Add surface splatting in polyscope?

Hi,

Just played a little polyscope with point cloud data. To get a good matcaps result for point cloud like here, it seems that quite much points (might be millions points) are needed, otherwise the surface looks quite "ball making".

How about to add surface splatting in polyscope to solve this "ball made surface effect"? It looks that Potree use both matscaps and splatting, because after zooming under the surface the "ball" can be seen, but the surface looks quite smooth.

该 issue 提议在 Polyscope 的点云渲染中加入 surface splatting，并链接到 surface_splatting 项目，但没有列出源文件、测试或入口点。首先检查链接的项目，并定位 Polyscope 的点云渲染路径；完成标准是确定一份达成共识的设计，并验证球状表面效果已得到减弱。