[vtk] correction of the texture serialization

[xavArtley]

fixes : #350

However when renderding the vtkjs panel the texture does not appear unless an interaction is done
I tried to export the vtkjs file into the official scene explorer (https://kitware.github.io/vtk-js/examples/SceneExplorer.html) and the same issue arise

May be we need to open an issue on the main repo

[codecov-io]

Codecov Report

Merging #355 into master will not change coverage.
The diff coverage is 0%.

@@           Coverage Diff           @@
##           master     #355   +/-   ##
=======================================
  Coverage   86.99%   86.99%           
=======================================
  Files          88       88           
  Lines        7746     7746           
=======================================
  Hits         6739     6739           
  Misses       1007     1007

Impacted Files	Coverage Δ
panel/pane/vtk.py	30.32% <0%> (ø)	⬆️

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[jourdain]

I guess a call to render is missing when images have been downloader+decoded and connected to the pipeline. You could solve that issue, by triggering a render() call via a timeout.

[xavArtley]

How long should be the timeout?

I guess a call to render is missing when images have been downloader+decoded and connected to the pipeline. You could solve that issue, by triggering a render() call via a timeout.

[jourdain]

Can you point me to the section of code that do the loading. I might be able to provide a better solution than a timeout with a more appropriate callback.

Otherwise you can simply do:

setTimeout(rw.render, 100);
setTimeout(rw.render, 500);
setTimeout(rw.render, 1000);

[xavArtley]

https://github.com/pyviz/panel/blob/67b90c42cb382c38d2ae5355f46d6bfdb217d0d3/panel/models/vtk.ts#L85-L97

[jourdain]

The onReady will be called several time (on for each dataset) so this could be good.
The setURL also return a promise, although image loading/decoding is indeed trickier to properly capture when everything is ready.

Can you try that?

const fn = macro.debounce(() => setTimeout(this._rendererEl.getRenderWindow().render, 100), 100);
sceneImporter.setUrl('index.json').then(fn);
sceneImporter.onReady(fn);

[xavArtley]

Uncaught (in promise) TypeError: Cannot read property 'then' of undefined
at Object.callback (:663:57)
at VM57184 vtk.js:7

setUrl return undefined apparently. However if I use just

const fn = macro.debounce(() => setTimeout(this._rendererEl.getRenderWindow().render, 100), 100);
sceneImporter.setUrl('index.json')
sceneImporter.onReady(fn);

it seems to work

[jourdain]

Great!

[banesullivan]

This is awesome, thanks @xavArtley!

Once this is merged could there be a release staged for panel? As soon as this is available on conda, I could update all of these examples and get the vtki examples on Binder to utilize all your work!

[philippjfr]

Once this is merged could there be a release staged for panel?

I'm happy to cut a dev release, a real release is still waiting on a new bokeh release which should be very soon.

[philippjfr]

Thanks for the fix @xavArtley!