If we really want this we might look into fully supporting arbitrary rotations as a first step. the current method is a elegant hack\b\b\b\b workaround.
adding a rotation field to the data structures would be what is required for DRC checking ( i believe that it still assumes 90 degree rotations ) pick and place exports other stuff.....??? Hardkrash On Mon, Feb 25, 2008 at 5:22 PM, Dan McMahill <[EMAIL PROTECTED]> wrote: > Dave N6NZ wrote: > > > OK, I'll take a look at doing some testing. I can think of three > > footprints where I have the same pin number. One is a SPST momentary > > switch with four legs, and the other two have big heat sink pads with > > the same pin numbers as ground. > > I think the multiple pin thing will just weigh in more and shift the > computed centroid towards the multiple pins. > > > >> I'm not sure how to make the algorithm properly deal with angles other > >> than multiples of 90 degrees. That is a pretty major assumption. > > > > What are the barriers to other angles? > > Think about a SOIC package for example. It is fairly easy to decide > what quadrant pin #1 is and once you know that, you're done if you only > allow 90 degree steps. Now suppose you allow 45 degree steps. Pin 1 > for a SO6 will be in a different 45 degree slice than pin 1 of a SO16 of > the same orientation. If you want to support arbitrary rotations, you > now have to take more steps to estimate what the axis of the part is. > There could be some metrics like "look for rows of pins that fall on a > line" but that will clearly fail for something that has its pads/pins > distributed around a circle. > > I'm not saying it can't be done, I'm just saying it gets more > complicated and you probably need a lot of heuristics to deside what > constitutes zero degrees for the part. > > This is the advantage of storing the center and rotation of each > footprint in the library. You can deal with arbitrary footprints with > arbitrary rotations. The downside is you now have an opportunity for > human error on every single footprint. > > Still, the suggestion about letting a footprint optionally include this > information to deal with "problem" parts might be an option. > > -Dan > > > > > _______________________________________________ > geda-user mailing list > [email protected] > http://www.seul.org/cgi-bin/mailman/listinfo/geda-user > _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
