Symbol Distance Field Calculation For Arbitrary Triangular Surface Models

Recently using distance fields to represent the graphic objects have been widely used in the field of computer graphics. Thus it is especially important to compute the distance from an arbitrary point to the target object. Mostly the distance field is a scale field,which represent the minimum distance from an arbitrary point to the target object?The distance field can be signed in the field of computer graphics, the positive and the negative of the sign denotes the location of the point relative to the object is inside or outside?Many meshes in computer graphics applications are approximate solid objects, but the provided triangular geometry is often unoriented, non-manifold or contains self-intersections actually, all of these will cause inside or outside of objects to be mathematically ill-defined. We describe an efficient algorithm to define and compute a signed distance field for arbitrary triangular models. Thus, starting with arbitrary triangular models, we first define and extract an offset manifold surface using marching cubes with topological guarantees for an unsigned distance field, and remove any interior surface components. Then, we exploit the manifoldness of the offset surface to quickly detect interior distance field grid points. Finally, we implement the S shaped traverse for all grid points to determine the sign of the distance field.We proved that exterior grid points can reuse a shifted original unsigned distance field, whereas for interior cells, we compute the signed field from the offset surface geometry. This will substantially reduce the computation time of signed distance fields. Finally we implemented the algorithm by programming which using C++ and OpenGL, import non-manifold models to experiment and verified the computation of the signed distance field for non-manifold models in this paper is correct and efficient.