should we also briefly discuss the name of the function? In mathematical terms I would call it
support_region
But a more popularized name might be easier to understand in general. However, I do not like "touched" because "touch" is typically used in programming for denoting change in state, so your current name I understand it as a region that has state A and changes to state B. We could instead call it
intersected_target_region
or something similar. Other ideas?
In general I think we should spend some effort in good names because once a name is in the API it is more difficult to remove.
Best regards
Kostas