Cylinder Entity not rendering at correct height or clamping to ground about cesium

[ggetz]

What we want is for the cylinder to be clamped to the terrain almost "painting" the mountain and to be 1000 meters above the center point.

Can you expand on this a little?

Expected behavior of CLAMP_TO_GROUND is shown in this example.

If instead you're looking for terrain classification, see this example

[parker-the-king]

Ok, so we want our cylinders to behave exactly as the squares in the CLAMP_TO_GROUND example that you sent me. Instead of stopping when they hit the ground, they extend all the way into the ground and we can see the part that's underground which looks weird. We want the top of the cylinder to extend 1000 m above the center point of the cylinder (which is touching the ground) and we want them to extend all the way down to the ground, but not through it.

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On Thu, Apr 4, 2024 at 8:03 AM Gabby Getz ***@***.***> wrote: What we want is for the cylinder to be clamped to the terrain almost "painting" the mountain and to be 1000 meters above the center point. Can you expand on this a little? Expected behavior of CLAMP_TO_GROUND is shown in this example <https://sandcastle.cesium.com/?src=Geometry%20Height%20Reference.html>. If instead you're looking for terrain classification, see this example <https://sandcastle.cesium.com/?src=Classification.html.> — Reply to this email directly, view it on GitHub <#11921 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AK2UXVQBOF7AZBXPNLRSWX3Y3VMS5AVCNFSM6AAAAABFWDW3C6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDAMZXGMYDKNBXGY> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[ggetz]

Gotcha @parker-the-king. Is it possible to use RELATIVE_TO_GROUND and offset the height by the half the height of the cylinder (500m in this case)?

[parker-the-king]

We tried what you said in the sandbox and it worked perfectly.(Pictured in the second picture below) Then we copied the exact same code into our application and for some reason we got a completely different result (The first picture below) The cylinder and point are given the same coordinates, however the cylinder a couple hundred meters southwest and below the point. We've been looking through our code base for some weird configuration that would make the cylinder appear like that but we havent found anything. [image: image.png] [image: image.png] Here's the code we used to render both images: const greenCylinder = viewer.entities.add({ name: "Green cylinder with black outline", position: Cesium.Cartesian3.fromDegrees(-111.78852417809316, 40.658894298281034, -500), cylinder: { length: 500.0 * 2, topRadius: 794.0, bottomRadius: 794.0, heightReference: Cesium.HeightReference.RELATIVE_TO_TERRAIN, material: Cesium.Color.RED.withAlpha(0.5), }, }); const whitePoint = viewer.entities.add({ name:"White point", position: Cesium.Cartesian3.fromDegrees(-111.78852417809316, 40.658894298281034), point: { pixelSize:10, heightReference: Cesium.HeightReference.RELATIVE_TO_TERRAIN, color: Cesium.Color.WHITE, }, });

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On Fri, Apr 5, 2024 at 7:35 AM Gabby Getz ***@***.***> wrote: Gotcha @parker-the-king <https://github.com/parker-the-king>. Is it possible to use RELATIVE_TO_GROUND and offset the height by the half the height of the cylinder (500m in this case)? — Reply to this email directly, view it on GitHub <#11921 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AK2UXVWAHX7APAAOBTNPTM3Y32SBFAVCNFSM6AAAAABFWDW3C6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDAMZZHAZDEOBSGM> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[parker-the-king]

After more testing, we've learned that for the cylinders on our app, if we leave out the heightReference: Cesium.HeightReference.RELATIVE_TO_TERRAIN line of code, the cylinder is no longer off center.

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On Tue, Apr 9, 2024 at 10:55 AM Parker King ***@***.***> wrote: We tried what you said in the sandbox and it worked perfectly.(Pictured in the second picture below) Then we copied the exact same code into our application and for some reason we got a completely different result (The first picture below) The cylinder and point are given the same coordinates, however the cylinder a couple hundred meters southwest and below the point. We've been looking through our code base for some weird configuration that would make the cylinder appear like that but we havent found anything. [image: image.png] [image: image.png] Here's the code we used to render both images: const greenCylinder = viewer.entities.add({ name: "Green cylinder with black outline", position: Cesium.Cartesian3.fromDegrees(-111.78852417809316, 40.658894298281034, -500), cylinder: { length: 500.0 * 2, topRadius: 794.0, bottomRadius: 794.0, heightReference: Cesium.HeightReference.RELATIVE_TO_TERRAIN, material: Cesium.Color.RED.withAlpha(0.5), }, }); const whitePoint = viewer.entities.add({ name:"White point", position: Cesium.Cartesian3.fromDegrees(-111.78852417809316, 40.658894298281034), point: { pixelSize:10, heightReference: Cesium.HeightReference.RELATIVE_TO_TERRAIN, color: Cesium.Color.WHITE, }, }); On Fri, Apr 5, 2024 at 7:35 AM Gabby Getz ***@***.***> wrote: > Gotcha @parker-the-king <https://github.com/parker-the-king>. Is it > possible to use RELATIVE_TO_GROUND and offset the height by the half the > height of the cylinder (500m in this case)? > > — > Reply to this email directly, view it on GitHub > <#11921 (comment)>, > or unsubscribe > <https://github.com/notifications/unsubscribe-auth/AK2UXVWAHX7APAAOBTNPTM3Y32SBFAVCNFSM6AAAAABFWDW3C6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDAMZZHAZDEOBSGM> > . > You are receiving this because you were mentioned.Message ID: > ***@***.***> >

[ggetz]

Thanks for the update @parker-the-king. So the fundamental issue is that clamp to ground for cyllinders behaves slightly differently than the rest of the geometries? Or was this specific behavior tied to your app configuration? In the later case, I think the issue can be closed.

[parker-the-king]

I'm not sure if it's a problem with they cylinder itself or something to do with our app. I ended up just using an extruded ellipse instead of a cylinder and it worked perfectly for some reason.

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On Thu, Apr 11, 2024 at 11:21 AM Gabby Getz ***@***.***> wrote: Thanks for the update @parker-the-king <https://github.com/parker-the-king>. So the fundamental issue is that clamp to ground for cyllinders behaves slightly differently than the rest of the geometries? Or was this specific behavior tied to your app configuration? In the later case, I think the issue can be closed. — Reply to this email directly, view it on GitHub <#11921 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AK2UXVT4FKKHE7OUSYEMBTTY43BBXAVCNFSM6AAAAABFWDW3C6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDANJQGE2TOMRQGA> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[parker-the-king]

In sandbox everything works so i'm thinking it might just be some weird thing with our application

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On Thu, Apr 11, 2024 at 11:23 AM Parker King ***@***.***> wrote: I'm not sure if it's a problem with they cylinder itself or something to do with our app. I ended up just using an extruded ellipse instead of a cylinder and it worked perfectly for some reason. On Thu, Apr 11, 2024 at 11:21 AM Gabby Getz ***@***.***> wrote: > Thanks for the update @parker-the-king > <https://github.com/parker-the-king>. So the fundamental issue is that > clamp to ground for cyllinders behaves slightly differently than the rest > of the geometries? Or was this specific behavior tied to your app > configuration? In the later case, I think the issue can be closed. > > — > Reply to this email directly, view it on GitHub > <#11921 (comment)>, > or unsubscribe > <https://github.com/notifications/unsubscribe-auth/AK2UXVT4FKKHE7OUSYEMBTTY43BBXAVCNFSM6AAAAABFWDW3C6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDANJQGE2TOMRQGA> > . > You are receiving this because you were mentioned.Message ID: > ***@***.***> >

[ggetz]

Got it, glad you found a solution! I'm going to close this issue then. Thanks!