Can Three.js loaders accept an AbortSignal for cooperative cancellation?

Answer

No, the standard Three.js loader classes (e.g., GLTFLoader, TextureLoader, FileLoader) do not accept an AbortSignal argument in their constructors or load methods.

Why

Loaders rely on the callback‑based API (onLoad, onProgress, onError) and internally use either XMLHttpRequest or the Fetch API via a private FileLoader. That internal loader does not expose a way to pass an AbortSignal to the underlying network request, so there is no built‑in cooperative cancellation mechanism.

What you can do today

1. Wrap the loader call in your own Promise that resolves/rejects based on the loader’s callbacks and manually checks an AbortSignal. If the signal is aborted, ignore the loader’s result and dispose of any partially created Three.js objects.
2. If you are using a version of Three.js that ships with a fetch-based FileLoader (r110+), you can subclass FileLoader and override its load method to accept an AbortSignal and pass it to fetch. This requires maintaining a custom loader subclass.
3. LoadingManager does not propagate abort signals to its child loaders; you would need to forward the signal manually to each loader you create.

Verification steps (safe, scoped)

// 1. Check the current FileLoader source (no build step)
fetch('https://unpkg.com/three@0.152.2/build/FileLoader.js')
  .then(r => r.text())
  .then(txt => {
    console.log(/AbortSignal/.test(txt) ? 'Found' : 'Not found');
  });

Replace the version in the URL with the one you are using. A “Not found” output confirms the lack of native support.

Missing diagnostic detail

Which Three.js version are you targeting? The internal implementation switched from XMLHttpRequest to Fetch around r110, affecting how a custom abort solution would be implemented.