topic Re: Arcade negative Buffer returns null in ArcGIS Pro Questions

Arcade negative Buffer returns null

Jan62 — Tue, 26 Nov 2024 07:09:40 GMT

I am trying to create a negative Buffer in Arcade to query features inside, as it was possible in older versions (2022). When I execute it noch for example in the Arcade Playground "null" is returned instead of a shrink polygon.

To reproduce open the Arcade Playground https://developers.arcgis.com/arcade/playground/ and insert

var poly = Polygon( { rings: [ [ Point( { x: -97.06138, y: 32.837, z: 100, hasZ: true, spatialReference: { wkid: 3857 } } ), Point( { x: -97.06133, y: 32.836, z: 50, hasZ: true, spatialReference: { wkid: 3857 } } ), Point( { x: -97.06124, y: 32.834, z: 20, hasZ: true, spatialReference: { wkid: 3857 } } ), Point( { x: -97.06127, y: 32.832, z: 0, hasZ: true, spatialReference: { wkid: 3857 } } ) ] ], hasZ: true, spatialReference: { wkid: 3857 } } ); Buffer(poly, -10) //return null //BufferGeodetic(poly, -10) //return null

Is this a bug or intention?

Re: Arcade negative Buffer returns null

DanPatterson — Tue, 26 Nov 2024 10:43:25 GMT

not sure about arcade but most polygon geometry usually has a duplicate first and last point, what you have given could be interpreted as a polyline

Re: Arcade negative Buffer returns null

Jan62 — Tue, 26 Nov 2024 11:16:35 GMT

Yes but it's the example polygon of the Arcade Playground. The result is also null if i add the first point at the end.

Re: Arcade negative Buffer returns null

DanPatterson — Tue, 26 Nov 2024 13:53:12 GMT

then the buffer size is too large relative to the size of the polygon (eg. bigger than its extent)

Re: Arcade negative Buffer returns null

Jan62 — Mon, 02 Dec 2024 08:01:14 GMT

Yeah you are right the polygon was to small. (why is the default playground polygon so small?). This was also the error for the "Attribute Rule" I wanted to save. If the buffer is -1 (meters), the verification of the arcade statement fails. Under -0.3 the expression is valid.

Wich polygon is used for the statement verification in attribute rules in Pro 3.3?

Re: Arcade negative Buffer returns null

DanPatterson — Mon, 02 Dec 2024 10:10:06 GMT

It would be prudent to calculate the poly extent in planar coordinates prior to trying a negative buffer. At least the extent would give you the ability to assess other values like perimeter, area and other possible measures.