[Chimera-users] Calculating and showing the Mass center of Volume Segments

Hello, I got a volume map that I segmented in 4 parts. Now I wanted to measure how the parts are coordinated to each other. As the Axes/Planes/Centroids menu can only create planes by atoms I wanted to place atoms in the mass- center of each segment. Is there any way to realize that? Or do you have any other way to measure the angles. To explain what I'm trying to measure: Example you have 4 segments, I call them a b c d. I want to measure how the axis that is formed by a and b, forms an angle to c and d, or how ist he angle of the plane formed by a b and c compared to ab and d . All for segments are basically the same objects just turned and rotated. With best regards C. Schmidt