2D and 3D distance dimensions in the Distance dialog box (Insert | Dimension | Distance) apply the following rules according to the related features:
Treatment of Features
Spheres, Points, Circles, and Sets are treated as Points.
Slots, Cylinders, Cones, Lines, and 2D Widths are treated as Lines.
Planes and 3D Widths are treated as Planes.
Other Rules
If both elements are points (as defined above), PC-DMIS gives the shortest distance from point to point.
If one element is a line (as defined above) and the other is a point, PC-DMIS gives the shortest distance between the line (or centerline) and the point.
If both elements are lines, and the Shortest check box is not selected, PC-DMIS gives the shortest distance between the centroid of the first line to the second line. See the "Shortest check box" topic for what happens when it is selected.
If one element is a plane and the other is a line, PC-DMIS gives the shortest distance between the centroid of the line and the plane
If one element is a plane and the other is a point, PC-DMIS gives the shortest distance between the point and the plane.
If both elements are planes, PC-DMIS gives the shortest distance between the centroid of the first plane to the second plane.
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