Small blog post on blending https://oliverwipfli.ch/canvas-multiply-blending-2025-11-24/

When you learned to subtract numbers by hand, did you learn it with this "borrowing" method?
I forgot how to subtract say 384 from 2173 and asked some chatbots "how do you subract by hand with pen and paper". They all explain it with this super strange borrowing method. Here in Switzerland I just learned to add a 1 if you cross zero...

Multiply blending is nice for topographic maps, it keeps the greenness of forest much better than normal alpha blending. By coincidence I learned today that multiply blending can help as well for burning gaps around letters into contour lines. Here are some screenshots, code and demo see https://github.com/wipfli/hillshade-multiply-blending

I just remembered that some time ago I vectorized the hand-drawn hillshading of swisstopo and put it on a MapLibre-based map. Demo: https://wipfli.github.io/swiss-map/vector-hillshade#map=10.14/46.8474/9.5298

OSM highways at z6 in Switzerland

Removing small loops from Planetiler's intermediate rendering output can improve linestring merging, read more here: https://oliverwipfli.ch/improving-linestring-merging-in-planetiler-2024-10-30/

The Protomaps basemap supports now 41 languages, including all 24 official languages of the EU. Have a look at https://maps.protomaps.com and select different languages with the dropdown menu.

Swisstopo flag in Ebnat-Kappel, Switzerland.