When dealing with polygon features in Oracle Spatial, the feature definition provides an option to toggle support for non-planer shapes. This option is available for both polygons and polygon collections and determines the contents of the Plane Constraint drop down list.
For a registered feature class, the value of this toggle would be stored in the feature’s registration information in the ECRelationalDbMapping class property allowNonPlanar. See last paragraph for discussion of this property’s usage during Oracle geometry validation.
When Support non-planar shapes is toggled ON, the drop-down list contents are:
Area of the projected polygon to the ground
Area of the projected polygon to the average plane
Area of the mesh
If Support non-planar shapes is toggled OFF, the drop down list contents are:
Area of the polygon
For a polygon collection feature definition, if Support non-planar shapes is toggled ON, the drop down list contents are:
Area of the projected polygon collection to the ground
Total of the areas of the projected polygon to the average plane per polygon
Total of the areas of the meshes
Total area of all polygons
For a registered feature class, the value of this drop-down list would be used to determine the value of the isHorizontal property in the ECRelationalDbMapping class of the feature’s registration information. The allowNonPlanar and isHorizontal property values are used during posting to Oracle when validating geometry.
When allowNonPlanar is True/ON, and isHorizontal is set as:
When allowNonPlanar is False/OFF, then geometry validation is performed normally, meaning with whatever validation their database supports by default (e.g. 11g, 12c).