by one. Finish with escape. It is also possible to define the surface and holes at the same time, by selecting all the curves.
If the surfaces lie on the plane z=0, the orientation of the surfaces will be anti-clockwise in this plane (the normal vector points towards z positive). Otherwise, orientation will be arbitrary. This can be checked with the DrawNormals command (see Normals (only Preprocessing)).