Show HN: A Zoomable Equal-Area Map Projection that interpolates to Mercator
20 hours ago
- The UN passed a non-binding resolution encouraging Equal Earth projection over Mercator due to size distortion.
- The author presents a new hybrid projection that is equal-area at global scale and seamlessly transitions to Mercator upon zoom.
- The projection uses a simple mathematical formula: atanh(sin(lat)^a)/a, with a parameter a that tweens between equal-area and conformal.
- Compared to Equal Earth, the new map improves appearance of most countries, except Northern Europe when centered.
- The formula also enables compromise cylindrical projections by adjusting the horizontal axis distortion.
- The author discovered this formula while seeking a nice 2:1 aspect ratio map for a visualization about time on Mars.
- The projection is novel for its simplicity and aesthetic results, and a proof of equal-area property is included.