Polyline cornes

[jgruber]

HI everyone!
I have a big laserscan point cloud with millions of points. My CAD programm isn´t able to handle such a big mass of ponts, so i am trying to reduce them with cloudcompare.

So i imported my points and also a dxf with polylines wich are the axes of the roads i am planing in this area. I used the "extract points along active sections" feature and cut out a corridor of 30 m. Now my CAD application createt the terrain model without any problems - great!

But then i saw that in the corners of the polylines the points are missing (added a screenshot).

How can i handle this problem?

Kind regards
Jakob

[daniel]

Well, points are indeed extracted up to a given distance to the polyline, but this distance is the orthogonal distance to the segment. Therefore, if two consecutive segments are not parallel, and are diverging quite far one from the other, then some points will be missing.

And to avoid this... apart from increasing the maximum distance to the polyline, I don't know! Another solution would be of course to increase a lot the number of polylines, especially in the areas with a high curvature.

[matknaak]

Hi Jakob,

maybe I did not fully understand your problem, thus, this might be a silly suggestion, but why don't you use cloudcompare to do the terrain model (using "Rasterize" tool), export the dtm as a raster and clip the raster in your CAD. This might be easier and most likely faster too.

cheers

mat