Unsupported glTF Extension: KHR_technique_webgl

CesiumJS
1

1. A concise explanation of the problem you're experiencing.

An error occurred while rendering. Rendering has stopped.
RuntimeError: Unsupported glTF Extension: KHR_technique_webgl
Error
    at new t (http://localhost:8081/Build/Cesium/Cesium.js:444:28523)
    at Object.F.checkSupportedExtensions (http://localhost:8081/Build/Cesium/Cesium.js:493:30361)
    at be.update (http://localhost:8081/Build/Cesium/Cesium.js:496:14415)
    at T.update (http://localhost:8081/Build/Cesium/Cesium.js:505:22252)
    at F.process (http://localhost:8081/Build/Cesium/Cesium.js:511:1152)
    at K (http://localhost:8081/Build/Cesium/Cesium.js:511:29631)
    at G.update (http://localhost:8081/Build/Cesium/Cesium.js:512:4986)
    at a.update (http://localhost:8081/Build/Cesium/Cesium.js:489:10993)
    at et (http://localhost:8081/Build/Cesium/Cesium.js:525:24190)
    at Ze (http://localhost:8081/Build/Cesium/Cesium.js:525:21751)

2. A minimal code example. If you've found a bug, this helps us reproduce and repair it.

I use cesium 1.50 ,load 3DTiles ,then,it errors

3. Context. Why do you need to do this? We might know a better way to accomplish your goal.

4. The Cesium version you're using, your operating system and browser.
cesium1.50 chrome

2

Thanks for reporting this. Did you use Cesium ion to generate this tileset? The extension name is KHR_techniques_webgl, (notice the s), so it sounds like this model might have been generated incorrectly.

3

Hi,

we have the same problem. The cesium implementation changed the extension name from KHR_technique_webgl to KHR_techniques_webgl with the 1.50 release. See: https://github.com/AnalyticalGraphicsInc/cesium/blob/1.49/Source/Scene/ModelUtility.js#L145

So our tilesets we created ourselfs also have the wrong extension name “KHR_technique_webgl” in the tilesets.

Maybe you can keep the KHR_technique_webgl to preserve compatibility with old datasets ?

Thanks,

4

Oh, I didn’t realized the extension was renamed at some point. I couldn’t find a breaking change for this listed, so I brought this up here:

I’ll update this thread back once there’s a resolution, but feel free to follow that issue or chime in there too.

5

Ok, I think the issue here is that even though it was included in the 1.49, it was never officially supported or documented, that’s why there wasn’t a breaking change and deprecation period. Kudos for being on the cutting edge, but sometimes it comes at a price!

From what I can tell, it looks like it’s just not purely a naming issue. The tiles that were generated using the old specification might have unintended behavior. I think it might be easiest to re-convert your models with the latest obj2gltf. Does that work for you all?