Support compressed meshes via meshopt

[wrangelvid]

Let's wait on #189 before merging this.

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This change is 

[jwnimmer-tri]

Reviewable status: 0 of 8 files reviewed, 1 unresolved discussion

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src/index.js line 10 at r1 (raw file):

import {GLTFLoader} from 'three/examples/jsm/loaders/GLTFLoader.js';
import {KTX2Loader} from 'three/examples/jsm/loaders/KTX2Loader.js';
import {MeshoptDecoder} from 'three/examples/jsm/libs/meshopt_decoder.module.js';

This file has a different license than threejs (three has vendored it).

The license is suitable and compatible (MIT license), but it does require that we redistribute the license text when we redistribute the code. (See https://github.com/zeux/meshoptimizer/blob/master/LICENSE.md.)

Therefore, somehow or another, we need to get that license text into the THIRD_PARTY_LICENSES.json summary file.

Possibly it would be easier to pull in the decoder directly from our package.json somehow, instead of the three copy? I don't know.

[jwnimmer-tri]

Reviewable status: 0 of 8 files reviewed, 3 unresolved discussions (waiting on @wrangelvid)

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a discussion (no related file):
Digging into the API, I guess this is adding support for the EXT_meshopt_compression extension documented at https://github.com/KhronosGroup/glTF/blob/main/extensions/2.0/Vendor/EXT_meshopt_compression/README.md.

We should at least mention the extension name in the commit message.

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test/meshfile_object_gltf.html line 15 at r1 (raw file):

            var viewer = new MeshCat.Viewer(document.getElementById("meshcat-pane"));

let gltf_contents = `

Meshcat needs to support glTF files both with and without the meshopt compression. Therefore, this PR should add a new test case, not remove any existing test cases.

There is an existing test case meshfile_object_gltf_optimized which was added for testing a different compression extension (KHR_texture_basisu). Now that we have two different compression schemes in play, probably that test case should be renamed for clarity.

[wrangelvid]

Reviewable status: 0 of 10 files reviewed, 1 unresolved discussion (waiting on @jwnimmer-tri)

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a discussion (no related file):

Previously, jwnimmer-tri (Jeremy Nimmer) wrote…

Digging into the API, I guess this is adding support for the EXT_meshopt_compression extension documented at https://github.com/KhronosGroup/glTF/blob/main/extensions/2.0/Vendor/EXT_meshopt_compression/README.md.

We should at least mention the extension name in the commit message.

Done.

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src/index.js line 10 at r1 (raw file):

Previously, jwnimmer-tri (Jeremy Nimmer) wrote…

This file has a different license than threejs (three has vendored it).

The license is suitable and compatible (MIT license), but it does require that we redistribute the license text when we redistribute the code. (See https://github.com/zeux/meshoptimizer/blob/master/LICENSE.md.)

Therefore, somehow or another, we need to get that license text into the THIRD_PARTY_LICENSES.json summary file.

Possibly it would be easier to pull in the decoder directly from our package.json somehow, instead of the three copy? I don't know.

Done.

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test/meshfile_object_gltf.html line 15 at r1 (raw file):

Previously, jwnimmer-tri (Jeremy Nimmer) wrote…

Meshcat needs to support glTF files both with and without the meshopt compression. Therefore, this PR should add a new test case, not remove any existing test cases.

There is an existing test case meshfile_object_gltf_optimized which was added for testing a different compression extension (KHR_texture_basisu). Now that we have two different compression schemes in play, probably that test case should be renamed for clarity.

Done.

[jwnimmer-tri]

This seems good on paper now.

Reviewed 1 of 8 files at r1, 9 of 9 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @wrangelvid)

[jwnimmer-tri]

Reviewed 1 of 1 files at r3, all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @wrangelvid)

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a discussion (no related file):
Working

The Drake bump RobotLocomotion/drake#22935 needs to be approved prior to merging this PR.

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a discussion (no related file):
Working

I need to cross-check that I can repro the minified dist file locally.

[jwnimmer-tri]

Reviewed all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @wrangelvid)