Step file exported with incomplete coordinates

Rhino
,
1

Hello,

I have exported a surface geometry to a step file, but there are some coordinate components missing. Is it supposed to be like that?

I have chosen the STEP Scheme: ‘AP203ConfigControlDesign’, with the option ‘export parametric space curve’ selected. as I need to have the information ‘B_SPLINE_SURFACE_WITH_KNOTS’.

Thank you.

Bild1
Bild11192×720 235 KB

test_file.stp (21.0 KB)
test_file.3dm (36.3 KB)

3

Hi 최명진

I believe so, when importing back into Rhino it appears OK.

I did assign this a developer who might have additional insights.

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4

The points with 2 coordinates are 2d points, associated with trim (2d) curves. You can work backwards through the id numbers. Start with your example

#319=CARTESIAN_POINT(‘’,(0.,0.));

Search for #319 and you’ll find

#144=B_SPLINE_CURVE_WITH_KNOTS(‘’,1,(#318,#319),.UNSPECIFIED.,.F.,.F.,(2,
2),(-1.975,0.),.UNSPECIFIED.);

Search for #144 and you’ll find

#80=DEFINITIONAL_REPRESENTATION(‘’,(#144),#417);

Search for #80 and you’ll find

#60=PCURVE(‘’,#197,#80);

Search for #60 and you’ll find

#100=SURFACE_CURVE(‘’,#143,(#60),.PCURVE_S1.);

The last object is the trim curve. You can keep working backwards and the further you go the higher up in the brep topology you get.

I hope this helps.

Cheers,
Tim

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