  We present an algorithm that allows a user within a virtual environment to
perform real-time unconstrained cuts or consecutive tears, i.e., progressive,
continuous fractures on a deformable rigged and soft-body mesh model in
high-performance 10ms. In order to recreate realistic results for different
physically-principled materials such as sponges, hard or soft tissues, we
incorporate a novel soft-body deformation, via a particle system layered on-top
of a linear-blend skinning model. Our framework allows the simulation of
realistic, surgical-grade cuts and continuous tears, especially valuable in the
context of medical VR training. In order to achieve high performance in VR, our
algorithms are based on Euclidean geometric predicates on the rigged mesh,
without requiring any specific model pre-processing. The contribution of this
work lies on the fact that current frameworks supporting similar kinds of model
tearing, either do not operate in high-performance real-time or only apply to
predefined tears. The framework presented allows the user to freely cut or tear
a 3D mesh model in a consecutive way, under 10ms, while preserving its
soft-body behaviour and/or allowing further animation.
