"Principled v2" feedback/discussion thread

[brecht]

The manual has been updated now with the new parameters.
https://docs.blender.org/manual/en/4.0/render/shader_nodes/shader/principled.html

It also includes this explanation for Random Walk (Skin):

Random walk method optimized for skin rendering. The radius is automatically adjusted based on the color texture, and the subsurface entry direction uses a mix of diffuse and specular transmission with custom IOR. This tends to retain greater surface detail and color and matches measured skin more closely.

@Alaska

To fix that, there would need to be hard limits in the UI (E.G. You type in -1, and it resets to 0). I might be missing something, but I don’t believe Blender supports this at the moment.

Node sockets don’t support hard limits currently, unlike other types of properties. This should get implemented at some point.

@Gurra

Well you can set RGB values to higher than 1 as well, so don’t see why not just use that?

Because I don’t think the color is representative of what it’s doing. High values will show white, low values black, regardless of the color tint.

But, we should really add Red/Green/Blue labels to those buttons. We just haven’t gotten to it yet.

@PetrTarasov

May be one year later this variant for principled node UI become actual?

There is a lot of discussion about this earlier in this topic. For me the main reason to stick with panels is to have a single consistent mechanism for organizing properties throughout the user interface.

"Principled v2" feedback/discussion thread

We use panels throughout the UI to organize settings. Remember that geometry and shader nodes are also editable from the properties editor, where we already use panels, and so they would fit in naturally. If the proposal is to be inconsistent with that, there should be an argument for why it’s significantly better. And it should ideally then also explain how the problem of complex node groups will be solved, if the same method can be applied to that or if it would require us to implement and ma…

@Alaska

This seems to be the main cause for issues. Disabling this optimizations gives me results closer to what I would expect.

I’ve added it as a to do item in the Principled v2 issue to look at this again.

@pixelgrip

Why is that clamped?

For the reason explained here:

"Principled v2" feedback/discussion thread

Subsurface scattering works by specifying the desired color and radius on the surface, and then we figure out the appropriate volume scattering and absorption parameters that will produce the color and radius. That way you can texture it just like any other diffuse surface. We currently only have a numerical fit for the 0…0.9 range. Possibly it could be extended, but this covers the most common types of materials that subsurface scattering is meant for. With a material that is very highly forw…