Native Support for Alternate Geospatial CRS (EPSG:4326)?

[jfuehner]

Hi!

Over the past ~year I have made multiple unsuccessful attempts (5607 , 6090) at trying to leverage CRS EPSG:4326 tile sources with deck in a geospatial capacity.

Was curious what the process is to nominate a feature request to prioritize adding native support for alternate geospatial CRS’ other than EPSG:3857? Namely adding support to MapController/MapView to support EPSG:4326?

When working on attempt 6090 @Pessimistress made mention of this RFC (https://github.com/visgl/deck.gl/blob/master/dev-docs/RFCs/proposals/projection-mode-improvements-rfc.md) from 2017.

When working on attempt 5607 @kylebarron mentioned this proposed draft (#5504) as a possibility.

My current solution is less than ideal as I have stood up a MapProxy server that reprojects tiles from EPSG:4326 to EPSG:3857.

Would love to be able to leverage decks MapController/MapView without having to do this reprojection via MapProxy.

Others appear to have expressed similar interest…

#6058

Thanks so much for your consideration and all you are doing creating such an awesome framework.

[Pessimistress]

We have a large feature backlog. I am personally maintaining this project on my own time, so I cannot promise an ETA for this particular feature. Here are things you can do:

• Create a feature request and gather interest from other users. We always try work on features that can benefit the most users, though again, no guaranteed timeline.
• If you are willing to implement this feature yourself, I'm happy to support you either in a discussion thread or the Slack channel. I apologize if I appear to be unresponsive to MapController With OrthographicView? #6090; it seems that you need me to write a significant amount of code for you to proceed, which comes back to the resource issue.
• If you need prioritized technical support for your use case, you or your organization can become a sponsor of the Urban Computing Foundation.

[jfuehner]

@Pessimistress thanks for your response. I don't think I realized you were personally supporting deck on your own time. Its a wonderful project and I am super appreciative of the work you are doing.

I created FR #6217

[BranZhang]

I did some work to make Mapbox and deck.gl support 4326 projection.

online demo, maybe a little slow, because some js files are deployed on Chinese server.
https://jsfiddle.net/little_potato/ocsf4bwt/

I modified Mapbox to support 4326 projection.

aimap.srs = 'epsg:4326';

And I modified deck.gl base on v8.6.5 to support 4326 projection. this file:

<script src="https://location-dev.newayz.com/aimap-gl-js/libs/deck-4326.min.js"></script>

mostly change functions about projection between web-mercator and lnglat.

[Baruch-G]

Thanks for sharing!
Any chance you have those Deck.gl modifications based on later versions ?

[amuedespacher]

Hi @BranZhang , any chance you could share the source code of your adaptations to make deck.gl render in a projection other than web mercator?

[BranZhang]

@Baruch-G , @amuedespacher , my pleasure, I will share my source code and white a blog about 4326 projection. wait me about 1~2 week.

[BranZhang]

@Baruch-G , @amuedespacher , 😊my code: https://github.com/BranZhang/deck.gl

[amuedespacher]

Thank you, @BranZhang ; I'll have a look at it

[BranZhang]

When I modified deck.gl for supporting 4326 projection, I found this code in 'viewport.js':

get projectionMode() {
    if (this.isGeospatial) {
        // I modified
        return PROJECTION_MODE.WEB_MERCATOR;
        // deck.gl source code
        // return this.zoom < 12
        //   ? PROJECTION_MODE.WEB_MERCATOR
        //   : PROJECTION_MODE.WEB_MERCATOR_AUTO_OFFSET;
    }
    return PROJECTION_MODE.IDENTITY;
}

@Pessimistress I don't understand why projection mode changed to mercator-auto-offset when the map zoom level bigger than 12?
looks like for a higher display precision?

[ibgreen]

https://medium.com/vis-gl/how-sometimes-assuming-the-earth-is-flat-helps-speed-up-rendering-in-deck-gl-c43b72fd6db4

[BranZhang]

@ibgreen , thanks, very helpful.