+ Note:
+ The actual grid spacing can slightly differ from the defined one. This is done for the
+ best fitting of polyhedrons and for a better mesh quality on the interval boundaries.
+ For example, if a constant **Spacing** is defined along an axis, the actual grid will
+ fill the shape's dimension L along this axis with round number of equal cells:
+ Spacing_actual = L / round( L / Spacing_defined ).