How to import Dense point cloud from Metashape and generate 2d geometry

[Anonymous]

Hello everybody, I'm new to Autocad and I have a question:

I need for a job to create the contour plan (2d) of an area I flew over with a drone. I generated a 3d model and a dense point cloud on Metashape, and I was wondering the exact step by step procedure to import the dense point cloud to Autocad from Metashape and generate the most accurate contour plan for my customer. Can somebody help me? Thanks a lot.

[maxim_k]

Welcome to Autodesk Forums!

Hi @Anonymous ,

There is no direct way to import Dense point cloud from Metashape.

AutoCAD for Mac cannot attach Point Clouds, but even if you will use AutoCAD for Windows, you will be able to attach Point Clouds only in RCP format (Autodesk ReCap proprietary file format).

Metashape cannot save point Cloud information in RCP format, so you need to convert Metashape Dense point cloud to RCP.

If you cannot use AutoCAD for Windows, you can try to Build Mesh from point cloud data in Metashape and then export this mesh (Model) to DXF format (3D Face) and then open it in AutoCAD.

I use Metashape from time to time for measuring building facades. In this case I export Model from Metashape to OBJ format (with textures), then open OBJ file in Rhino, create orhto projection of facades in Rhino (Capture rendered view to high resolution raster image), then attach this raster image to AutoCAD drawing and trace it using standard AutoCAD objects.

Here you can see a sample of my work:

Model in Metashape:

Model in Rhino ready for exporting to "ortho projection":

[Anonymous]

Hi @maxim_k , thank you very much for your answer. 

If I export the Mesh in DXF format and import it in Autocad, will I be able to generate the 2d geometry of the land (the contour plan) as the customer requested? 

If yes, can you write me a simple list of steps to do so? 

Thank you, have a good day! 

[maxim_k]

>>>>>If I export the Mesh in DXF format and import it in Autocad, will I be able to generate the 2d geometry of the land (the contour plan) as the customer requested?
I'm not sure you will be able to fully automate this process.

Sorry, I cannot say anything concrete without having an exact understanding of the problem that you have to solve and not seeing the initial data in front of me.
Can you describe in more details your task and and show the original data somehow?

[Anonymous]

Yes sure, so basically the customer has sent me the first picture that you see as an example of what he needs from me. 

The land of my aerial survey are terraces but in the majority of the surface those aren't high, the inclination and steepness of the edge is low. I need to produce a highly detailed 2D representation of the land with specific altitude of every terrace like you see in the second zoomed picture. I generated a DEM on Metashape and then the contour plan, as you see in the third picture but Metashape doesn't show the information I need, the altitude of every terrace, that you can find in the north east part of the picture. I'll attach a picture shot by the drone to show you the real world situation. 

[Anonymous]

Here is the picture of the real world situation. As you can see the steepness and altitude of the terraces is low, and I would need to create a detailed representation of each and every "terrace" 

[maxim_k]

I see.

I have never done this kind of work, so I cannot give clear recommendations. However, I can definitely say that it will not be possible to fully automate this process in the AutoCAD.You can try to export model form Metashape in DXF format, but you will get 3D Faces, which need to be converted to a single mesh object in order to create section planes for measuring heights.

I think you can also to look at this Metashape tutorial:

https://agisoft.freshdesk.com/support/solutions/articles/xxx-xxxxxxxx