You can use the Torus icon to measure the center diameter and ring diameter of the torus feature. The position of the barycenter of the points picked is also calculated.

To create a measured torus, you must take a minimum of seven hits. Take the first three hits on one level of the torus's center line circle (see the diagrams below). These hits must represent the orientation of the torus so that an imaginary circle generated through these three hits would have roughly the same vector as the torus.

Top-down view of a torus. Note the major diameter (1), the minor diameter (2), and the center line circle (3).

If you orient the torus and are looking down on it from a bird's eye view, with Z+ pointing up towards you, take the first three hits in a counter-clockwise direction to give the torus a vector of 0,0,1. If you take the hits in a clockwise direction, the torus will have a vector of (0,0,-1).

You can probe the remaining 4 hits in any random location as long as they all don't lie in the same plane.

Example Torus with 7 Points

Example Torus created from 7 points, with the first three taken in a counter clockwise direction

For information on the associated Edit window command, see the "Basic Measurement Format for a Torus" topic in the "Creating Measured Features" chapter.