Whether the given type draws itself when sections says nothing about it.
sections
A panel of section controls needs this answer to show which switches start on. The map can't answer it. A type draws no layer for a route carrying none of its sections, so an absent layer reads the same as a type switched off.
const [drawn, optIn] = partition(drawnSectionTypes, sectionDrawsByDefault); Copy
const [drawn, optIn] = partition(drawnSectionTypes, sectionDrawsByDefault);
Whether the given type draws itself when
sectionssays nothing about it.