mapbox / mapbox/mapbox-gl-js

How to display undistorted vector data around poles

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bug :lady_beetle:
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TypeScript
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Description

**mapbox-gl-js version**: 2.11.0

### Question

How to display undistorted vector data around poles? Ideally I would like to display raster tiles or MVT tiles or GeoJSON around poles. I know that with tiles (neither vector no raster) it is not possible because of limitations of web-mercator that tiles assume. The tiles use "slippy tile" indexing scheme, which in turn assumes web-mercator projection, which does not work above 85 (below -85) latitude).

But GeoJSON layer do not have the constraints of tiles. Sadly, when I try to render anything around poles, I get distorted results (similarly as [in this bug](https://github.com/mapbox/mapbox-gl-js/issues/12026))

Examples of distortions near poles (based on [this example](https://docs.mapbox.com/mapbox-gl-js/example/geojson-polygon/)):

image (2)

image (1)

image

### Links to related documentation
- https://docs.mapbox.com/mapbox-gl-js/guides/projections/

Contributor guide

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First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start with the GeoJSON polygon example and the projections guide linked in the issue, then compare the reported behavior with related issue #12026. Investigate how GeoJSON layers are rendered near the poles and determine whether the requested raster, MVT, or GeoJSON behavior fits the current projection design. Done means a documented or implemented way to display this data without the reported distortion.

Written by the indexing model from the issue text.

Assessment

Tech stack
typescript
Domain
computer-graphics, frontend, web-dev
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
25/100

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