Line MAT inside bias

Not sure if this is an RFE / Wishlist, or there’s a way to make it happen that’s escaping me, but I would love it if the Line MAT could be offset to draw from the outside or inside edge of the geometry and not grow from the center. My usecase is an LED wall outliner application; I want to be able to add edges to a polygon that don’t extend past the limits of their associated quad, so that line width only grows borders on the inside and they won’t bleed into adjascent led segments, particularly problematic when they are butted up against each other.

While I’m on the topic, it would also be great if there were a Line Joint Type that accurately created hard edges on 90 degree corners; Neither round, bevel or miter really do what I want when outlining a basic grid for example.