view_inds = knn(grasp_views_trans_, grasp_views_, k=1).squeeze() - 1
grasp_views_trans = torch.index_select(grasp_views_trans, 0, view_inds) #(V, 3)
grasp_views_trans = grasp_views_trans.unsqueeze(0).expand(num_grasp_points, -1, -1) #(Np, V, 3)
grasp_views_rot_trans = torch.index_select(grasp_views_rot_trans, 0, view_inds) #(V, 3, 3)
grasp_views_rot_trans = grasp_views_rot_trans.unsqueeze(0).expand(num_grasp_points, -1, -1, -1) #(Np, V, 3, 3)
grasp_labels = torch.index_select(grasp_labels, 1, view_inds) #(Np, V, A, D)
grasp_views_trans = torch.index_select(grasp_views_trans, 0, view_inds) #(V, 3) 像是对齐到物体坐标系，
grasp_labels = torch.index_select(grasp_labels, 1, view_inds) #(Np, V, A, D) ，最初 grasp_labels在物体坐标系，怎么对其到相机坐标系
是不是应该反过来 view_inds = knn(grasp_views_, grasp_views_trans_, k=1).squeeze() - 1
