[SOLVED] STEP file looks differently in FreeCAD vs RealThunder's ASM3 branch

[Pedja]

(Mods, if this is the wrong part of the forum to post this, please move it to appropriate place, thanks.)

Someone(sorry, can't remember the nick) mentioned on IRC an issue with how the particular STEP file looks when imported to FreeCAD.
So I tried it, and indeed, there is a difference in how it looks in vanilla FCAD(0.19-22756 Appimage), and RealThunder's ASM3 daily build(20201019).

Attached are the screenshots showing it, and the STEP file is
https://www.isispace.nl/wp-content/uplo ... e_Open.zip

I've tried a few other STEP files from there, and they look fine, AFAICT, so I am curious why is this one 'special'

[wmayer]

You must check the involved OCCT versions of the FreeCAD variants. Recently I pulled the beta version of OCCT 7.5 and a certain STEP file looked completely different compared to OCCT 7.3

[Pedja]

You must check the involved OCCT versions of the FreeCAD variants. Recently I pulled the beta version of OCCT 7.5 and a certain STEP file looked completely different compared to OCCT 7.3

Well, that's the confusing part
According to 'About' thingie, both use OCCT-7.4.0, and the same thing happens with my 0.19 build with OCCT-7.4.0p1.
[off-topic] So by the time OCCT-7.5.0 comes out of beta with proper release, FreeCAD will build with it? Neat

[wmayer]

According to 'About' thingie, both use OCCT-7.4.0, and the same thing happens with my 0.19 build with OCCT-7.4.0p1.

OK, so in this case it must be a difference between official FreeCAD and realthunder's fork. But I can't help you much in this case. It's probably best to ask realthunder directly.

So by the time OCCT-7.5.0 comes out of beta with proper release, FreeCAD will build with it?

Yes, it does. There was a major API change of the Progress_Indicator class and for now I have disabled its usage in FreeCAD when building with OCCT 7.5. I will prepare a proper port at a later time...

[Pedja]

Mystery solved
With "Use LinkGroup" enabled in STEP import preferences, it looks the same as in RT's branch.
I apologize for wasting your time, I should've picked up on that way earlier, since it's clearly visible in the screenshots that set import options
are different, but I missed it.

[Kunda1]

Please mark this thread [SOLVED] (edit the 1st post thread title)

[easyw-fc]

Mystery solved
With "Use LinkGroup" enabled in STEP import preferences, it looks the same as in RT's branch.

LinkGroups are slightly different in the actual branch and in RT branch.
There are two very old PRs that would need to be merged to have the same behaviour as the actual RT branch...

certain STEP file

@Werner would you mind to have a look at those PRs? (I know they are big ones...)
(Geo)Group behavior changes
Plain/Geo group behavior change and related 3D visualization/selection enhancement