This PR restructures layers (yet again), so they have pixels per unit values and work on some arbitrary units (the same units already being used by the objects). This allows us to collate layers at different positions and should allow us to more easily scale layers later.
This PR restructures layers (yet again), so they have pixels per unit values and work on some arbitrary units (the same units already being used by the objects). This allows us to collate layers at different positions and should allow us to more easily scale layers later.