`Error displaying widget` for ImageTexture in Textures example with JupyterLab

[elPistolero]

The two ImageTexture objects checker_tex and earth_tex cannot be rendered with jupyterlab. data_tex can be rendered correctly.

With a jupyter notebook everything works as expected.

The console gives the following output:

future.js:155 Uncaught (in promise) Error: Canceled
    at t.dispose (future.js:155)
    at default.js:385
    at Map.forEach (<anonymous>)
    at e.dispose (default.js:384)
    at e.dispose (default.js:244)
    at index.js:241
    at <anonymous>
checkerboard.png Failed to load resource: the server responded with a status of 404 (Not Found)
ImageTexture.js:22 Error loading texture: img/checkerboard.png
bluebird.js:1545 Warning: a promise was rejected with a non-error: [object Event]
    at U (http://localhost:8889/lab/static/main.75a01e1….js:1:109001)
    at A.t._warn (http://localhost:8889/lab/static/main.75a01e1….js:1:103042)
    at A._rejectCallback (http://localhost:8889/lab/static/main.75a01e1….js:1:144410)
    at http://localhost:8889/lab/static/main.75a01e1….js:1:144677
    at http://localhost:8889/lab/static/main.75a01e1….js:1:2017011
    at HTMLImageElement.<anonymous> (http://localhost:8889/lab/static/main.75a01e1….js:1:1368742)
From previous event:
    at A.R [as _captureStackTrace] (http://localhost:8889/lab/static/main.75a01e1….js:1:107952)
    at A._resolveFromExecutor (http://localhost:8889/lab/static/main.75a01e1….js:1:144554)
    at new A (http://localhost:8889/lab/static/main.75a01e1….js:1:137678)
    at i.constructThreeObjectAsync (http://localhost:8889/lab/static/main.75a01e1….js:1:2016837)
    at i.createThreeObjectAsync (http://localhost:8889/lab/static/main.75a01e1….js:1:949721)
    at initialize (http://localhost:8889/lab/static/main.75a01e1….js:1:947950)
    at i.t.Model (http://localhost:8889/lab/static/main.75a01e1….js:1:1900366)
    at i.t [as constructor] (http://localhost:8889/lab/static/main.75a01e1….js:1:2212313)
    at i [as constructor] (http://localhost:8889/lab/static/main.75a01e1….js:1:1918529)
    at i [as constructor] (http://localhost:8889/lab/static/main.75a01e1….js:1:1918529)
    at i [as constructor] (http://localhost:8889/lab/static/main.75a01e1….js:1:1918529)
    at new i (http://localhost:8889/lab/static/main.75a01e1….js:1:1918529)
    at t.<anonymous> (http://localhost:8889/lab/static/main.75a01e1….js:1:2491868)
    at l (http://localhost:8889/lab/static/main.75a01e1….js:1:2487926)
    at Object.next (http://localhost:8889/lab/static/main.75a01e1….js:1:2487257)
    at a (http://localhost:8889/lab/static/main.75a01e1….js:1:2486784)
    at <anonymous>

[vidartf]

Thanks for the report. I'm looking into it, but got side tracked by something else. Which version of jupyterlab and which version of pythreejs are you using?

[elPistolero]

I'm using jupyterlab version 0.31.8 and pythreejs version 1.0.0b6.

I also tried using absolute paths for the png files but that didn't fix the issue.

[vidartf]

Good find! I need to make it a routine to also check all the examples in lab. This best solution to this follows https://github.com/jupyter-widgets/ipywidgets/pull/1993.

[elPistolero]

Interesting. Do you know why absolute paths don't work? Or are relative paths always assumed?

[vidartf]

Do you know why absolute paths don't work?

The texture is supposed to be a URL, so you might have success with an absolute URL.

[elPistolero]

The problem with not displaying absolute URLs seems to be a browser security related issue.

[vidartf]

This is now fixed in master, and will be available with the next release (requires latest version of ipywidgets lab extension).