Comment by sergmiser
3 hours ago
Not substantially faster as your still drawing roughly the same number of primitives (Gaussians are rendered as a quad covering the splat area), and the extra cost in shading isn't that expensive compared to all the fragment samples / depth tests. Triangles also tend to be less effective at modelling most real world 3D scenes. In most cases I tried, it required more primitives, longer training, and ultimately lower FPS and PSNR than 3DGS. Other methods like PSGR also helped push 3DGS to better fit real world geometry. Triangle splatting and its variants do not generate clean efficient meshes like what you might be used to with a modelled scene [0].
They address the lower PSNR for triangles compared with gaussians in the paper, basically PSNR rewards smoothness more than visual quality and gaussians are very smooth. I hadn't seen PSGR[0] before, that looks pretty good but it looks like it's pretty close to the triangle splatting. They flatten the gaussians to flat primitives with varying opacity like the triangles, but the authors of triangle splatting specifically call out that their window function is bounded by the triangles edges which produces better details in some areas. It kind of proves my point about 3DGS getting a lot of research and incremental improvement though, while I haven't seen any follow up research on triangle splatting. They do mention that their method would need additional steps in order to produce a connected mesh, but I think at least in their example images the surfaces looks pretty decent even thought their still made up of a triangle soup.
I just checked if they had released any follow up papers themselves, and one of the lead authors has published a paper about sparse geometry[1] that looks interesting. He's also done a couple of direct follow ups to triangle splatting called Triangle Splatting+[2] and Mesh splatting[3], that produces a connected mesh. It's at least good to see that there's still research into other techniques than just gaussians.
[0] https://zju3dv.github.io/pgsr/
[1] https://lessvrong.com/cs/nexels/
[2] https://trianglesplatting2.github.io/trianglesplatting2/
[3] https://meshsplatting.github.io/