Build a tiny box with BRepPrimAPI_MakeBox

Due to the default tolerance of 1e-7, we cannot build a tiny box whose size is smaller than the tolerance with BRepPrimAPI_MakeBox function. However, when I set the tolerance smaller, I cannot do it also. Please check if it is a bug or what I did is not right.

BRepBuilderAPI::Precision(1e-10);
BRepPrimAPI_MakeBox(1e-8, 1e-8, 1e-8);

Kirill Gavrilov's picture

Precision property in algorithms, when available, is intended to increase "default" precision, not to make it smaller. Some algorithms just unable to work with higher precision, so this does not make much sense to force creation of such small details - otherwise them will be broken somewhere else.

You have to use other units (e.g. millimeters instead of meters) if such precision is really required.