Geometry Validator not repairing Self Intersection

Can you share that geometry? When I recreate one it does fail the geometry validation
 

What are you wanting to do with it? Are you wanting it to be split into two seperate geometries? If so a tiny negative buffer, then deaggreate then anchored snapper (surround parcels are the anchors) should help achieve that

Hi ​@joshuajames1979 ,

According to your explanation, I assume that the input geometry is so called "pinch" shape - a polygon with a single boundary having hole-like part formed by two vertices touching each other, like this screenshot. Numbers represent the order of vertices on the polygon boundary, vertex #4 and vertex #8 touch each other.

However, I think GeometryValidater (Issue to Detect : Self-Intersections in 2D) should detect such a "pinch" shape as an invalid geometry and repair it to a donut - consisting of an exterior boundary (outershell) and an interior boundary (hole), by default. The outershell and the hole will touch at a point, but it's an OGC complient valid geometry.

Could you please explain some more detail about your situation including input geometry shape, GeometyValidator parameters setting, preferable repaired shape, etc.?

Hi Takashi. I think that’s correct. I’ve attached the polygon. Currently I’m altering every polygon slightly with tiny buffers but if this section could be made valid without affecting other geometries that would be great. Even if FME added a vertex to shift the touching vertex a tiny bit so remove the self intersection.

Even if it did something like this just for this polygon, but at a minute scale.

Currently I have a tiny buffer of .0000001 and then I dissolve then aggregate and then do a validate to remove any introduced geometry errors, only because the above situation seemed to be detected but not repaired.

Thank you for sharing the sample.

The geometry sample you shared is not a "pinch" shape, is a donut (polygon with holes) geometry self-touching.

Generally you can consider self-touching donut as a valid geometry, and it will be output via Passed port of GeometryValidater if you set "No" (default) to the Check Self-Touching Polygon parameter.

Do you have any inconvenient if there are self-touching donuts in the dataset?

Thanks for the reply. The process that imports this dataset in our property and rating system is treating it as invalid so the process fails. We also had a geometry error in our CRM if that property was selected. Perhaps I can use another transformer to detect touching vertices that remain after geometry validation and where they touch shift one vertex by a very small amount.

Thanks very much for that. I’ve taken your example and tweaked it to get it working. I was able to go from buffer of invalid locations straight to dissolve and aggregate them back, but I think this works nicely so thanks.