Nelson's word is 'music', and the 11 Inktober 2019 prompt was 'snow'. I googled snow music which turns out to be a song by Lynne Rae Perkins with a pretty snow globe in the illustration so I drew that…

There’s something called a ‘hex crawl’, which like a dungeon crawl is mapping and logging events in a roleplaying exercise; I say that because it’s mostly about rolling dice and deciding which way to go or look. The triangle fans which I have been pushing out at a vertex of a shape in some ways approximates an explorer traveling and mapping some terrain. Starting with the area within the observable radius, a circle around the observer, you push out the known territory by going to the perimeter and looking. There is an arc of observed territory beyond the previously mapped territory. The explorer can follow the course of a river and trace out the branching tributaries, noting the biomes and terrain, forests, hills, mountains, desert, etc. A ship might trace the coastline in the same way, hugging the coast and looking, or landing and exploring the inland territory. You just need to make up some rules and random tables for rivers, terrain and biomes.

For example, is there a river? If there is, where does it come from and where does it go? Does it start in this space? Does it branch in this space? If it exists, the river exits at some point. If it doesn’t originate in this space, where does it come from? If it branches, where do the branches enter, join and exit as a bigger river? These arcs are triangle fans made by pushing out a vertex, but the space is best converted into a lopsided circle or ellipse with a complete triangle 'wheel' surrounding a center point. This is where a river originates if it originates in this space and then flows out one of the vertices. This is where the inflow connects, or several inflows connect, with the enhanced outflow.

For example, is there a river? If there is, where does it come from and where does it go? Does it start in this space? Does it branch in this space? If it exists, the river exits at some point. If it doesn’t originate in this space, where does it come from? If it branches, where do the branches enter, join and exit as a bigger river? These arcs are triangle fans made by pushing out a vertex, but the space is best converted into a lopsided circle or ellipse with a complete triangle ‘wheel’ surrounding a center point. This is where a river originates if it originates in this space and then flows out one of the vertices. This is where the inflow connects, or several inflows connect, with the enhanced outflow. This happens even in cases where we close a concavity with a single triangle!

The vertex we’re trying to push has two neighboring vertices, clockwise and counterclockwise and up to three new vertices, zero in the case of a triangle closing a concavity, one at some distance and several more based on whether the edges connecting this initial outlying point are too long and need to be subdivided, generally adding one or more more outlying points in a rough arc of points and new edges roughly the same distance from that initial vertex we chose to push out. This all goes into a counterclockwise list for that lopsided triangle wheel (and polygon) and the new outer perimeter segment gets spliced into the list of points making up the total map polygon.