#cahillconcialdi — Public Fediverse posts

Because today is the June #solstice, here is my 2020 animated map of this solstice’s day-night cycle rendered using the #CahillConcialdi map projection, which is my most favorite.

Grab the file here: https://commons.wikimedia.org/wiki/File:Cahill%E2%80%93Concialdi_projection_(Natural_Earth_I)_day-night_animation_at_June_solstice.gif

#maps #cartography #Mapstodon #gischat

#30DayMapChallenge 🗺️ Day 2️⃣6️⃣: Map projections

I could’ve created another #CahillConcialdi map since that’s my favorite projection, but because I already made a couple of those earlier this month and since the idea is to explore other map projections, I decided to finally try implementing an idea I’ve had for a while, which is to project the whole world onto my favorite geometric shape, the #RhombicTriacontahedron!

Why this shape? Read this: https://vaes9.com/posts/rhombic_triacontahedron

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#30DayMapChallenge 🗺️ Day 1️⃣2️⃣: Time & space

I kept it simple and did an animation of #NASA’s Blue Marble Next Generation series which depicts Earth’s landcover for each month of 2004:

https://earthobservatory.nasa.gov/features/BlueMarble

I used my #CahillConcialdi renderer to reproject the 12 images from the original plate carrée projection, then went into @kdenlive to create an 18-second video.

The most obvious change is the north hemisphere snow, but the rest of the world has subtle changes in vegetation.

#Kdenlive

#30DayMapChallenge 🗺️ Day 6️⃣: Raster

If you know me or have seen my maps from last year, you know that my most favorite projection is the #CahillConcialdi.

So for today, I modified my Cahill–Concialdi tool’s¹ raster processor to reproject the 1943 two hemispheres world map from the #NationalGeographic Society (2nd map) that is in a polar azimuthal equidistant projection.

While the labels are now messed up (and mostly upside down), I do think the map is still pretty! 🤩

¹ https://github.com/seav/cahill-concialdi

Finally tried #OpenAI’s GPT-4o chatbot and asked it about my go-to LLM topic (my favorite #CahillConcialdi map projection). It gave a factually incorrect answer. 🤷

#AI #LLM #GPT4o

Data sources:
▪︎ Country polygons from #NaturalEarth’s 1:50m cultural vectors
▪︎ Antarctic country data scraped from #Wikipedia

Tools used:
▪︎ My #CahillConcialdi renderer: https://github.com/seav/cahill-concialdi
▪︎ #GIMP for creating labels, legends, and final touches

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#30DayMapChallenge 🗺️ Day 2️⃣5️⃣: #Antarctica 🇦🇶

I wonder if I can get away with making a map about Antarctica but without showing any part of it! 😉

I managed to do just that by showing how involved the countries of the world are in the coldest continent! (Again I used my favorite #CahillConcialdi map projection—any guesses as to what I’ll be doing for Day 30? 😂)

The countries are classified along 4 axes...

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#30DayMapChallenge 🗺️ Day 2️⃣1️⃣: Raster

(Still catching up!)

So I’m back again with my favorite #CahillConcialdi map projection! I already had the code to reproject plate carrée source images and also Web Mercator tiles into my fave projection. I additionally had some code to composite 2 separate images based on the current day/night sides of the Earth. But I didn’t yet have the code to combine Web Mercator tiles with the day and night compositing. So I that’s what I did for Day 21’s theme!

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#30DayMapChallenge 🗺️ Day 1️⃣3️⃣: #Choropleth

(Finally caught up!)

For today, I wanted to do something simple and whimsical.

There’s a lot of rumblings online because Taylor Swift’s wildly successful The Eras Tour is not coming to this or that country. So while I’m not a Swiftie, here’s a map (in my favorite #CahillConcialdi projection) showing which 20 countries currently have tour dates. As you can expect, the usual countries are there and Africa is noticeably absent.

#TaylorSwift #TheErasTour

#30DayMapChallenge 🗺️ Day 3️⃣: Polygons

Here are the world’s time zones rendered in my favorite #CahillConcialdi projection. Each zone is colored based on its offset from UTC mapped to the color spectrum 🌈. If a region observes daylight saving, the color is based on the average of the summer and winter time.

This is inspired by a similar map created by Emīls Rode and Oskars Weilands for the Dymax Redux competition organized by the Buckminster Fuller Institute in 2013: https://mapsontheweb.zoom-maps.com/post/134062804597/timezones-by-emils-rode-and-oskars-weilands-one

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Current daylight/nighttime map of the Earth using a #CahillConcialdi (aka bat) #MapProjection.

What’s this projection? https://github.com/seav/cahill-concialdi/

#MappyMondays

Current daylight/nighttime map of the Earth using a #CahillConcialdi (aka bat) #MapProjection.

https://github.com/seav/cahill-concialdi/