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Images E & W of IDL are not displayed concurrently.

Open Scrambled777 opened this issue 1 year ago • 5 comments

Hi,

Images East & West of International Date Line (IDL) are not displayed together in Places view.

Major focus view E/W of IDL will have images displayed, while in other minor focus view no images displayed at the same time.

Attached screenshot for better clarity around this issue:

  1. In, this screenshot only right side (Major area in view) images are displayed Screenshot_20240710_000050-obfuscated

  2. In, this screenshot only left side (Major area in view) images are displayed Screenshot_20240710_000104-obfuscated

Images should be visible on both side of IDL at the same time, like how it is normally displayed in any other Longitude.

Scrambled777 avatar Jul 09 '24 18:07 Scrambled777

Thank you for your bug report and the screenshots to show what is happening. It is interesting to see... and I have no idea why it is doing that. Does the problem occur at every zoom level? If you zoom in more to the international date line then can you see photos either side?

blissd avatar Jul 09 '24 19:07 blissd

Does the problem occur at every zoom level? If you zoom in more to the international date line then can you see photos either side?

Yes, it happens at every zoom level. Zooming in/out doesn't help.

Only reason I can think of that is maybe it's due to Longitude change.

It feels like thumbnail layer is not stitched at IDL and the area in focus get thumbnails shown. So, thumbnail layer displays thumbnail from 179.99* W to 179.99* E. Upon approaching IDL from either direction, the layer limit is reached at 180*E/W. Thumbnails beyond this endpoint of current active layer will not be displayed until that area comes in focus and 2nd layer becomes active.

I can send you couple of pics (privately) on either side of date line, which might help you to troubleshoot. Let me know how?

Cheers.

Scrambled777 avatar Jul 10 '24 04:07 Scrambled777

Thanks for the offer of photos. I don't think I need them as I can reproduce the problem with some photos I have on the west coast of the US and the east coast of Australia, but I'll let you know if I need more photos for testing.

I use the the h3o library for Uber H3 indexing for selecting what thumbnails to display depending on how far they are from the centre of the map, and I use libshumate for rendering the map.

Looks to me that this might be a bug in libshumate, as I can jiggle the map left and right and see the effect of the bug but can also see from the log output that the map hasn't moved far enough to select new thumbnails using h3o.

blissd avatar Jul 10 '24 04:07 blissd

I've had a go using separate layers for thumbnails east and west of the prime meridian, but there was no change in behaviour. I'll have a look at raising a bug with libshumate.

blissd avatar Jul 10 '24 04:07 blissd

I've (finally) raised an issue with libshumate. See https://gitlab.gnome.org/GNOME/libshumate/-/issues/80

blissd avatar Aug 14 '24 10:08 blissd