Linking materials causes loss of detail and definition on renders

[jhiker]

I'm on the latest version of KS
Consider these renders of a section view.

In the first one I have applied a 'toon' material to a component and 'pasted' that material to all the other parts in the scene tree so they are linked. Looking at the render there is very little definition of the part edges and they seem to almost merge together. In some regions it's not at all clear they are separate parts.

However, if I 'unlink' the materials the component part edges miraculously appear and the part definition is much improved resulting in a much more acceptable render.

Nothing's changed except 'link'/'unlink' - surely this should not happen?

[thomasteger]

You may want to increase the line width and/or angle.

[jhiker]

C'mon Thomas, that's no answer...

I may like it just as it is and expect it to work properly 
I've taken time to set the parameters as I want them and the scene with the 'unlinked' materials is just how I want it.

As far as I can see, adjacent parts with linked materials appear to be losing edges and definition.
Is that how you would expect it to work?

Is that acceptable to you, because I don't think that's right.

Maybe it's just on section views, I don't know - this is the first time I noticed it.

[KeyShot]

The toon material is indeed set up to perform a separation based on materials. The reason for this is that often objects are composed of many parts and if we used the parts to separate the elements you would get too many lines. Unlinking materials is a good way for you to control the part separation.

[jhiker]

The toon material is indeed set up to perform a separation based on materials. The reason for this is that often objects are composed of many parts and if we used the parts to separate the elements you would get too many lines. Unlinking materials is a good way for you to control the part separation.

Thank you for the explanation, I had no idea it worked like that. I assumed the separation would be based on 'parts'.
Now I know, I'll 'unlink' when it's appropriate to do so.
Many thanks.