creation of self intersections

[ErichSzerencsits]

There are instructions how to remove self intersections, but nothing about their creation and avoidance. I run 'raster to polygon' using 'simplify polygons' in ArcGIS pro 2.63 and 'repair geometry' has to repair nearly all of the resulting polygons due to self intersections and this still doesn’t prevent ‘dissolve’ from crashing because of invalid topology. XY tolerance is set to 0.5 m and the raster resolution is 2 m. XY tolerance of 1 mm results the same. ESRI file.gdb is used.

What is ArcGIS doing and how to prevent self intersections?

[DanPatterson]

compare the simplify polygon version to the non-simplified version  You will see your answer.  You get unexpected outcomes around the edges of complex rasters with bits being "pinched" off. 

Which is why you should always run repair geometry on the result.

[ErichSzerencsits]

Thanks a lot! Well, this is a known but ignored problem?! No hint in the tool-reference of ArcGIS.

It would be great service, having a checkbox to choose if one wants the result of a function with or without geometry errors...

[DanPatterson]

That would apply to all tool use at some point in time. 

Now you know 😉

[ErichSzerencsits]

From: https://pro.arcgis.com/en/pro-app/tool-reference/data-management/checking-and-repairing-geometries.h...

"Unfortunately, some of these software packages—sometimes due to bugs, sometimes due to lack of knowledge—do not follow the documented specification."