Here are some scripts to generate low-resolution, tileable map images with Dr. F. Landis Markley’s projection (1982).
See https://observablehq.com/@fil/markley for more infomation about Markley’s projection.
grid.js inverts grid points to latitudes and longitudes and write to grid.jsonl.
generate_map.py loads grid.jsonl and calculates the heightmap of a hemisphere from GEBCO_2021 data.
This takes a few hours to finish. Generated heightmaps are saved as heightmap_east.npy and heightmap_west.npy.