DG Kernel Forum

Hi,

This may not be the most appropriate forum topic as it's more philosophical than DGKC specific, but I was wondering about the general techniques for building geometry from a point cloud, especially if you would like to modify the resulting surface. I know DGKC has built in functionality to do this with mesh (although I haven't tried it yet). However, I was wondering if is it practical to build a BRep surface from a point cloud, and what the pros and cons might be? I also wanted to be able to modify various properties like width and height on generation, so I'm trying to consider my design choices carefully. To summarise my question, what are the typical approaches to building geometry defined by a point cloud + additional parameters? Any thoughts/advice would be greatly appreciated.

Thanks in advance!

Hi RJD
It is a good question.

We have point cloud to mesh conversion (Cloud sample), which is relatively easy. So, mesh is nearly same thing as point cloud. So, I recommend focusing on mesh instead. You will find more options this way.

Point cloud or mesh to BRep conversion generally is not possible automatically. This is because point cloud is a nearly completely raw unprocessed data. Parametric formats have lots of structure and logic inside.

There are expensive tools which claim can do the conversion. One was called Re-Shaper. Not sure. It was a while. I personally have not tried any. I believe they are rarely automatic and need human assistance. They might be good if you do this frequently.

There are few cases when the conversion is possible. One is when the input is just the result of digitizing of a single surface patch. Our Diff Surface sample demoes a way to fit a BRep face into the mesh obtained from the cloud. This can be generalized, but the main issue there is separating input into smooth patches, which can be difficult.

Another one (only a little different) is the case when you know the structure of the input. So, you can construct the result and adjust the dimensions using the input. It needs a bit of coding.

The most practical one in my view is to redesign the part in a traditional CAD software with taking measurements from the input. The result can be compared in 3D. I bet there are some tools to assist with that also. You can also find freelances or specialized services to do the job.

See also: Mesh vs parametric.

Regards