Le 01/03/2017 à 16:43, Tomasz Wlostowski a écrit : > On 13.02.2017 18:04, Tomasz Wlostowski wrote: >> On 13.02.2017 17:26, Jon Evans wrote: >>> I verified using Novak's test case on the Launchpad bug report. DRC >>> error is generated if the distance between the tracks is exactly equal >>> to the clearance. >>> If you increase the spacing by the minimum distance recognized by the >>> software's precision, the DRC passes. >>> So, I think it's an issue of DRC specification -- The code currently >>> requires that the clearance be *larger* than the minimum in the design >>> rules. >>> The diff pair router is setting the spacing to the minimum (exactly) >>> which causes this bug. >>> >>> IMHO, the DRC code should be changed to "larger or equal to", but I am >>> not sure if there is some subtle reason why it is implemented this way. >>> If you tell KiCad that you can go down to 2mm clearance, you should be >>> able to design something with *exactly* 2mm clearance :-) >> >> Hi guys, >> >> The issue is a bit more complex: it's a mix of DRC's floating point >> inaccuracies as well as ill-defined (rounding-error-wise) fixed point >> calculations in the 'gateway' computation part of the diff pair code. >> I'll fix it when my time permits (certainly before v5.0). >> > > Hi again, > > I've fixed the rounding issues in the P&S code (patch attached), now the > diff pair gap should always equal the specified value. The DRC checker > still produces some errors, though. I've identified their source is the > DRC::checkMarginToCircle() function. The current clearance test > algorithm is quite complex for me to understand, so I couldn't see any > obvious rounding/comparison issues... > > @Jean-Pierre: could you have a look at the attached PCB file and the DRC > errors it produces? A trivial clearance check (see code below) finds no > clearance errors. > > Cheers, > Tom >
OK, I'll have a look at it. -- Jean-Pierre CHARRAS _______________________________________________ Mailing list: https://launchpad.net/~kicad-developers Post to : kicad-developers@lists.launchpad.net Unsubscribe : https://launchpad.net/~kicad-developers More help : https://help.launchpad.net/ListHelp
