Metaballs-Based Real-Time Elastic Object Simulation via Projective Dynamics

In this paper we present a novel approach for real-time elastic object simulation. In our framework, an elastic object is represented by a hybrid model that couples metaballs which are distributed adaptively and a triangular surface mesh. We use the centers of metaballs as physical particles and apply Projective Dynamics for deformation simulation. To produce more realistic simulation, we propose a new Projective Dynamics constraint for metaballs that governs the elastic behavior using the deformation gradient approximation for each metaball. The metaballs generated by the self-adaptive method can better maintain the geometric feature details of the model, which enhance the model resolution in surface area. Furthermore, we propose a GPU based surface skinning method for the coupling of the triangular mesh and the metaballs. Our skinning method integrates the skinning process into the rendering pipeline and enables fast skinning of large-scale surface meshes. The experimental results show that the proposed method can obtain more plausible visual effect while achieving real-time deformation of 3D models.