Improving Mapgen4's boundaries, part 2 #
Last time I mentioned that I made some changes to my dual-mesh helper library. I use it for my Delaunay/Voronoi map and art projects. Part of the motivation was that I want to work on some new map projects, and wanted to fix some of the issues with the library. I then realized I need to test out the changes in mapgen4.
I made a list of mapgen4 bugs I wanted to fix. The main one I'm going to talk about here is that the edges of the map are jagged. Why didn't anyone notice? Because I set the default zoom level to be slightly zoomed in, so that you don't see the edges!
Improving Mapgen4's boundaries, part 1 #
I've been wanting to refamiliarize myself with the mapgen4 code because I'd like to do some new map projects and will want to reuse some of the code from my existing projects.
The first thing I decided to work on was my dual-mesh library. I had originally written it to be a generally useful wrapper around Delaunator. Since then, I wrote the Delaunator Guide, which has all the same functions, but in a way that you can adapt to your own needs. I also realized that by making this library public, I was making it harder for my own needs. So version 3 of this library is going to be primarily for my own needs.
Chaikin Curves #
Sometimes I want to draw Voronoi or similar polygons in a rounded form:
I use a process called Chaikin's Algorithm for this.
Labels: geometry
Square tiling of a sphere, part 3/3 #
In the previous post I described how I learned about the cube/sphere geometry so that I could put a square grid on a sphere. I ended up spending too much time on that, because it turns out the mapping from cube to sphere wasn't as useful as I had thought. This happens to me sometimes, where I find something fascinating, spend a lot of time on it, and it turns out to be not that important.
As the final step in learning how to work with square tiles on a sphere, I wanted to make something on the sphere. I decided to make a dungeon map.
Square tiling of a sphere, part 2/3 #
In the previous post I described how I learned about HEALPix because I wanted to try covering a sphere with square tiles for a game map. During that exploration I realized that HEALPix with 12 square regions is similar to cubes with 6 square regions, but HEALPix has some nice properties for numerical calculations such as spherical harmonics. I don't need those properties. Instead, I am looking for something that's simpler to program, so I explored cubes.
The goal is the same: I want to play a game on a flat top-down tile map (roguelikes, Dwarf Fortress, Factorio, etc.), but these games have one of three approaches to the map:
Square tiling of a sphere, part 1/3 #
I almost always work on 2D game maps, but occasionally I get intrigued by planetary maps. I'd like to make a planet that uses a grid. The topology of a sphere requires a few things:
- Moving east or west you eventually wrap around the world → easy
- Moving north/south you eventually reach a pole, and then all directions are south/north → medium
- Wrapping around the world east/west is shorter near the poles than near the equator → hard
Map generation on a sphere, part 2 #
I spent 9 days working on map generation on a sphere. The first 2 days were geometry: points, triangles, polygons on a sphere. The next 7 days were maps:
- elevation: mapgen4's noise approach looked ok, but I wasn't happy with it, so I switched to using plate tectonics, which looked nice
- moisture: mapgen4's evaporation+wind+rainfall relied too much on a grid, so I wasn't able to use it; I ended up assigning biomes randomly
- rivers: mapgen4's binary tree forest works on graphs, and worked great on a sphere
- rendering: mapgen4's elevation rendering uses outlines and a custom projection which are designed for flat maps, and I wrote a new simple renderer
I wrote up my notes and am going back to working on mapgen4. I'm also putting all the (messy) code up on github.
Map generation on a sphere, part 1 #
I ran into a showstopper with mapgen4. It unpredictably "freezes" in the sense that inputs have no effect, even though both the map generation and rendering are running. I'm taking a break from that for ProcGen 2018 - 9 days to work on a procedural generation project.
I decided to play with procedural map generation on a sphere. I've long wanted to try generating entire planets instead of flat maps. See this project and this project to get an idea of what I'm wanting to learn how to do.
