Working with Point Clouds

[Shea_G]

I mainly work with point clouds from UAV surveys for my surfaces. I decimate them to about 5 million points before I bring them into civil. Even at that as soon as I start to design off them and manipulate them my drawing gets slowed way down to an unusable point soon or later. Anyone have any tips with working with point clouds?

[rl_jackson]

Are you using data shortcuts for the surface file?

Whats your import format? RCP, LAZ etc.....

[samir_rezk]

Hi,

I have experimented with simplifying the surface to a more reasonable total no. of points to be comparable to a ground survey depending of course to the terrain your working with. what seems to help a little more is if you create a land xml file from the point cloud surface and then recreate the surface in a new drawing from the land xml file instead. 

Hope this helps,

[Anonymous]

My workflow is to subsample the point-cloud in CloudCompare to a 0.5m or 1m point distance. Then create in C3D a surface from that pointcloud. After that you can extract contour lines from that surface, and add that 3D-polylines to a different surface. Before you extract that contour lines you must set a range interval.  But it depends of the accurancy that you want for your surface..

When you want the best surface you must triangulate the original pointcloud. But that slow's down C3D..

[Anonymous]

I've been working with very large point clouds lately and this is how ive been getting them to run better.

-create surface from point cloud (using a distance between points 1-5)

-exporting the surface as a dem with elevation sampling on a 2m grid

-create new surface and add the dem

-then using data shortcuts

[Shea_G]

I started using data shortcuts and that helped quite a bit, thanks for the tip.

As for the recommendations to convert my surface into different formats and bring it back it at a lower resolution, is there any benefit to that versus subsampling my point cloud in CloudCompare more then I already do (0.5m)? Does a DEM or XML process better then a .las built surface or is it just that those surfaces now have less nodes/triangles?