[LUCENE-8556] Tessellator: Polygons can fail when using Morton optimisation

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 7.6, 8.0
• Fix Version/s: 7.6, 8.0
• Component/s: modules/sandbox
• Lucene Fields: New
• Assignee: Ignacio Vera
• Reporter: Ignacio Vera
• Created: 02/Nov/18 07:51
• Updated: 14/Mar/19 13:07
• Resolved: 09/Nov/18 06:25

Description

I experience some errors when processing complex polygons. I realised that if I disable the Morton optimisation, then the errors go away.

I studied one of the cases and it seems that when using the optimisation, it is possible to create triangles with points inside of them (see picture attached). There is a point just on the edge of the triangle. When disabling the optimisation, such a triangle is not created.