About the 3D point cloud supervision in loss function

[yangqinhui0423]

Hello authors! Thanks for your excellent and interesting work.
I am confused about the 3D point cloud supervision in loss function.
Where is the ground truth 3D point cloud come from?
And is the point cloud loss between ground truth point cloud and the Gaussians?

[zouzx]

The GT 3D point cloud is generated from the rendered depth images. And yes, the point cloud loss compares the GT point cloud with the positions of the Gaussians.

[yjb6]

I'm a bit confused here. Why can't we sample the GT point cloud from the 3D mesh, but instead have to generate it from the depth map? Thanks for the answer.
@yangqinhui0423 @zouzx