“…In early works, 3D volumes [13,17,58] and point clouds [46,16,45,1] are adopted as the outputs of the networks, which suffer from the problems of losing surface details or limited resolutions. With the development of the graph convolution network, many recent methods [18,23,57,27] take the triangle mesh as the output representation, most of which regress the vertices and faces directly and require initial template and fixed topology. Most recently, there has been significant work [33,40,22,12,15,8] on learning an implicit field function for surface representations, which allow more flexible output topology and network architectures.…”