Performance capture systems are used to acquire high-quality animated 3D
surfaces, usually in form of a dense 3D triangle mesh. Extracting a more
compact, yet faithful representation is often desirable, but existing solutions
for animated sequences are surface-based, which leads to a limited approximation
power in the case of extreme simplification. We introduce animated
sphere-meshes, which are meshes indexing a set of animated spheres. Our
solution is the first to output an animated volumetric structure to approximate
animated 3D surfaces and optimizes for the sphere approximation,
connectivity, and temporal coherence. As a result, our algorithm produces
a multi-resolution structure from which a level of simplification can be selected
in real-time, preserving a faithful approximation of the input, even at
the coarsest levels. We demonstrate the use of animated sphere-meshes for
low-cost approximate collision detection. Additionally, we propose a skinning
decomposition, which automatically rigs the input mesh to the chosen
level of detail. The resulting set of weights are smooth, compress the animation,
and enable easy edits.