SuGaR: Surface-Aligned Gaussian Splatting for Efficient 3D Mesh
  Reconstruction and High-Quality Mesh Rendering
Authors: name: Antoine Guédon, name: Vincent Lepetit

We propose a method to allow precise and extremely fast mesh extraction from
3D Gaussian Splatting. Gaussian Splatting has recently become very popular as
it yields realistic rendering while being significantly faster to train than
NeRFs. It is however challenging to extract a mesh from the millions of tiny 3D
gaussians as these gaussians tend to be unorganized after optimization and no
method has been proposed so far. Our first key contribution is a regularization
term that encourages the gaussians to align well with the surface of the scene.
We then introduce a method that exploits this alignment to extract a mesh from
the Gaussians using Poisson reconstruction, which is fast, scalable, and
preserves details, in contrast to the Marching Cubes algorithm usually applied
to extract meshes from Neural SDFs. Finally, we introduce an optional
refinement strategy that binds gaussians to the surface of the mesh, and
jointly optimizes these Gaussians and the mesh through Gaussian splatting
rendering. This enables easy editing, sculpting, rigging, animating,
compositing and relighting of the Gaussians using traditional softwares by
manipulating the mesh instead of the gaussians themselves. Retrieving such an
editable mesh for realistic rendering is done within minutes with our method,
compared to hours with the state-of-the-art methods on neural SDFs, while
providing a better rendering quality.