Here is a SketchUp file containing 2 faces in the model and one face in a group.
Intersect_with impossible.skp (25.6 KB)
If you use the intersect_with method (Class: Sketchup::Entities — SketchUp Ruby API Documentation) to get the intersection between the group and the model, there is no intersection for the face in blue. Here is a code to use the method on the provided file:
m = Sketchup.active_model # group containing a face that is a cutting plane of model entities section_group = m.find_entity_by_persistent_id(2719083) # intersecting the model entities and the section group (the intersection entities are drawn in the section group) m.entities.intersect_with(false, Geom::Transformation.new, section_group, section_group.transformation, false, section_group)
No matter how hard I look, I don’t see why this face refuses to be intersected. Do you have any explanation?