About makeBoxProperties() function

Hi everyone!
Could anybody explain to me what does argument _frags in function makeBoxProperties() of dart::dynamics::SoftBodyNodeHelper class mean please?
Documentation says: “Specify the number of vertices along each axis with _frags.” But what are those vertices and how do they affect simulation of the soft of body?
There is also another function with the same name but without _frags argument described as followed: “Create a Properties struct for a box-shaped with 8 PointMasses”.
Does _frags has anything to do with point masses?
Any feedback would be appreciated, thanks in advance!

Yes, I believe _frags determines the number of point masses. The version of makeBoxProperties() that does not accept a _frags argument is a special case where there will only be a point mass at each corner of the box.

In general the soft bodies expect at least 3 point masses along each edge of the box (one at each corner and one in the middle of the edge). I’m not sure if there was a specific motivation for that restriction, but that’s how the API was designed.

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Thank you very much for your answer! :100:
Do you know if point masses will be evenly distributed across cube faces if I choose larger value for _frags?

Yes, they should all be spaced out with equal distances between each other along the edges.

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Thank you very much again!