On Mon, Sep 06, 2010 at 10:43:50AM -0600, John Doty wrote: > > On Sep 6, 2010, at 10:33 AM, Andrew Poelstra wrote: > > > On Mon, Sep 06, 2010 at 09:53:36AM -0600, John Doty wrote: > >> > >> Need some geometric shapes. Need to be able to attach material properties > >> to them (including "vacuum" for holes). > >> > > > > How about?: > > trace (inc. arcs, pads) > > Trace? Pad? Forget them: they aren't primitive geometric concepts. Remember, > all shapes should support any use by any material, or vacuum, in any layer > or collection of layers. A "trace" is a particular (usually itself composite) > shape of conductive material. >
I don't think we want to drop all the way down to geometric shapes - at some point, why not just call numbers and strings primitives and forget this whole discussion? A trace has a length, width, and curvature, which are different properties than that of a polygon (which is a set of points, so I suppose isn't really a primitive), or a circle, which has a radius and sweep angle. Perhaps "line" is the word I should be using. > > polygon (inc. rectangle, etc) > > What's the distinction here? > No distinction. I'm just indicating the scope of these primitives. > > circle (inc. quarter-circle, half-circle) > > Versus arc? > A circle could be considered as a "filled arc". I have been considering arcs as "curved lines", which I think makes more sense. > > via > > Definitely not primitive. A hole in one or more layers with conductive > material in it. > Again, while geometrically a via is not primitive, I think that in PCB terms, a via is primitive. It can exist on several layers, which the other shapes do not, so it doesn't make sense to build it out of other shapes. Andrew _______________________________________________ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user