imported Creo Mechanism models show black surfaces during animating

[Bj]

With about half of the mechanism animations I exported from Creo directly into Keyshot the following happens:
After applying materials that give some form of light reflection and animating; the resulting animation has some surfaces going totally black at some frames. The result is therefore useless. I have tried everything (also different pc's with different sub-versions of Keyshot 4) but no other solution but setting the material of the affected surfaces on "diffuse". See attachment for an example (the top surface of the table in this case). I can even go with the slider in the animation window to the exact frames where this happens.
Does this sound familiar to anyone? Any solution?

[KeyShot]

I believe this is an old bug. Which version of KeyShot are you using?

[Bj]

4.3.10

Thanks for replying!

[Bj]

check out the following animation. Ive set the top surface on emissive, but if you look at eg. the handled next to the top-surface, its kind of flashing (because of black surfaces in some frames).

https://www.youtube.com/watch?v=T-cCHX-OUMU

[thomasteger]

Looking weird. No matter what you should upgrade to 4.3.18.

If you don't mind, please go ahead and send us the scene. We will give it a shot here to see what we are getting in the latest build.

[Bj]

I've also tried in 4.3.18 but to no avail.
I must stress this is not a one off, it happens with half of the animation models I import from Creo (2.0 M90 and previous..)
See attached .bip file.

[Chad Holton]

Hi Bj,

Would you please send the Creo assembly (and all applicable parts) to: support@luxion.com

Use this upload link, if you like: https://keyshot.wetransfer.com/

Thanks,
Chad

[Bj]

Just quickly created and uploaded a simplified example of the earlier model, same problem. I must say I've created these models using "motion skeletons". Perhaps that has something to do with it?
Hoping to hear from you soon.

[Chad Holton]

Thanks for sending, Bj. I checked it out and it all looks fine on my end from what I can tell. I'm thinking it's a mix of your environment (with black in it) and the mirror finish on your part causing the black areas (basically, the mirror finish is reflecting the black areas of the environment). Try a different environment to see (maybe one of the interior or outdoor environments) and/or add a little roughness to your material (under the material's properties tab). Let us know if this makes a difference or not.

[Bj]

Hi,

I've tried several different environments and different material (roughness). Doesnt help 
See the animation I created. Most of the animation is okay, but certain frames just wont render certain surfaces and leave them black!

Ive tried on a Dell3500 (Intel Xeon W3550, Nvidia Quadro 2000), a Dell Precion 390 (core 2 dual, AMD FirePro V4900) and a Dell 3400 (Core 2 quad, nVidia Quadro FX 3450).

Going on holiday for a week now!

cheers.

[TpwUK]

When you get back of holiday, check your model for duplicate surfaces. They do sometimes occur when extruding surfaces so check in your modelling app.

Martin

[Bj]

Moved to Keyshot 5 and still get these black surfaces in certain frames when imported an animation from Creo. Nobody else with this issue? Getting a newer Dell T3600 soon, perhaps this will fix it but I doubt it.

[Rex]

Hey BJ,

Did you check your model for duplicate surfaces as Martin suggested? It looks like there is some strange z-fighting going on at the frames that show black. I'm not a creo user but perhaps the top surface is separate and the mechanism isn't syncing the two parts properly?

[Bj]

Hi guys,
Im pretty sure there are no duplicate surfaces in my models (I only export solid models, if that makes sense).
Ive found out that these black surfaces appear when I import a mechanism in Keyshot that contains bodies that rotate.

Ive created a really simple model and even that produces black spots (complete white environment and ray bounces above 20). The only time I dont get these spots is when I apply diffuse materials.
Im really curious if more people experience the same, so if anybody could animate and render the attached .bip file and post what they see?

[Rex]

Hey BJ,

Thanks for sharing the file. I see the same black areas. I filed the bug with development so it should be fixed for the next update.

Rex