Oddity with node setup, and confusion.

posted to: Scratches & Bump

Despite how well I follow the video the results never really are the same at times, I suppose it's the version differentiation with respective changes that may be the underlying cause. Here's a shot of how the gradient between white and black never switch to "grayscale" in the color-ramp. Not to mention the gizmo in the end becomes VERY dark for unknown reason.

https://i.imgur.com/S8wHNdq.png

https://i.imgur.com/QS7b54j.png

I hate being stuck on the smallest of things.

I'm also confused to why the scratch texture needs its normals linked to several BSDF nodes instead of just one.

  • Sid Lilja(ohem) replied

    Okay I think I managed to correct it, I don't know how or why it works but yeah it's correctly represents what the video shows.

    But I'm still confused to why connect the same normal map unto several BSDF.

  • Kent Trammell replied

    The ability to plug in unique normal maps per BSDF node gives us flexibility as artists. For example, in rare situations you may want a diffuse BSDF to have a normal map while a glossy BSDF does not, like a clear-coat effect.

    The best example to demonstrate this is "figured" wood. It's a natural phenomenon occurring in wood grain that produces a 3-dimensional illusion. It looks like the grain is wavy but it's actually perfectly smooth/flat to the touch. Watch the first 15 seconds or so of this video to see what I mean.

    To create a figured wood material with Cycles, you would plug in a wavy normal map into the diffuse BSDF and then mix a glossy BSDF on top without that normal wavy map to achieve the figuring effect.

  • Kent Trammell replied

    Forgot to say "curly" and "flamed" are subcategories of wood figure.

  • Sid Lilja(ohem) replied

    Ah so you mean if I had a Glossy BSDF with wood texture (context) it'd have appear like glass instead of a finish? So by using Diffuse the illusion is retained?

    Or did I misread your reasoning?

  • Kent Trammell replied

    oohem To clarify my example, a figured wood texture goes into the Diffuse color with a wavy texture going into the diffuse normal socket. That will make it appear wavy but not shiny. Then mix a Glossy BSDF with a solid white color at maybe 0.1 for the mix factor and no normal input. That combination of normal-bumped diffuse + normal-free glossy can produce that kind of figured wood effect.