Posted by Holdstrong on Aug 14, 2024; 6:48pm
URL: https://forum.librecad.org/Properties-command-corrupts-coordinates-rounds-to-6-significant-figures-tp5725226.html

Have come across a potential problem which I have not been able to find a solution in the forums.
 
I have a large mapping file of around 6,000 KB with 130 layers which is referenced to an origin some 500,000 m away (500km).  The Properties command functions correctly on polyline elements but line elements are corrupted – I assume the coordinates are being rounded to 6 significant figures and written back (and stored) in their rounded format.

Short lines (2 – 3m long ?) disappear whereas longer lines (around 8 - 10 m) are reduced to 10m in length and changed to vertical or horizontal orientation.  I reckon the coordinates on longer lines also become rounded to 6 significant figures (10m accuracy where the work area is more than 100km from the origin ?).

Lines can be constructed with mm accuracy which appears to be retained unless the Properties function is applied to them.

Hopefully I havnt missed a parameter somewhere and this is an unintended consequence.  Hopefully an easy fix – so long as my prognosis (as a novice programmer and beginner Cad user) is correct !.

I am using Librecad Version 2.2.0.1 and the data file (hopefully) is attached.  Layer 0000 are boundary (long) lines and layer 0001 are a building (short detailed) lines.  Most (if not all) of the other layers are polylines.

The easy workaround is to move the origin but I will be trying to load some SHP files in the future which I assume have the same grid so would like to stick with the grid.  Also, I could put all new data as polylines, but again a bit of a faff (or not use Properties).
 
Hopefully, the above is helpful and apologies if I’ve cocked up.  Librecad is a brilliant tool.  Keep up the good work.