Simplifying process to extract section view from point cloud

[Anonymous]

Firstly, thank you very much for spending your time to read this.

The issue I'm encountering is about drawing a 2d section view from a point cloud.

I'm currently using AutoCAD 2016. After attaching Point Cloud, I have been trying to extract 2d sectional view. As it can be seen from the photos, the mesh is not the smoothest (based from photogrammetry), and I need a clean 2d section drawing.

One method I did was tracing manually and plugging onto the 2d drawing so I could produce a drawing.

It was possible since the shape was rather simple. However, I need a more automated and simpler process since this will take too much time to perform on future instances. The green lines on the photo are section lines derived from multiple section views which I used after creating a section view. If you know a method to produce 2d drawings from a point cloud or anyone who can produce it from 2d drawing, that would be very very helpful.

I have attached some screenshots and the file that I've been working on, so if you'd like to have a look, it would be much appreciated.

Thank you for your time for reading this.

[Alfred.NESWADBA]

Hi,

>> After attaching Point Cloud, I have been trying to extract 2d sectional view.

>> As it can be seen from the photos, the mesh is not the smoothest

I'm not sure about the wording here ... if you have a point-cloud, you would not have a mesh!

When you really have a point-cloud attached to your drawing then try to use the section-plane tool for the point-cloud and then run command _PCEXTRACTSECTION (>>>details<<<).

- alfred -

[Anonymous]

The point cloud I have is the vertices of a mesh I have and this mesh has pretty rough surfaces. I have made section and made section lines but they dont gove me good results. I wish to make an engineering drawing and just with section line I can't make the drawing I want...

[Alfred.NESWADBA · Accepted solution]

Hi,

>> The point cloud I have is the vertices of a mesh I have and this mesh has pretty rough surfaces

I don't see any mesh in the data, also the reference points to a RCP-file which is a ReCap project file (which we don't see, but most probably are points).

The filename of the RCP file has a name including the words "decimation" and "simplified" ... can you get access to the original file which might have a higher resolution?

>> I wish to make an engineering drawing

Therefor you can use sections in a similar way as a sketch. It's nothing else than a background for your construction, but you need to draw your objects on your layers, using ortho-mode, using correct values (when you have them they are better than object-snap to a point-cloud), you should use your block-definitions/symbols like screws, and so on. That makes a drawing structured and useful, a section-object never can be such a result (nowadays).

- alfred -

[Anonymous]

Thank you very much for your help. simplification and stuff means that the unnecessary scene. 

I have attached the point cloud files if you're interested to look.

I have made a drawing with a point cloud with more points. I had to manually draw them in the end, however with more points the drawing was more accurate.

The method I chose was making multiple segments lines by moving the section plane across the point cloud and drawing section line each time after movement. It has resulted in sketches which could be traced later on.

I have attached the finished drawing.

Thank you very much for help.

[john.vellek]

Hi @Anonymous

Did you try the _PCEXTRACTSECTION that @Alfred.NESWADBA suggested? It should save you a lot of effort in creating your views.

[Anonymous]

It is done and dusted, still thank you for the reply.

I basically drew multiple section lines at different thickness, paste to paperspace to flatten section lines located at different heights, then traced the drawing manually.

Hope this post helps others in need as well.