Examples: Removed webgl_loader_gltf_extensions

[mrdoob]

Description

I think, at this point, these models make gltf look bad 🙈

[Mugen87]

I think it's also better to have examples for showcasing just a single extension rather than webgl_loader_gltf_extensions.

[donmccurdy]

Plenty of other glTF examples without these, agreed! I think this example had become too long/complex to be useful anyway.

[WestLangley]

I also do not think it is a good idea to have use cases (i.e., extensions) hidden behind GUI menu items, because CI will not test it.

[takahirox]

Yeah, webgl_loader_gltf_extensions design was bad for CI test.

Now, some glTF extensions (specular-glossiness, unlit, and lights?) are not in our examples (let me know if I'm wrong). it would be good to somehow test them in test directory instead? (I don't think they are not looking so interesting, that we may not need to make showcasing examples for them.)

[mrdoob]

I've heard they're trying to deprecate specular-glossiness.

[takahirox]

Yeah, glTF has specular extension now. So off topic, I'm personally thinking of moving specular-glossiness extension support to my https://github.com/takahirox/three-gltf-extensions repo.

[donmccurdy]

Now, some glTF extensions (specular-glossiness, unlit, and lights?) are not in our examples

I don't think it is necessary that examples exist for every glTF extension. Creating unit tests for them would be ideal.

The GLB used for https://threejs.org/examples/?q=unreal#webgl_postprocessing_unreal_bloom could probably be switched to unlit though (gltf-transform unlit in.glb out.glb)

I'm personally thinking of moving specular-glossiness extension support to my https://github.com/takahirox/three-gltf-extensions repo.

Let's start an issue about this, there may be a few options and considerations here.

[mrdoob]

The GLB used for https://threejs.org/examples/?q=unreal#webgl_postprocessing_unreal_bloom could probably be switched to unlit though (gltf-transform unlit in.glb out.glb)

That sounds good to me 👍

[donmccurdy]

Hm I tested this out, but it turns out the PrimaryIonDrive.glb model has on emissive effect that we'd lose by switching to unlit, probably better to leave that as-is after all.