Localized Verlet Integration Framework for Facial Models

Traditional Verlet integration frameworks have been successful with their robustness and efficiency to simulate deformable bodies ranging from simple cloth to geometrically complex solids. However, the existing frameworks deform the models as a whole. We present a Verlet integration framework which provides local surface deformation on the selected area of the mesh without giving any global deformation impact to the whole model. The framework is specifically designed for facial surfaces of the cartoon characters in computer animation. Our framework provides an interactive selection of the deformation influence area by using geodesic distance computation based on heat kernel. Additionally, the framework exploits the geometric constraints for stretching, shearing and bending to handle the environmental interactions such as collision. The proposed framework is robust and easy to implement since it is based on highly accurate geodesic distance computation and solving the projected geometric constraints. We demonstrate the benefits of our framework with the results obtained from various facial models to present its potential in terms of practicability and effectiveness.