> If you could tag a layer with attribs and one of those was color, > and allowed displaying with user-chosen colors, there would be no > loss of features, and increased clarity, (a layer purpose is outer, > inner, copper, conductive ink, insulator, etc.), one layer, one > layer number, one gerbr layer output.
The functionality we're losing is the ability to put, for example, ground on the ground plane on one layer, and signals on the ground plane on a different layer, so you can color code them separately. Example: http://www.delorie.com/pcb/m3a/board.pcb Two copper layers, but eight drawing layers. Separate colors for ground poly top, power poly top, ground poly bottom, power poly bottom, ground traces bottom, signal traces bottom, etc. > [jg]These first three don't fit DJ's proposed physical mapping of > layer purposes to physical board layers. In addition to physical order, there are tags (the "layer type" thing) for component, solder, inner, and "other", types. This lets you associate non-copper layers with copper layers. > > outline (& other mechanical notations) > [jg]goes on "ink layer"? No, it's its own layer. > > top silkscreen > [jg]goes on "ink layer"? It would be a silkscreen layer (one of 0..N) associated with the component side. > > bottom keepout layer > [jg] Doesn't fit DJ's proposed physical mapping Maybe I haven't explained the physical order thing. It's the copper layers we need to sequence properly, so we can match them up with the right copper layers elsewhere. Other layer types often have an implicit physical purpose, like "outline" and "drill". Still others are associated with some other physical side, like "top silk" (there's no "inner silk"). Still others are associated with specific layers, like keepouts, or with layer types, like inner-layer annulus limits. So there's a mix of "sequenced" and "unsequenced" layers. Hey, if it were easy, we'd have done it by now. All I'm suggesting so far is to use the layer order to sequence the copper layers, we'll have to figure out the rest as we go. _______________________________________________ geda-dev mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-dev
