8321/polyline crash

[Samulus]

Fixes #8321

This crash is caused by polyLinesToUpdate becoming out of sync with polyLines. If the position of a polyLine is marked as dirty (i.e .position = .... is invoked) and the polyline is marked for removal, the polyLine will remain in the polyLinesToUpdate array, but not the main polyLines array. The arrays become out of sync and a failure occurs when we try to update a deleted polyLine

Tested on Linux / Nvidia

Test case here: http://localhost:8080/Apps/Sandcastle/index.html#c=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

[cesium-concierge]

Thanks for the pull request @Samulus!

• ✔️ Signed CLA found.
• ❔ CHANGES.md was not updated.
  • If this change updates the public API in any way, please add a bullet point to CHANGES.md.
• ❔ Unit tests were not updated.
  • Make sure you've updated tests to reflect your changes, added tests for any new code, and ran the code coverage tool.

Reviewers, don't forget to make sure that:

• Cesium Viewer works.
• Works in 2D/CV.
• Works (or fails gracefully) in IE11.

[lilleyse]

Nice fix! Mostly small style comments and one larger organizational idea from me.

[lilleyse]

Also, is it possible to find a reproducible test case that could be unit tested?

[mramato]

Awesome work @Samulus.

@tinco can you confirm that this branch fixes your issue?

[tinco]

Epic, I'll try swapping over our production to this release, hopefully there's nothing incompatible going on in master besides this fix :) If it's fixed I should see no more occurrences from today on, I'll know by wednesday next week for sure.

[tinco]

Hm I can't get master to work, something changed with esm, I get errors about not being able to resolve fs and module, which makes sense since we're trying to run this in the browser, but I'm not sure how to fix this. Is this no longer how you use webpack with cesium?: https://gist.github.com/tinco/8f423938bb9dd4fc8edc1fa86ab017b3

[mramato]

@tinco not sure about your setup, but see https://github.com/AnalyticalGraphicsInc/cesium-webpack-example/blob/master/webpack.config.js for a known working configuration with ES6 versions of Cesium. (That whole repository is a standalone example with both debug and release configs, I linked to the debug one I think)

[tinco]

Just tested master on that repo @mramato, it fails there as well, so I guess something really is broken on master for webpack!

[mramato]

@tinco I was unable to reproduce. To avoid derailing this issue, can you write up an issue at https://github.com/AnalyticalGraphicsInc/cesium-webpack-example/issues with details. Thanks!

[Samulus]

Also, is it possible to find a reproducible test case that could be unit tested?

@lilleyse I think that the PolylineCollectionSpec.prototype.update function combined with setInterval is critical to replicating this error. I tried a bunch of different permutations of mutating the collection without calling .update inbetween and couldn't reproduce the same error we see in the Sandcastle demo. Is there a (sane) way of mocking out a frameState in a Jasmine test?

[lilleyse]

Bunch of small suggestions. The new approach looks really clean.

[lilleyse]

Suggested change

	* @default undefined
	* @default false

[lilleyse]

Suggested change

	polylines.update(scene._frameState);
	polylines.update(scene.frameState);

[lilleyse]

Suggested change

	polylines.update(scene._frameState);
	polylines.update(scene.frameState);

[lilleyse]

Oh, and please update CHANGES.md!

[Samulus]

@lilleyse All comments addressed 👍

[lilleyse]

Looks great, thanks @Samulus!