PNS router: sometimes routing start falsely denied with warnmessage "routing start violates DRC"

Description

With coarse grid-settings sometimes the routing start is denied with the yellow warn-message (at top of screen) "The routing start point vialates DRC".

circumstances:

  • in every router mode
  • only noticable with coarse grid settings
  • only relevant if one tries to start a track on an already existing track
  • the mouse-pointer has to be a little away from the track, but not so much as to start at next grid-point
  • if the mouse-pointer is moved directly over the track the routing-start works well, so no show-stopper, only irritating

guesswork:

  • the online-drc seems to take the real cursor-position (instead of the route-cross-cursor which is snapped to the grid/track) into account?
  • the online-drc has not realised that the new track should get the same net-name as the already existing track?

Steps to reproduce

  1. open attached project
  2. set grid to 1mm
  3. zoom to full view
  4. try to create a track extending from the thin track:
  5. hover mouse-pointer at the center of the circle
  6. "X" as hotkey "start route tracks", observe:
  7. the routing-cross is displayed at (31,16), so the routing-engine accepts a valide starting point
  8. but at the same time the warn-message at the top is displayed and refuses the routing

warn_0102

test8_unable_routing_start.zip

KiCad Version

Application: KiCad PCB Editor (64-bit)

Version: (6.0.0-rc1-48-g8f87638de5), release build

Libraries:
	wxWidgets 3.1.5

Platform: Windows 10 (build 19042), 64-bit edition, 64 bit, Little endian, wxMSW

	wxWidgets: 3.1.5 (wchar_t,wx containers)
	Boost: 1.76.0
	OCC: 7.5.0
	Curl: 7.78.0-DEV
	ngspice: 35
	Compiler: Visual C++ 1929 without C++ ABI

Build settings:
	KICAD_USE_OCC=ON
	KICAD_SPICE=ON