Zoom 17 missing some building parts

[mjcunningham]

Go to: http://tangrams.github.io/bubble-wrap/#18.87804/40.74546/-73.99049

Note bump on southern side of the building below the waldy's woodfire pizza label:

Zoom out once: http://tangrams.github.io/bubble-wrap/#17.87804/40.74546/-73.99049

Note that the bump is gone:

Zoom out again: http://tangrams.github.io/bubble-wrap/#16.87804/40.74546/-73.99049

The bump has returned.

This happens on web and on ES

[rmarianski]

This the osm way in question? http://www.openstreetmap.org/way/287494678

Possibly related to #653? Although, it does show up in the tile with a min_zoom of 16, assuming that is indeed the way.

Not sure why the bump would be disappearing at z17 and appearing at z16. I'd expect it to start showing at z17+ if anything. Could there be a rule on the styling side controlling that @nvkelso?

[zerebubuth]

I've added a test for whether the data is present in the tiles, which passes. That suggests that @rmarianski is right and client-side filtering is playing a role.

I think it might be in the extrusion filtering, as there's a min-height rule at zoom 16, but no min-height rule at 17. This feature has a height of 111, so is included at 16, but the area and volume rules are not triggered at 17.

I think that's what's happening - if I'm understanding the rules correctly!

[rmarianski]

And looking at the requests made out to the server, only requests for z16 are made and then they are "overzoomed".

[nvkelso]

From that chunk of code:

                    - { $zoom: [16], height: { min: 100 } }
                    - { $zoom: [16], area: { min: 3500 } }
                    - { $zoom: [16], volume: { min: 50000 } }
                    - { $zoom: [17], area: { min: 500 } }
                    - { $zoom: [17], volume: { min: 15000 } }
                    - { $zoom: { min: 18 } }

We think something like this needs to be added to zoom 17 filter set:

                    - { $zoom: [17], height: { min: 100 } }

[nvkelso]

Closing this in favor of tangrams/bubble-wrap#187.