Working with point clouds

[jak79]

I am looking for what programs are required to import scan point clouds & convert to a surface for use with C3D 2012.

Our use of the scanner is mainly civil projects (parking lots, roads etc.) I don't really need to model objects but do need line work (curb lines, sidewalk lines) also to us as a backdrop in out plans. Information how to create these two items (tin surface & line work) is my main goal.

Any help or current practices is appreciated.

Thanks

[Alfred.NESWADBA]

Hi,

>> [...] what programs are required to import scan point clouds & convert to a surface for use with C3D 2012

Short answer: Civil3D2012 😉

Or missed I something?

Create a new point-cloud in your Civil ... and after that you can right-click the point-cloud and convert it (or parts of it) to a surface.

- alfred -

[d_reno]

depending on the density of points you may want to weed them out (in the surface properties I think) cause point clouds are a great way to get plenty of break time as you wait for your machine to process the data. I use LIDAR data consisting of a couple million points to create surfaces and it makes me wish for a Cray. it is not practicle, IMO, to use point clouds for design surfaces because of the huge lag times in virtually everything you do with that surface.

if contours alone will do for your display, try using Map tools to create a surface. it is only a picture of the data - the contours - but it doesn't require nearly as much machine resources to produce. presumably you'd have to go over everything to draw in the features, like curb lines, you want to see. I think you would have to do this even when creating a surface in C3D - it won't automatically create lines at logical breaks (like a curb back) for you, as far as I know.

[mathewkol]

You may be doing this already but...there are 2 very important things you need to do before working with a cloud.
1. Get ground points. The scan will have points on trees, hyrdrants, wires etc. These must be removed to have any usable points for your TIN.
2. Decimate (weed) the data. Typical clouds are many millions of points. Except when yourr working on a large project, this is far too many. They could be millimetres apart in some areas.

How do you go about this? You don't (unless you're the one doing the scanning). No, you define the terms for you cloud provider. They shouyld have and use software that does both of these things.

Specify that you need the points every 1 metre or so. That's plenty EXCEPT around grade breaks. You need more here. This is called intelligent decimation. Remove a whack of points except where I need them most 20 million points is too much data for a surface. It can be done but it's gonna be slow.

I don't know of any software that will draw lines for you. There was an application on Autodesk labs that did a bit of that but I think it's down now.

[Neilw_05]

This thread explains how to decimate point clouds but I have not been able to get the results that Autodesk claims.

http://forums.autodesk.com/t5/AutoCAD-Civil-3D/Clip-or-filter-point-cloud/m-p/3144490/highlight/true...

As for linework, there isn't any way to generate lines from clouds that I am aware of. The density of points should negate the need for breaklines but we still need lines for planimetrics. You may have to get them from a ground survey or trace from a photo, etc.

[vick1z]

Hi Everyone,

sorry to jump in this but I'm also facing some issues. How Can I bring point cloud in civil 3d ?

I can see any tab on prospector tab to bring point cloud in.

Please assist in this

[TerryDotson]

If you're using Civil3D 2015 or higher you can grab this freeware to take Lidar straight to a TinSurface.

[FDGJames]

Not certain of your version but on 2018, under the Insert Ribbon,  there lives a point cloud section.  Assuming you have ReCap files, it will let you attach them here.  In previous version 15, 17? I could create a surface from a point cloud right in C3D, but I believe that has been removed in the last few versions.