topic Re: Polygon symbol SceneView: no fill when points are directly on top of each other in ArcGIS JavaScript Maps SDK Questions

Polygon symbol SceneView: no fill when points are directly on top of each other

avecchi — Fri, 16 Dec 2022 16:31:16 GMT

Hello,
I am trying to render a vertical polygon (essentially a wall) in a SceneView and I am following this tutorial:
https://developers.arcgis.com/javascript/latest/sample-code/graphics-basic-3d/

For some reason, when the points are directly on top of each other, the fill of the polygon disappears but the outline remains. Here is the code that is rendering the polygon:

const polygon = { type: 'polygon', rings: [ [-104.95, 39.72, 5000], [-104.945, 39.725, 5000], [-104.945, 39.725, 8000], [-104.95, 39.72, 8000], [-104.95, 39.72, 5000] ] } const fillSymbol = { type: 'simple-fill', color: [227, 139, 79, 0.8], outline: { color: [255, 255, 255], width: 1 } } const polygonGraphic = new Graphic({ geometry: polygon, symbol: fillSymbol }) graphicsLayer.add(polygonGraphic)

Re: Polygon symbol SceneView: no fill when points are directly on top of each other

GreteSoosalu — Fri, 06 Jan 2023 14:19:37 GMT

Hi @avecchi, unfortunately, this is a current limitation and in our backlog.

Could you please explain a bit more the use case and how you would use such vertical polygons/walls? This can help us to prioritize since solving all possible cases is not trivial in 3D.

Re: Polygon symbol SceneView: no fill when points are directly on top of each other

avecchi — Fri, 06 Jan 2023 15:12:04 GMT

I'm displaying flight paths in 3D with lines and it's difficult to judge the altitude without something filling in the area below the line. Right now, I'm drawing vertical lines below every point on the flight path line to show the altitude but I feel like that is not a very performant way of handling this.

If you plot a line in a KML and open it in Google Earth, it will fill in the area below the line to show the altitude a little better. I was trying to do something similar. I have attached an image to give you a better idea of what I'm trying to do.

Re: Polygon symbol SceneView: no fill when points are directly on top of each other

GreteSoosalu — Fri, 06 Jan 2023 15:16:49 GMT

Thanks a lot, I'll note it down!

Re: Polygon symbol SceneView: no fill when points are directly on top of each other

GreteSoosalu — Fri, 20 Oct 2023 11:57:05 GMT

Hi @avecchi

We've installed a fix for the upcoming 4.28 release that goes out this October.
Let us know if you still run into any issues!

Re: Polygon symbol SceneView: no fill when points are directly on top of each other

avecchi — Thu, 25 Jul 2024 22:44:37 GMT

@GreteSoosalu Sorry for the late response.

It does appear to be fixed for a single "plane" shaped polygon. Thanks!

Unfortunately, when you start to add some more shape to it, the fill disappears once again.

I've included the rings that I used for the broken example. Could it be that I'm defining the rings incorrectly?

[ [ [-104, 39, 5000], [-104, 39, 10000], [-104.75, 39.5, 10000], [-105, 40, 10000], [-105, 40, 5000], [-104.75, 39.5, 5000], [-104, 39, 5000] ] ]

Re: Polygon symbol SceneView: no fill when points are directly on top of each other

GreteSoosalu — Thu, 19 Dec 2024 17:23:46 GMT

Hi @avecchi pardon for the extremely delayed response. Somehow I missed the notification of your post.

We looked into your example above and noticed that the polygon you're trying to draw is not fully planar.
A workaround is to split the polygon into several simpler ones. I know this is not ideal but, unfortunately, this is a technical limitation we currently have in 3D.