Extract shape parameters from TopoDS_Solid or TopoDS_Shape?

Severin Pappadeux
Sat, 06/10/2017 - 02:52

Forums:

Hi, All

Got on my hands STEP file, which I was able to read and retrieve TopoDS_Shape(TopoDS_Solid). It looks like small tube bent along complex path.

I'm able to display it, check flags etc, so far so good. But how I could extract actual solid parameters (radii, bending path)?

Any help would be greatly appreciated

Qr Qr
Sat, 06/10/2017 - 07:42

All features, such as bends, whatever, are lost once the model is saved to STEP (or any other neutral) format. Generally speaking, what you need is automatic feature recognition. In a simple setting, you can just traverse through the faces of your model and check the host surface types. A cylindrical surface may mean bend. Its radius will be the radius you're looking for. Can you share your file to have better idea on kind of features it contains?

Severin Pappadeux
Sat, 06/10/2017 - 15:21

thank you for the reply.

Yes, I have several faces etc inside the solid, but they all are of TopoDS_Face type, so question how to get data from that is still open.

Please find attached STEP file

Attachments:

curve.STEP

Qr Qr
Sat, 06/10/2017 - 19:01

I will have a look, thanks. In the meanwhile, you can refer to BRep_Tool::Surface() method which gives access to the host geometry of your topological faces.

Severin Pappadeux
Sun, 06/11/2017 - 05:28

Thank you , will try

Just in case I've attached Python code I used to read and display it - works for me on Anaconda2, python-2.7, python OCC binding

regards

Attachments:

import_curve.py.txt

Guido van Hilst...
Sun, 06/11/2017 - 11:49

Hi Severin

I have made a small script that shows your step-data,

and loops over the edges.: ExtractShape

In the log file you can see all curve types.

Best regards, Guido

Severin Pappadeux
Sun, 06/11/2017 - 20:41

Thank you, Guido

looks like what I needed

sincerely