OBJLoader2 and OBJLoader2Parallel V3.0.0-beta2

[kaisalmen]

This addresses #16688 and it brings back worker based parsing via OBJLoader2Parallel and independent WorkerExecutionSupport.

POIs:

• OBJLoader2Parallel extends OBJLoader2 and runs the parser inside a worker. Nothing the old version didn't do.
• It now either uses some of the modules from obj2 to build the worker code or it uses OBJLoader2Worker to directly feed a module into the Worker both via WorkerExecutionSupport. This feature is only experimentally available in Chrome and no other browser as far as I know. It is beautifully simple that's why I put it in already. See for yourself:

import { OBJLoader2Parser } from "../OBJLoader2Parser.js";
import {
	WorkerRunner,
	DefaultWorkerPayloadHandler
} from "../WorkerRunner.js";

new WorkerRunner( new DefaultWorkerPayloadHandler( new OBJLoader2Parser() ) );

• If no directly loading a jsm module, the new version of WorkerExecutionSupport takes modules loaded into memory and serializes them to a Blob. I wanted to use rollup/babel directly in the browser, but it was always a dead end street. The solution now allows to serialize any module that is available when serialization takes place code (see OBJLoader2Parallel imports imports and OBJLoader2Parallel buildWorkerCode. @donmccurdy this part could be of interest also to you: I want to further modularize WorkerExecutionSupport so you can plug in a standard or own com-protocol on main and worker and are able to use common serialization functions, etc. I will write my ideas down in the Generic Worker Loader issue in the upcoming days.
• Examples are fine now
• Code doc seems fine to me, too

Typescript bindings are missing. Can you hint me to a guide/issue how to approach this? Thank you...

[mrdoob]

Seems like you included three.js builds in the PR by mistake.

[kaisalmen]

Sorry for that. I fixed first commit and force pushed the branch.

[kaisalmen]

This good to go from my side (see updated description). What about the Typescript definitions?

[Mugen87]

What about the Typescript definitions?

I think it's okay if you add it with a different PR. This one is already big and contains many changes.

[kaisalmen]

All LGTM issues are fixed and I updated the description once more. I did it in a rush yesterday.

[mrdoob]

Thanks!

[unphased]

Hi, I'm trying out ES6 modules and r106, I successfully got THREE imported as modules in my code like so:

import * as THREE from 'https://threejs.org/build/three.module.js';
import { OBJLoader2 } from 'https://threejs.org/examples/jsm/loaders/OBJLoader2.js';

The problem that I have is that the loadMtl function has completely vanished from OBJLoader2, so I don't know how to make my code work again. I will start to tie the code to r105 for the time being.

Was hoping you guys could point me in a direction. I wonder if I'm trying to use modules too early.

curl -s https://threejs.org/examples/jsm/loaders/OBJLoader2.js | grep -i loadmtl

gives me no output either.

[kaisalmen]

Hi @unphased please look at the basic example. The decision to remove mtl related functions was taken by me in the last release already (jsm code). I have introduced MtlObjBridge with R105 to not have OBJLoader2 depend on MTLLoader. The basic example shows how to resolve this problem:
https://github.com/mrdoob/three.js/blob/dev/examples/webgl_loader_obj2.html#L59-L61
https://github.com/mrdoob/three.js/blob/dev/examples/webgl_loader_obj2.html#L122-L137

Maybe, we should add something to the migration guide. @Mugen87 what do you think?

[Mugen87]

Good idea. If you can formulate one or two (short) sentences, I'll put it in the migration guide.

[kaisalmen]

What about this? I activated "Allow edits from maintainers", so you can hopefully copy the raw content:


MTL related functions like loadMtl has been removed from OBJLoader2. Please use MTLLoader and MtlObjBridge as shown in basic obj2 example (required imports and load mtl and obj)