Adapted from:
Lee, Michael and Samet, Hanan. (April 2000). Navigating through Triangle Meshes Implemented as Linear Quadtrees. ACM Transactions on Graphics, Vol. 19, No. 2. Retrieved from https://pdfs.semanticscholar.org/a5c8/8b53174405e5ff512ff5ffa8a56df3c8e2df.pdf
Indices:
/\\ \\--------------/
/ \\ \\ 01 /\\ 11 /
/ 00 \\ \\ / \\ /
/------\\ \\ / 10 \\/
/\\ 10 / \\ \\------/
/ \\ / \\ \\ 00 /
/ 01 \\/ 11 \\ \\ /
/--------------\\ \\/
/\\ /\\ /\\ /\\ /\\
/ \\ / \\ / \\ / \\ / \\
/ 00 \\/ 01 \\/ 02 \\/ 03 \\/ 04 \\
-----------------------------------
\\ 05 /\\ 06 /\\ 07 /\\ 08 /\\ 09 /\\
\\ / \\ / \\ / \\ / \\ / \\
\\/ 10 \\/ 11 \\/ 12 \\/ 13 \\/ 14 \\
------------------------------------
\\ 15 /\\ 16 /\\ 17 /\\ 18 /\\ 19 /
\\ / \\ / \\ / \\ / \\ /
\\/ \\/ \\/ \\/ \\/
See https://gist.github.com/shanewholloway/8987507c06583ff5a5f33012fa10ab9d for an improved version.
Complete icosahedral 3D lib to come...