Halvorsen attractor

Animation of Halvorsen attractor.
dx/dt = -a * x - 4 * y - 4 * z - y * y
dy/dt = -a * y - 4 * z - 4 * x - z * z
dz/dt = -a * z - 4 * x - 4 * y - x * x
a = 1.4, dt = 0.001
starting point = ( -3.059, -4.877, -0.003 )
Rotation over Y axis.
80 million points.
UHD 4K 3840x2160 60 fps.
Generation of 18 seconds video (1080 frames) took 7 hour 41 min.