[Deck.gl.Polygon] MultiplePolygon are not visible

[xavier-GitHub76]

Bug description

Hello,

I build a dataset with polygons (GeoJSON) but multiple polygons are not visible on Deck.gl.Polygon chart.

I reduce the dataset, it has only 2 departements :

• 'Deux-Sèvre' (build with a unique polygon)
• 'Charente-Maritime' (build with a multipolygon)

The unique polygon is visible but
only one of multiples polygons is visible.

All polygons are visible with https://mapshaper.org
but not with Superset

Dataset is built with insert_DEPARTEMENT_(genereted).sql from DEPARTEMENT.json

insert_DEPARTEMENT_(genereted).zip

DEPARTEMENT.json

Regards

Screenshots/recordings

No response

Superset version

4.0.2

Python version

3.9

Node version

16

Browser

Chrome

Additional context

No response

Checklist

• I have searched Superset docs and Slack and didn't find a solution to my problem.
• I have searched the GitHub issue tracker and didn't find a similar bug report.
• I have checked Superset's logs for errors and if I found a relevant Python stacktrace, I included it here as text in the "additional context" section.

[dosubot]

I found a similar unsolved discussion that might be relevant to your issue: Insert a Multipolygon into a Deck.gl Polygon chart, which was last updated on December 11, 2024 ^[1].

For your specific issue with multipolygon visibility in Superset, here are a few steps you can take to troubleshoot:

1. Check GeoJSON Format: Ensure that the GeoJSON for the multipolygon is correctly formatted. Each polygon in a multipolygon should be an array of linear rings, where the first ring is the outer boundary and any subsequent rings are holes.

2. Superset Configuration: Verify the configuration options in Superset's Deck.gl Polygon layer. Make sure that the "Polygon Column" and "Polygon Encoding" settings are correctly set to handle multipolygon data ^[2].

3. Simplification and Export: If you are using Mapshaper to simplify the polygons before importing them into Superset, ensure that the simplification process is not removing small features that are necessary for the multipolygon to render correctly.

4. Logs and Errors: Check Superset's logs for any error messages that might indicate issues with rendering the multipolygon data.

These steps should help you identify and resolve the visibility issue with your multipolygon data in Superset.

To continue talking to Dosu, mention @dosu.

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[paridbushati]

I have the same problem where only one polygon is visible and still haven't found a solution! @xavier-GitHub76 Have you found a solution in the meantime?

[xavier-GitHub76]

For my part, I avoid the problem by playing with the precision of the map (with https://mapshaper.org) so that the smallest areas are erased.
It's not a good solution