Fix that data was not rendered when zoomed in too much

[daniel-wer]

The earlier fix caused a regression, because it didn't distinguish between having zoomed in so much that a viewport is covered by only one bucket and a viewport not being visible at all. Both resulted in a height and width of 0 in bucket coordinates. I introduced a new flag which checks the actual viewport width which is a float and, therefore, is only 0 if the viewport is not visible.

URL of deployed dev instance (used for testing):

• https://___.webknossos.xyz

Steps to test:

• Zoom in as much as possible in a dataset -> Data should always be rendered
• I checked (via breakpoint) that the bucket picking is aborted if the 3D view is maximized (to confirm that Fix crashes related to maximizing/minimizing #5746 which was fixed with the code that caused the regression remains fixed)

Issues:

• fixes When zooming in too far, no data is rendered #5755

---

• Updated (unreleased) changelog
• Updated (unreleased) migration guide if applicable
• Updated documentation if applicable
• Adapted wk-connect if datastore API changes
• Needs datastore update after deployment
• Ready for review

[philippotto]

Very elegant fix 👍 Works perfectly, too. The changelog needs an update before merging :)