Upon receiving several requests for my space-time densities code I have decided to make it open. It is freely available here:
Note that the code is for Matlab/Octave and it produces a density volume, for which you will need some kind of volumetric visualisation system to be able to see the results.
This is the code developed in the following paper:
Demšar U, Buchin K, van Loon EE and Shamoun-Baranes J, 2014, Stacked space-time densities: a geovisualisation approach to explore dynamics of space use over time. GeoInformatica, Advanced Online Publication, DOI 10.1007/s10707-014-0207-5