Strange artifacts in my clay render

[maarten_vis]

Hi all,

Having a strange issue with a model I have to work on that I got from someone else. I can't share the source file because of my NDA agreement.

So I want to make a clay render, but these weirds artefacts keep showing up. (All the white areas above the grey model) I think they're material effects on objects that should be hidden by the section plane. (As you can see they show up in several of the render layers I've included)

I can't seem to figure it out. Hope someone can help!

Thanks,

Maarten

[wzfwzfwzf]

You need to check the front and back of your material, maybe the back is facing out. Caused the PNG to be transparent in position. Or it is your material setting problem, check what is the material of the empty position of png.Or if you are calculating with GPU, try replacing it with a CPU.

[maarten_vis]

You need to check the front and back of your material, maybe the back is facing out. Caused the PNG to be transparent in position. Or it is your material setting problem, check what is the material of the empty position of png.Or if you are calculating with GPU, try replacing it with a CPU.

Thanks, but why would the front or the back appear at all, as all these objects should be cut out by the section plane?

[natalia.gruzdova]

Hello maarten_vis ,

Please try the following and let me know if any of this help:

• In case you have Contours enabled please try to disable them. Unfortunately this is a known issue with Contours and Clipper and this may be the cause.
• As wzfwzfwzf also suggested you could try to change the rendered engine. Which one are you currently using?
• Are you using Material Override for clay render? What settings do you have in Clipper? As a way to workaround you may try to disable Use Object Material and select a completely transparent material for the Clipper. Just create Generic material and set its opacity to 0.
• Another option is to delete all Clippers, copy the geometry to the new scene and create new Clippers.

Additionally, we can also provide you with an NDA agreement that can be signed by both sides guaranteeing that the file is going to be used strictly internally and for debugging purposes only.

If that is a suitable option to you please open a ticket via https://support.chaos.com/hc/en-us/requests/new form.

[maarten_vis]

Hi Natalia,

I'm not using Vray Clippers, but sketchup Section Planes. And where do I disable contours?

thanks,

Maarten

[natalia.gruzdova]

SketchUp’s Section Plane is automatically recognized by V-Ray as Clipper and you can find it in Asset Editor under Geometries Tab.



Contours option is available in the Asset Editor under Settings Tab.



If you would prefer we could arrange a TeamViewer session so I would take a look at it directly, if that is alright for you please open a ticket so I could send you further instructions.

[natalia.gruzdova]

Thanks maarten_vis for testing suggested options and even further. We were able to determine that the issue was not caused by Contours.

In this case resetting Material Override color to its default (gray) color partially solved the issue, as well as checking for some Emissive materials that had the Can be Overriddenoption disabled that caused artifacts with Clipper.