Adding Lakes Equatorial and/or Transverse Mercator

I’ve forked a world map and altered it’s projection here:

I have been able to adjust the graticule and projection type without any trouble. What I seem unable to do is add lakes. I have tried creating my own json from the natural earth site using mapshaper and attaching it ipo of where it is fetching the 110m.json. This does allow me to var a “lakes” just like the “land” and “countries”, but the lakes do not show, and the fill for the my countries goes haywire.

All I’m needing is code exactly like I have completed so far, but with lake borders/fill added.

Please help.

Thank you, Lisa Drapeau

No need to reply. I believe I have figured it out meshing this observable with what I already had:

So now if you go to my initial observable, you can see the waterway outlines there. Lower resolution gson can be created (50m, 110m) can be made from natural earth.


Thank you for also sharing the solution in case anyone else gets stuck with a similar problem! (relevant XKCD)

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Fun comic!

Here’s a related thread:

… I don’t really know all that much about any of this, just FYI. :wink:

Thank you everyone. And if you go to my account at:

you will see that I have these maps in both Transverse Mercator and Transverse Equatorial in both PNG exportable and SVG exportable notebooks. The coding is a little different in each.

The purpose of having both is I ran into need to be able to export SVG, that I could then ungroup in inkscape, and save as DXF to then open in any CAD program. I’m planning to take the DXFs and prep them for being cut on a laser cutter to make a layered “interrupted” version of the maps to hang on my wall. I was inspired by Jason Davies interrupted transverse mercator page here:

My “real world” versions will have layers of lasercut plywood much the same way he has layered with the different colors on his webpage, with some parts like the graticule being etched and not actually cut. I know it may not be relevant within observablehq itself, but I will post an instructable or something explaining the whole process once I have them complete. I figure there may be other people on here beside me that are looking for ways to easily code a map projection, and take it all the way into something laser cut and/or cnc (including going through all of the methods through all of the open source resources to do so).

Thanks again everyone!