Btw, u can ask chatGPT, it will have more intuitive and accurate answers.

Because the points are not like pixels in a continuous space, pointnet first sample a few anchors from the point set. Then every anchor point will find their k nearest neighbor(like CNN works on windows of pixels). Then with shared MLP layers, point will now have higher dimension of latent features. Last, to aggregate features of local points, max-pooling will used on every group of points that we clustered previously.

This is one layer they called Set Abstraction layer. Which repeat for 4 times. After SA layers, Feature Propagation Layers can be used if ur task is segmentation, which just upsampling the points.

3090/ 3090ti Definitely worth the update

Imo 3090 is more than enough for personal use. For dense DL research, one 3090ti card won’t have visible difference than one 3090. Also 3090ti requires much higher total power supply(~1000 vs 3090: ~800).