PATCH: Node3D: apply round(value, 10) to node coordinates when testing equality

[mglover]

My code was iterating through a mesh, defining supports. This was no problem until I added a y_control to the mesh, at which point some of the supports disappeared.

I looked through the examples and noticed they all use round(value, 10) in this case, and I added that to my code and it solved the problem. This seems like just a floating point precision problem. Correct?

It also seems like moving the call to round() into the library would be an improvement.

I wrote a patch to Node3D.py (attached) that:

• adds class RoundFloat(float) that overrides the equality operator to compare the rounded values
• added getters and setters for X, Y, and Z that store RoundFloat objects instead of floats

The patch should only affect comparisons between node coordinates and floats. It is working for me and doesn't seem to have a measurable performance impact. Thoughts appreciated.