made with the ArcGIS Maps SDK for JavaScript, Node.js and ESP32.
Send the map legend to a RGB LED strip like here!
Use this ESP32 firmware to receive data from artnet-http and put it on your LED strip via FastLED.
You can use my fork of Dewb's artnet-http project to run a small Node.js application on localhost that receives data from the map, transforms it into Artnet and sends it over to the ESP32.
This is the webmap with logic for legend2LEDs.