Bug #2034: Measurement arrowheads are ridiculously out of proportion at some scales/zooms/measurements.

[Kunda1]

issue #2034: Measurement arrowheads are ridiculously out of proportion at some scales/zooms/measurements

Description
See http://www.toms.net/FreeCAD/fc2.png

Steps To Reproduce
measure something small

Additional Information
arrowheads even overlap into hourglasses

[Kunda1]

@NormandC could reproduce:

I confirm this bug in current master.

Steps to reproduce:

1. Create a Part Cube of dimensions 0.1 x 0.1 x 0.1 mm
2. Select two vertices
3. Click on "Measure Linear" from the Measure toolbar in the Part workbench
4. The measurement arrows are disproportionally huge.

OS: Ubuntu 14.04.5 LTS
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.9747 (Git)
Build type: None
Branch: master
Hash: f5c0f579cbd7ce668727f8835946e4e9abc0eec6
Python version: 2.7.6
Qt version: 4.8.6
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17