Cubes files format:
N-by-8 matrix, where N is the number of cubes
Each row contains the x,y values of the four vertices comprising a single cube arranged in x1,y,1,...,x4,y4 form.

trajectory files format:
M-By-2 Matrix, where M is the number of time steps.
Each row Each row contains the x,y values of the trajectory in the ith time step.
