QCAD Bugtracker

  • Status Assigned
  • Percent Complete
  • Task Type Bug Report
  • Category QCAD (main)
  • Assigned To
  • Operating System All
  • Severity Low
  • Priority Very Low
  • Reported Version 3.25.2
  • Due in Version Undecided
  • Due Date Undecided
  • Votes 1
    • CVH (23.12.2020)
  • Private
Attached to Project: QCAD Bugtracker
Opened by CVH - 22.12.2020
Last edited by CVH - 23.12.2020

FS#2157 - Controlpoint Spline exploded to polyline may induce NaNs Widths

QCAD Professional
Win installer 32bit
Version: (
Internet: QCAD.org
Build Date: Dec 16 2020
Revision: e06f230
Qt Version: 5.13.2
Architecture: i386
Compiler: Unknown

Documented in, reproducible under
In the attached file:
→ Explode the trial cases and locate NaN Widths.
→ These faulty widths are cleared while saving and reverting.
= work around.

Related Post: https://www.qcad.org/rsforum/viewtopic.php?t=7902#p30902
Related Topic: https://www.qcad.org/rsforum/viewtopic.php?t=7901
Related Commit: https://github.com/qcad/qcad/commit/fcd7929bced7ae328029c1aa2ee2aff2745709c6

Arctic_Eddie reports failing CAM offset at exactly these points !!!
Reported is a faulty arc with radius of over 360,000mm.
- I can not reproduce this under QCAD working further on the Polys with NaNs.
- However the direct offset of such controlpoint Splines is erroneous.
(see file in post 30902)

Arctic_Eddie reports arc radii of over 10,000mm.
- These don’t seem to be faulty.
- I agree that BiArc fitting should be bound to a lower and certainly to an upper limit.
- That should be huge otherwise faint curvature is represented by many
wobbles or too quick by straight lines.
(All this, keeping in mind that QCAD doesn’t return the optimum fitted BiArc, see: https://www.qcad.org/rsforum/viewtopic.php?t=4859)


CVH commented on 22.12.2020 06:24

Again: wrongtoken, not able to go back.
Had the text preserved in Notepad.


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