Yet another thread on glitter materials

[AlejandroCambra]

Hi!

I’ve spent the last couple of days trying to get a glitter material that seems believable, but this is what I’ve got so far:

As you can see, it looks pretty flat and boring. Here’s my nodes setup:

(The section circled in red is the normal trickery I’ve done to simulate the microfacets).

And this is what I’d like to achieve, with a couple of annotations added:

Any ideas on how to get right those highlights and reflections? Note that I do not want glitter covered by a reflective surface, as we would find in carpaint or cases like this, but the rough, “raw” kind of glitter you’d see on a Christmas ball like that in the last image. This other thread, on the other hand, showed something nearer to what I’m looking for, despite not achieving it procedurally. So, any advice to get this done only with nodes? I know this is a tough topic in shading .

Álex.

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EDIT: I’ll mention here @Secrop, @minniejo and @tomjk since they were relevant participants in the quoted threads. Maybe they can add something interesting!

[unyxium (Martin Ibbett)]

Firstly, the reference glitter is much shinier than your render. I think it is to do with the roughness you have set up in the principled shader being too much. The reference appears to be quite bumpy, giving the speckled appearence and not through variation in material roughness. All the glitter is uniformally reflective, but the bumps break it up.
The other thing is that the render’s lighting is not bright enough to make the glitter reflect brightly enough. Your scene needs better lighting (maybe a hdri instead?) to see the glitter properly.

[moony]

A couple of things.

1. Make sure you arent using low clamp values in your render panel - especially for direct light. In fact, i,d probably turn direct clamping off alltogether (set it to zero).

2. To get a good glitter effect you’ll need to add some fog glow and/or streaks in compositor.

Even so - convincing glitter is a difficult effect for Cycles at the moment. There are some good papers on this subject and I hope one day that Cycles can incorporate something like this.

http://people.eecs.berkeley.edu/~lingqi/

[pixelgrip]

have played a bit.not like the reference,but a interesting procedural version imho.

[icyou520]

This may help a little

https://blender.stackexchange.com/questions/45358/how-to-create-a-glitter-texture

[moony]

Not like the reference - but this is pretty neat in Eevee

Doesn’t look anywhere near as good in cycles though.

[CarlG]

In Eevee, another trick you can do is feed a glossy node into a shader2rgb node, and use that to further mask the effect. I.e. showing a separate glitter effect only on the parts that would smoothly reflect the lightsource.

In general, how to make an orange surface produce bright reflections? Make the light sources brighter. Use the voronoi trick from the video above (without the top coat gloss obviously), possibly add a hint of white reflections to the regular glossy shader. That’s a trick I use to add “long tail anisotropic highlights” to really spread it when the main glossy isn’t rough enough to support high aniso. I’m not sure how it would work out here though, can’t test atm (no proper PC).

[AlejandroCambra]

Thank everyone, but none of your advices made any improve .

@unyxium, if I increase the Roughness too much the glitter appears noisy. It was (and still is) a single value, anyways.

@moony, I already had my clamp values set at 0. The glow didn’t help that much. It actually made the render less realistic (a little “cartoony”). Thanks for the video, but I watched it a few days ago . And yes, it is not like the reference, as you said.

@pixelgrip, isn’t that material too “metallic”? I mean: you don’t have sparkles there, but only bumped flat shapes.

@icyou520, your answer was interesting! I didn’t know what the Incoming socket of the Geometry node did, and those uses seem very powerful. Your example doesn’t meet my requirements, however. Unfortunately .

@CarlG, I’m using Cycles .

Anyway, I’ve simplified my nodes a bit (converting the metalness to a simple value input, basically) and I’ve also increased the “Normal Perpendicularity” parameter in order to create a slightly more even surface, trying to get the reflections more defined. Apart from that, I gave a little more strength to the light (a sun light).

Here is my previous try:

And here is my improved material:

I think it is fairly better than the first one, but it still lacks those bright and clear reflections. I’ve tried to mix in a glossy shader with the colour set to white, but the shiny bits end up being almost unnoticeable. Jargh. Any other idea? And thank you all again for your contributions! They are highly appreciated .

[moony]

Can you post your blend file of the latest material - i’ll have a play.

Can’t think of anything specific off the top of my head - but I have messed with materials like this in the past and something might come back.

[AlejandroCambra]

Sure, here you have it :

Glitter.blend (894.4 KB)

[moony]

No change to material - just a few tweaks to lighting and some compositing.

[AlejandroCambra]

Hmm… Still looks fake to me xD, could you share the nodes? I think the glares are too strong, but there are some interesting white sparkles.

[moony]

I changed the light to point rather than sun. Turned down the world illumination - and added these compositing nodes.

You can tweak these to your own taste

[AlejandroCambra]

Thanks! I’ll give it a shot .

[CarlG]

@AlejandroCambra

Still looks fake to me

It’s about as close as you can get it. The real thing is covered by rather large (real) particles rather than being a completely smooth surface, and as such will not produce effects like shadowing and interreflections. There is actually a limit to what can be achieved via materials alone.

[moony]

^^ yep. I have tried covering a sphere in a particle system, but the effect wasnt all that good. I simply couldnt get the coverage needed to make it look convincing. Maybe I need to have another play.

[AlejandroCambra]

Yeah, I know that. I fear there are even some features that contradict each other (e. g. little, sparse sparkle reflections and at the same time bigger, coherent ones). So yes, we tried. At least we didn’t fail miserably!

[icyou520]

Wouldn’t it be a similar problem as THIS ?

I wonder if you would have better luck with LUXRender.

[CarlG]

I doubt it. Cycles is afaik equally good at “getting the rays” to the camera. Where it fails is “getting the rays” to the scene. Camera will pick up these highlights, the the scene/floor wouldn’t be directionally directly lit by them.

In terms of geometry, might want to find (or procedurally construct) a bumpmap based on some sort of surface treatment (i.e. sandblasted or cast, don’t know) that would give this appearance, and use that as a basis for a high detail displacement.

But yeah, some glare and shallow depth of field will probably help too.