1. A three-dimensional reconstruction process comprising: identifying a fuzzy object in a two-dimensional image; selecting a particle system from a plurality of predetermined particle systems, the selected particle system relating to a predefined fuzzy object; simulating the selected particle system; rendering the simulated particle system; comparing the rendered particle system to the identified fuzzy object in the two-dimensional image; and wherein if the comparison result is less than a predetermined threshold, accepting the selected particle system to represent a geometry of the identified fuzzy object.