Abstract
This article proposes a sketch-based interface for modeling muscle fiber orientation of a 3D virtual heart model. Our target was electrophysiological simulation of the heart and fiber orientation is one of the key elements to obtaining reliable simulation results. We designed the interface and algorithm based on the observation that fiber orientation is always parallel to the surface of the heart. The user specifies the fiber orientation by drawing a freeform stroke on the object surface. The system first builds a vector field on the surface by applying Laplacian smoothing to the mesh vertices and then builds a volumetric vector field by applying Laplacian smoothing to the voxels. We demonstrate the usefulness of the proposed method through a user study with a cardiologist.