How to calculate the back fill volume in point cloud ?

^{Originally posted by **Lyhour-Chhay** December 13, 2021}
I appreciate your much effort for conducting this work. I want to calculate the back fill volume into the hole of point cloud. I will show you in the picture. I have been constructed the 3D point cloud of pavement texture as show in the figure 1. I want to find how much volume should fill into the point cloud to make smooth surface. My objective is want to calculate the mean texture depth (MTD) as show in the figure 2. Conceptually (figure 2 and figure 3), we have the sand with the known volume then we spread on the surface. After that, we determine the area of spreading. Then we can obtain the MTD: sand volume / area of spreading. I can find the area of point cloud. but I don't know the volume corresponding to the peak height of point cloud as in the conceptually description. Therefore, it would be better if you could guide me or show me h ow to do it. I am sorry for bad English I hope you understand. Thank you very much sir.
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