Edit API for `SingleThreadedFragmentsModel`

[ShaMan123]

Description 📝

I want to be able to use the edit API on node.
I understand that Using FragmentsModel and Editor are not supported on node due to the Worker class.
https://github.com/ShaMan123/engine_fragment/blob/1cc799b15fb0110e8a33c0eb3617ab3980911661/packages/fragments/src/FragmentsModels/src/model/fragments-model.ts#L204

Suggested solution 💡

No response

Alternative ⛕

None

Additional context ☝️

No response

Validations ✅

• Read the docs.
• Check that there isn't already an issue that requests the same feature to avoid creating a duplicate.

[agviegas]

Hey @ShaMan123 , good point. The edit logic itself is pure flatbuffer manipulation, it lives on VirtualFragmentsModel.edit() and doesn't need the Worker. SingleThreadedFragmentsModel just never exposed wrappers for it.

Just pushed a fix that adds the full edit API to SingleThreadedFragmentsModel:

import { SingleThreadedFragmentsModel, EditRequest } from "@thatopen/fragments";

const model = new SingleThreadedFragmentsModel("my-model", buffer);

// Apply edits
const { deltaModelBuffer, ids } = model.edit(editRequests);

// Or flatten accumulated edits into a new committed buffer
const newBuffer = model.save();

// History navigation
model.undo();
model.redo();
model.selectRequest(index);
const { requests, undoneRequests } = model.getRequests();
model.setRequests({ requests, undoneRequests });
model.reset();

The API surface matches the multithreaded FragmentsModel/Editor, with one behavioral difference: in the browser flow, applying edits also loads the delta buffer back as a separate scene-attached FragmentsModel for live rendering. There's no scene in Node, so edit() just returns the delta bytes, you do whatever you want with them (persist, send to a client, process further, etc.). save() returns the fully-committed buffer same as before.

Let us know if anything's missing for your use case! Available from the next patch 3.4.4.

[ShaMan123]

Wow! Great!

[ShaMan123]

This will complement #164

[ShaMan123]

I am getting errors trying to use this feature.
Incorrect header check or malformed fragments data, depending if I flip the raw flag when loading the fragment buffers

const model = new SingleThreadedFragmentsModel("my-model", buffer);
const newBuf = model.save();
new SingleThreadedFragmentsModel("my-model", newBuf); // fails
new SingleThreadedFragmentsModel("my-model", newBuf, true); // succeeds