topic Re: SketchViewModel – 2D snapping with automatic Z (like in ArcGIS Pro) in ArcGIS JavaScript Maps SDK Questions

SketchViewModel – 2D snapping with automatic Z (like in ArcGIS Pro)

KrzysztofNoga — Tue, 29 Jul 2025 13:52:06 GMT

When sketching with snapping on a 2D map, I'd like to achieve the same effect as in ArcGIS Pro. That is, the Z coordinate would be taken from the clicked vertex of another object, or if we click an edge, it would be calculated based on the vertices of the clicked edge.

Can this behavior be achieved using Sketch or SketchViewModel from the ArcGIS Maps SDK for JavaScript?

There is a video in the attachment showing the behavior in ArcGIS Pro.

Re: SketchViewModel – 2D snapping with automatic Z (like in ArcGIS Pro)

JonathanDawe_BAS — Wed, 30 Jul 2025 15:59:09 GMT

Unfortunately I don't think this is possible in the ArcGIS JS API. The client side geometry engine (and new geometry operators) mostly only work with 2D geometries. From past experience, the standard behaviour was that geometries in 2d maps didn't even bother bringing down the z coordinate in the requested geometries.

The issue is that this is a surprisingly non-trivial problem. A z-coordinate could represent an absolute height or a height relative to an underlying elevation surface. This means that it might not be as simple to interpolate a vertical height between the two points on an edge, you may need to also account for the underlying elevation model you are using.

Re: SketchViewModel – 2D snapping with automatic Z (like in ArcGIS Pro)

KrzysztofNoga — Tue, 05 Aug 2025 10:34:42 GMT

I agree... But if the coordinates are provided in "absolute height" mode, implementation shouldn't pose much difficulty.

Re: SketchViewModel – 2D snapping with automatic Z (like in ArcGIS Pro)

JonathanDawe_BAS — Tue, 05 Aug 2025 13:14:16 GMT

Agreed - it could assume absolute heights. Though as i understand it there is currently no way of storing in the data model what the z values represent. i.e. absolute vs relative heights....

Re: SketchViewModel – 2D snapping with automatic Z (like in ArcGIS Pro)

KrzysztofNoga — Tue, 19 Aug 2025 15:00:10 GMT

There is elevationInfo in FeatureLayer or GraphicsLayer

https://developers.arcgis.com/javascript/latest/api-reference/esri-layers-FeatureLayer.html#elevationInfo

Re: SketchViewModel – 2D snapping with automatic Z (like in ArcGIS Pro)

JonathanDawe_BAS — Thu, 11 Sep 2025 11:02:02 GMT

true, though this information is not stored at the service (Esri Rest) level meaning you would need to know that the z values are meant to be represented in a specific manner.

Re: SketchViewModel – 2D snapping with automatic Z (like in ArcGIS Pro)

KrzysztofNoga — Wed, 17 Sep 2025 12:49:18 GMT

Of course, this needs to be set at the stage of creating the FeatureLayer/GraphicsLayer object.

Re: SketchViewModel – 2D snapping with automatic Z (like in ArcGIS Pro)

mattheol — Fri, 26 Sep 2025 06:58:24 GMT

Bump
Is there any update on enabling Sketch/SketchViewModel in 2D MapView to carry/interpolate Z from the snapped feature (vertex → copy Z, edge → interpolate Z between endpoints) — assuming absolute heights? If unsupported, is there a recommended pattern or an enhancement on the roadmap?