This is a simple approach to draw a single outline around a selected object.
It is only working properly if the receiver plane don’t intersects with an other object.
Attachments
outlines2.64_node.blend (147 KB)
Great approach for this purpose! Though objects close to each other/ larger sized objects may introduce extra/less outlines.
Adding a ground plane wrecks it.
Maybe there is a way to make only certain objects have/cast shadows?
Otherwise, great idea 