 
Summary: Spacetime Surface Reconstruction Using Incompressible Flow
Andrei Sharf Dan A. Alcantara
University of California at Davis
Thomas Lewiner
PUCRio de Janeiro
Chen Greif Alla Sheffer
University of British Columbia
Nina Amenta
University of California at Davis
Daniel CohenOr
Tel Aviv University
Figure 1: Reconstruction of a spacetime surface. Left: A sequence of point clouds of a running man containing holes due to self occlusions.
Middle: Renderings of two iterations of our flow solver. Cells confidently identified as being inside the surface are colored dark blue. As the
solver progresses, mass accumulates inside the surface. Right: The result of an implicit function reconstruction from the flow solution.
Abstract
We introduce a volumetric spacetime technique for the reconstruc
tion of moving and deforming objects from point data. The output
of our method is a fourdimensional spacetime solid, made up of
spatial slices, each of which is a threedimensional solid bounded
by a watertight manifold. The motion of the object is described
