Autorouter places via too close to track

[LaunchpadLoginDefectReport]

Freeroute and DRC don't quite agree on clearances. Freeroute placed a via too close to a track for DRC to be happy with it. There's plenty of room to place the via; this isn't a hard case.

Picture attached. Files on Github at
https://github.com/John-Nagle/ttyloopdriver

It's really close to being correct. It looks like DRC wants slightly more clearance than Freeroute does. This might even be a rounding error.

Application: kicad
Version: 4.0.6-e0-6349~53~ubuntu14.04.1 release build
wxWidgets: Version 3.0.2 (debug,wchar_t,compiler with C++ ABI 1002,GCC 4.8.4,wx containers,compatible with 2.8)
Platform: Linux 3.13.0-113-generic x86_64, 64 bit, Little endian, wxGTK
Boost version: 1.54.0
Curl version: libcurl/7.35.0 OpenSSL/1.0.1f zlib/1.2.8 libidn/1.28 librtmp/2.3
         USE_WX_GRAPHICS_CONTEXT=OFF
         USE_WX_OVERLAY=OFF
         KICAD_SCRIPTING=ON
         KICAD_SCRIPTING_MODULES=ON
         KICAD_SCRIPTING_WXPYTHON=ON
         USE_FP_LIB_TABLE=HARD_CODED_ON
         BUILD_GITHUB_PLUGIN=ON

[Eldar Khayrullin (eldar)]

Is it the duplicate of https://bugs.launchpad.net/kicad/+bug/1593373 ?

[LaunchpadLoginDefectReport (nagle-1)]

It may be a duplicate of that DRC bug. Not sure whether the autorouter cut it too close or
DRC generated a false alarm. Check my math here, please. See previously attached picture
for situation and numbers below.

Track near via error message:
(111.580mm, 112.014mm): Track 1.000 mm (a vertical track)
(110.335mm, 113.229mm): Via 0.600 mm

Track width 1 mm. Track clearance 0.5 mm. Via diameter 0.600 mm

111.580mm - 110.335mm = 1.2450 mm between center of track and center of via.
1.2450mm - (1.0/2mm) - (0.600/2mm) = 0.4450 mm clearance between track and via.
0.5mm clearance allowed - 0.4450mm clearance actual = 0.0550 mm too close.

That says DRC is right, there really is an overlap. The autorouter is wrong. Is that correct?
Again, please check me on this.

(Making a trivial change to the board elsewhere and re-running the autorouter resulted in a
different layout that passed DRC.)

[Jeff Young (jeyjey)]

FreeRoute is no longer supported by its developer (as I understand) and we're putting our effort into the Push-n-Shove router.

(Of course if you were using the integrated PNS router and just mistakenly called it the old name, then please re-open.)