Finally understood how to generalize the diamond tiling algorithm from 1D+1T spacetime to 2D+1T spacetime for stencil code. This mysterious diagram now makes perfect sense. But to the researchers at Keldysh Institute of Applied Mathematics, this algorithm was already obsolete for 20 years. It was already in used in Russian HPC code of the late 1990s and was known as "ConeTur". In the mean time, they invented 3 generations of newer algorithms, which are even more incomprehensible. Keldysh is at least 10 years ahead of the rest of the world... #hpc