How to remove hidden points from point cloud using normal vectors (in matlab)?

Question

I have text file with point cloud data. This document contains six columns: x,y,z coordinates of points and nx,ny, nz - normal vector coordinate i.e.,

-2.27535 2.33442 12.8694 0.492013 -0.866115 -0.0881364 

Could anyone tell me how can I remove hidden points (which are located in the back surface or are not visible in the view) using normal vector? I'm using Matlab.I will appreciate every helpful tip.

Answer 1

You probably refer to back face culling: you can determine, using dot product between the normal vector and the view direction whether the normal faces the viewer (negative dot-product) or faces away from the viewer (positive dot product).