visgl / visgl/deck.gl

[Bug] Distorted bitmap in LNGLAT coordinate system in Globe view near the poles

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#7,104 4 comments 0 reactions 1 assignee View on GitHub

@Pessimistress is already working on this.

Since Jun 29, 2022.

bug
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Description

Description

Using example image linked from LNGLAT coordinate system docs in Globe view, the bitmap is visibly distorted near the poles in the longitude direction. It looks like the bitmap is split into 36 segments, 10 degrees longitude wide each.

The image projection is EPSG:4326 which should be compatible with deck's LNGLAT.

Screenshot 2022-06-28 at 20 19 14

I'm not sure what's the cause. Is it possible that there is a missing coordinate conversion in bitmap-layer.ts#L325 to project the image into deck globe mesh?

The issue is more apparent with weather float data, rendered as contours. The distortion results in discontinuous contours. I can provide a sample data file if needed, but solving the issue for the example image above should solve it also for this case.

Screenshot 2022-06-28 at 21 22 46

Flavors
  • React
  • Python/Jupyter notebook
  • MapboxLayer
  • GoogleMapsOverlay
  • CartoLayer
  • DeckLayer/DeckRenderer for ArcGIS
Expected Behavior

Bitmap without visible distortion near the poles.

Steps to Reproduce

Use example image linked from LNGLAT coordinate system docs in Globe view. Rotate to the poles to see the distortion.

https://codepen.io/zakjan/pen/MWQNzLR

Environment
  • Framework version: 8.7.12
  • Browser: any
  • OS: any
Logs

No response

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