Polylines across point cloud

[LeakHeat]

Hi all,

Loving the program, very new user to it and seem to find out more things about as I go along. But do have a few problems I'd like some help with please?

So, I have a point cloud export from Agisoft, very detail (22million points) in diffrent file formats. Currently I have a .pts file open in CC.

On the screen is the point cloud and the scaler field of my model. The model has intential pot holes, buldges and cuts in it. What I want to do, is draw a polyline across one of the pot holes and contor the hole. Firstly in the X_Y plane then the X-Z plane, making me a polyline image which I can then export the contor lines to CAD and produce a drawing from them.

I have got as far as adding the polyline X-Y, X-Z but everytime I do it i get stuck. The lines are always long and dont stop just at the edges of the pot hole they go all the way round the model and backagain. This I have been tearing my hair out about. Havn't got to the point to export anything yet.

Please see a few screen grabs of what I trying to explain.

Polyline across pot hole_5.jpg (47.08 KiB) Viewed 5053 times

Polyline across pot hole_1.jpg (43.39 KiB) Viewed 5053 times

At the end of the day, I need to take all these imperfections and produce drawings for them all. Is it possible the whay I am doing it? Or is there an easier way?

Many thanks for any comments on the above.

Chris.

[daniel]

Do you have points 'below' the hole? I guess CC consider that some points quite far away from your holes as being part of the 'section'.

You should try to segment out the hole first. Use the scissors tool (http://www.cloudcompare.org/doc/wiki/in ... ation_Tool) to isolate the area you want to extract the contour from. I guess things should go easier then.

And this way you could use the the automatic contour extraction feature in the 'cross section' tool.

[LeakHeat]

Hi Daniel,

Thanks for such a quick reply. What you suggest is quite interesting. I could "snip" out each bit i need of the model as there own little clouds and then section them up for export to CAD. I shall give it a try. Also found this .pdf, http://www.cloudcompare.org/doc/qCC/Clo ... ool_V2.pdf this is the tool you mean isint it?

Many thanks again. Once I have had a tinker will let you know how I get on.

Kind regards,

Chris.

[daniel]

Indeed!

But I can't remember right now if this tool lets you extract partial contour (upper/lower) or only full ones... In which case you'll have to stick with the 'section extraction' tool.

[LeakHeat]

Evening Daniel,

Just doing a promised follow up. For a few reasons it din't quite work out but I tried a few things and now have what I think I want. I snipped the areas out of a sectioned piece of the point cloud. Then used those small snipped sections it with the poly line tool and created small steps (0.001m) on the upper suface only.

2016-02-29_16-49-05.jpg (2.94 KiB) Viewed 5030 times

2016-02-29_16-36-22.jpg (3.27 KiB) Viewed 5030 times

But now, I've tried a number of cad packages, and they cant load the poly line sections or deal with them in .dxf. Even PTC Creo is having issues. Is there any way to export the vector 2D measurement lines as actual dimentions? Or have you any other ideas?

Kind regards,

Chris.

[daniel]

I know that Autocad only supports 2D polylines (therefore you have to transform the polylines first so as to get them aligned with the XY plane). Not sure about the other software tools. What kind of errors did you get?

The only other choice to export polylines is to use the SHP format. But this is definitely not a CAD format (more a GIS one).