OffsetCurve -- TopologyException: found non-noded intersection between...

[jengland]

This is coming from shapely's parallel_offset. Here is an example:

from shapely import wkt, geos

print(geos.geos_version_string)

wkt.loads('LINESTRING (0 9, 21 30, 49 45, 61 70, 81 90)').parallel_offset(3)

Has the following output

3.8.0-CAPI-1.13.1 
TopologyException: found non-noded intersection between LINESTRING (50.4167 -21.6444, 22.8077 -36.435) and LINESTRING (22.8077 -36.435, 37.4683 -21.7743) at 22.807666014902189 -36.434974672217095
<python traceback>

I can mine them with the attached script at a rate of about 5-10 per 100,000 LineString s. The LineString s I'm trying are all simple (relatively straight on a 100x100 integer grid with 5 points each). And all the offsets are 0-9 ints.

This seems to be different from #682, because there the error message is different (i.e. TopologyException: assigned depths do not match at ...) and I cannot easily mine for exception of that message.

Hopefully it's acceptable to submit a .py example file. I can try to reproduce this using GEOS directly if necessary.

[jengland]

Python file using shapely to mine offset excpetions