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Today we would like to show you how to create Meshes from your building walls using your laser scanner point clouds. Here you find this posts example laser scannin data.

We start with a simple wall which you can see in the following scan (scan facade 15).

So sieht die Wand in der Panorama Ansicht in PointCab aus.

This is what a wall looks like in a panoramic view in PointCab.

After importing your point cloud data you will see the automatically generated standard views. First of we adjust our project settings. Therefor you go to Data –> Settings and activate the Mesh tab and set the Mesh accuracy to 0,001m aka 1cm and the median filter to none. Then press ok.

Passen Sie die Mesh Einstellungen an.

Adjust the mesh settings

Now we define a section in the top view:

  1. Define the section a bit larger than what the wall is. The exact area for the mesh will be defined later.
  2. Position the Section line (red dotted line) exactly on the wall line.
  3. Define a small clipping box area(yellow area). In our example it is 3cm in front and after the section line.
  4. For a detailed reproduction use a 5mm resolution.
Die richtigen Schnitt Einstellungen für die spätere Vermaschung

The right settings for an exact mesh

Open up the front view and adjust the section hight. Again we adjust the clipping box to be a bit over the the seiling and floor.

Passen Sie Ihre Schnitt Definition in der Front-Ansicht an.

Adjust the section settings in the front view

Start processing the section job and open the results by right clicking the section job and choosing open.

Machen Sie einen rechten Mausklick auf den Schnitt-Auftrag und klicken auf öffnen

Open a PointCab Job.

Now you see the section orthophoto. Details, like the wall plugs and the window reflections, can be clearly identified. We start defining our mesh. By pressing and holding the SHIFT button we can create axis-parallel lines.

Die Orthofoto Fläche für die Mesh Erstellung

Activate the Mesh tool and define the Mesh lines exactly on the outer wall corners. To be better able to understand the settings afterwards you should now set the mesh accuracy to 5mm and the filter to 0cm and start processing the mesh.

Versuchen Sie es erst mit detaillierten Einstellungen

Aftzer the processing is done you can see the many mesh points displayed in your section orthophoto. Open up the 3D view of the Mesh result by clicking on it with a right click again and choosing open.

Öffnen Sie das Mesh im 3D View.

Open the 3D view. 

Machen Sie einen rechten Mausklick und gehen auf Editieren

You now see that there are some distraction points in your results. You can now simply edit and adjust the detail settings of your Mesh Job to get a more harmonized result in the end:

  • Mesh accuracy 1cm – means that only points sticking out more than 1cm create a new mesh point
  • Filter Objects 5cm – All distractions with a samller footprint than 5cm x 5cm will be filtered.

Every time you edit a previously processed job the data will be lost buit the settings will be kept. This way your result folders stay lean even hough you keep creating new results.

Das Mesh aus Ihrer Punktwolke

You find all your 3D results in the folder Project_Results3D.

Next to the formats DXF and DAe we have only created a DWG file for this example. The file has a size of 65kband can be easily used in any CAD system. You can download the example file here.

Here you see the file loaded up in Autodesk DWG TrueView.

DWG in DWG TrueView

You can find further tutorials under: https://www.pointcab-software.com/en/support/tutorials/