Enabling correct unbound use of LevelSet::distance for in-grid points
Before:
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In [1]: b = levelSetBody("sphere",radius=1)
In [2]: b.shape.distance(Vector3.Zero,True)
Out[2]: 0.0 # Wrong, the origin is not part of the sphere
After:
In [1]: b = levelSetBody("sphere",radius=1)
In [2]: b.shape.distance(Vector3.Zero,True)
Out[2]: -1.0 # Correct