[fixed] Quality deterioration when resampling to different projection?

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masterofnoroad
Posts: 6
Joined: Sun Mar 07, 2021 7:38 pm

[fixed] Quality deterioration when resampling to different projection?

Post by masterofnoroad » Sun Mar 07, 2021 8:12 pm

Hello

I updated Alpine Quest few days ago to 2.2.8b from the previous version (im always updating when google play asks but dont remember last version number)
and since then noticed change in rendering of my basic topo composition.

Im attaching two screenshots of same area and same composition before and now. If you compare them closely there is loss of details in the recent one. Especially visible if you try to read altitude points. Map is displayed in EPSG:3857 as the first layer is OpenTopoMap. The badly rendered map is Polish EPSG:2180L projection old topographic maps.

The map consists of layers with different projection definitions. If I open just one of them and there is no recalculation needed the rendering improves. So my guess is this is the problem and in recent version something here was changed for worse. It looks like now there is only nearest neighbourhood resampling used and before it was something better?

Working on Android 9 if that changes something...
Attachments
Screenshot_20210307-201132_AlpineQuest Off-Road Explorer copy.jpg
(422.99 KiB) Not downloaded yet
8145a1fd4008729d6bd9b2838f5d210a.0.jpg
(408.59 KiB) Not downloaded yet

Psyberia-Support
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Re: Quality deterioration when resampling to different projection?

Post by Psyberia-Support » Mon Mar 08, 2021 2:56 pm

Hi,
I don't remember changing anything recently on this, but it's hard to tell for sure...
It would be great if you could send me the polish map file I can check it on the various last versions.

For information, long time ago (until version 2.1.1), a kind of anti-aliasing was applied for re-projected maps, but it has been removed because lot of users complained it was making the map looking too blurry. But it was 3 years ago so I don't think it's related to what you see.
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masterofnoroad
Posts: 6
Joined: Sun Mar 07, 2021 7:38 pm

Re: Quality deterioration when resampling to different projection?

Post by masterofnoroad » Mon Mar 08, 2021 5:07 pm

Attaching here The Geoportal Topo WMTS.
I use it with OpenTopo on the bottom and Geoportal in darken mode.
Attachments
Geoportal_TOPO.aqx
(2.06 KiB) Downloaded 101 times

Psyberia-Support
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Re: Quality deterioration when resampling to different projection?

Post by Psyberia-Support » Mon Mar 08, 2021 8:28 pm

Thanks for the file.
I can confirm that there is something different in the latest version. I'll investigate and let you know soon. Sorry for the troubles.
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masterofnoroad
Posts: 6
Joined: Sun Mar 07, 2021 7:38 pm

Re: Quality deterioration when resampling to different projection?

Post by masterofnoroad » Wed Mar 10, 2021 9:01 pm

Ok, no worries. Im happy its not just my imagination :D
Is there an easy way to go back to previous version? Maybe switch some files for old ver. in the phone memory?

Psyberia-Support
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Re: Quality deterioration when resampling to different projection?

Post by Psyberia-Support » Thu Mar 11, 2021 7:58 pm

No unfortunately there is nothing you can do with the current version.
But by tomorrow I'll publish a fixed beta version, you can request beta versions from the Play Store, in the application section.
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Re: Quality deterioration when resampling to different projection?

Post by Psyberia-Support » Fri Mar 12, 2021 12:47 pm

I've published beta version 2.2.8c.r6921, in which this issue should be fixed.
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masterofnoroad
Posts: 6
Joined: Sun Mar 07, 2021 7:38 pm

Re: Quality deterioration when resampling to different projection?

Post by masterofnoroad » Tue Mar 16, 2021 10:27 pm

Now its fine! Thanks for the support! Your app is amazing!

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Re: [fixed] Quality deterioration when resampling to different projection?

Post by Psyberia-Support » Wed Mar 17, 2021 11:03 am

Great, thanks for the feedback.
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