TypeError: Cannot read properties of null (reading 'point')

[wipfli]

maplibre-gl-js version: 5.3.0

browser: Ubuntu on chrome

Steps to Trigger Behavior

1. https://jsbin.com/tecogivebe/edit?html,output
2. click zoom out button
3. observe error in console

Link to Demonstration

https://jsbin.com/tecogivebe/edit?html,output

Expected Behavior

Does not throw an error and does render the map on zoom out

Actual Behavior

Throws and does not render

[wipfli]

The error is triggered here: https://github.com/maplibre/maplibre-gl-js/blame/b90b28d1be120314a9f28ab30b68865c5650e890/src/symbol/projection.ts#L505

placeGlyphAlongLine can return null, then in the above line we try glyph.point when glyph is null. I guess it is good that the error is produced.

I compared versions and it looks like since v5 we have this error. In v4.7.1 the error is not thrown, however, already in v4 glyph can be null. Did we change some error handling of placeGlyphsAlongLine when going to v5?

[wipfli]

In v4 the error was not thrown, however, sometimes the map renders and sometimes not on zoom out of the above example. What always happens is that the labels blink on zoom out. I think the correct behavior should be to not show a label at all if one of the glyphs cannot be placed. What do you think?

[HarelM]

I see that the code around that was changed as part of the globe changes, probably due to how globe present labels.
It should not throw in any case, but I tend to agree it should not present a label if glyphs can't be placed.