Full Version: composite curve export to STEP

Saving composite_curve.3dm as composite_curve.stp results in a spline rather than a composite curve of lines and arcs. I expect a composite curve because WriteAnalyticCurves=y is set in moi.ini

This is preventing me from round-tripping through other software via STEP because MoI can't easily edit its own STEP output.

Is there a way to export joined curves as composite curves when saving to STEP?

- Peer

Attachments:
composite_curve.3dm
composite_curve.stp

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It appears to be a STP translation setting as "Desired"

Alot of the MCAD stuff that uses parametrics have settings to refrain and maintain the "Separated" curves.

You can see this with your Simple example file by deleting the added points (Show points and select the 4 center points only, then delete them)

Your original composite curve returns!

The other option could be to give it a unique name or style and separate it for export. Rejoin it when needed.

Maybe Michael has a deeper setting to manage it.

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Hi Peer, currently MoI can read composite curves from STEP but there isn't any way to write them.

It is supported by HWLibs though so I will set it up to do that.

I've attached the result from exporting your file, does that work?

- MIchael

Attachments:
composite_curve2.stp

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Michael: Thanks for working on this! Yes, composite_curve2.stp is what I need.

BurrMan: I don't understand what you mean about deleting edit points. I see 16 edit points in composite_curve.stp and deleting any of them distorts the curve when I try that. Are you saying Trim followed by deleting the mid-span points?

- Peer

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Hi Michael,

The new composite curve writer will work on arbitrary curves and not just analytic types, right? For example, a joined line-helix-arc will be output as a composite LINE-BSPLINE-CIRCLE?

- Peer

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Hi Peer,
I was a little off. I had just done a simple test at first and replied. THe3 video shows what I did.

Then after you responded, I dove a little deeper and discovered it was just an anomaly that wouldn't really work. I believe the end of the video shows what you experienced.



Anyway, it sounds like Michael understands and is going to be able to help you...

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HI Peer,

> re:
> For example, a joined line-helix-arc will be output as a composite LINE-BSPLINE-CIRCLE?

I think so, attached is an example of a joined line-helix-arc.

- Michael

Attachments:
composite_curve3.stp

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Michael: Thanks for confirming. That's perfect.

BurrMan: Thanks for posting a video of what you did. That's an unexpected quirk you discovered there.

- Peer

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Yeah. It was odd in that it was the ONLY way it produced results. Virtually every other way gets messy results!

Just my luck....

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