Did some exploration of the parameter space of the packing algorithm for comparison of the C++ a Julia versions. Moved values of one parameter and fixed all others to the same values. 10 iterations for every parameter were done and collected densities of resulting packing configurations of 8 tetrahedra. The initial configuration of tetrahedra were same in all cases.
The initial density was 0.06415. The best I got from the experiments was 0.67045. Below are the visualizations of the packings.
Left initial packing of 8 tetrahedra in a unit cell and right best packing achieved.
Left 27 unit cell of the initial packing. Right 27 unit cells of the best achieved packing.
