Computing Data Perpendicular To a Tilted Plane

This question came up today and it is a tough one - however with some testing you can solve it using the Curtting Plane View. The things you need to know about Cutting Plane View are

  1. Any object that you draw in the cutting plane will have a UCS (User Coordinate System)
  2. Define the plane using the TBC Plane Manager
  3. You can remove the UCS on an object drawn in Cutting Plane View using the Convert to Linestring command - this makes it a normal 3D object in TBC allowing you to draw to it / from it
  4. Objects drawn in Cutting Plane View while they have a UCS cannot be drawn to, joined to etc by objects in the normal Plan and 3D views that do not have a UCS - but remove the UCS and you can use them like any other object.
  5. If you draw a Polyline in the Cutting Plane View it is drawn on the cutting plane automatically.
  6. If you draw a linestring in the cutting plane view, because a linestring can have variable Z then it does not necessarily get drawn in the cutting plane unless it has UCS 0 elevation.
  7. If you use the Change Elevation Command on objects in the Cutting Plane View, it moves them perpendicular to the cutting plane (this is very handy)

Anyhow - now you know some of the secrets here - the video shows how to construct the perpendicular from a point in space to the plane and also from a point in the plane to an offset location to the plane but perpendicular to the plane.

1 Like