Eftychios Sifakis, Kevin G. Der, Ron Fedkiw
ACM SIGGRAPH/Eurographics Symposium on Computer Animation (SCA 2007).
We propose a flexible geometric algorithm for placing arbitrary cracks and incisions on tetrahedralized deformable
objects. Although techniques based on remeshing can also accommodate arbitrary fracture patterns,
this flexibility comes at the risk of creating sliver elements leading to models that are inappropriate for subsequent
simulation. Furthermore, interactive applications such as virtual surgery simulation require both a relatively low
resolution mesh for efficient simulation of elastic deformation and highly detailed surface geometry to facilitate accurate
manipulation and cut placement. Thus, we embed a high resolution material boundary mesh into a coarser
tetrahedral mesh using our cutting algorithm as a meshing tool, obtaining meshes that can be efficiently simulated
while preserving surface detail. Our algorithm is similar to the virtual node algorithm in that we avoid sliver
elements and their associated stringent timestep restrictions, but it is significantly more general allowing for the
arbitrary cutting of existing cuts, sub-tetrahedron resolution (e.g. we cut a single tetrahedron into over a thousand
pieces), progressive introduction of cuts while the object is deforming, and moreover the ability to accurately cut
the high resolution embedded mesh.