> Moving forward, it would be best if PCB didn't hardcode the concept of > layer type into specific layers. Rather, you should just define > whether the layer is silk, mask, or metal, and additionally define > whether it is positive or negative.
That is a very BAD idea. PCB is not a drawing tool; it understands things like design rules, connectivity etc. It makes no sense to have software to trace connectivity on the silk, mask, keepout, etc layers or to not be able to understand that metal layer DRCs are different from the silk layer, or to deal with elements having various "grouped" metal, mask, and silk features if all layers were arbitrary. h.
