randomly assign colors per object from a custom color palette

[aaronfross]

Hi,

The Arnold Color Jitter node is helpful, but ultimately, randomizing value, hue, saturation doesn't give aesthetically pleasing results. Randomizing hue, in particular, looks awful. There's no way to get harmonious colors. It all ends up looking like harsh RGB hue noise.

What I would love to see is an easy way to randomly map a palette of custom colors onto objects. Kind of like how we can remap texture colors with a gradient ramp using the Source Map input.

Thanks,

Aaron

[laurent_gibert]

Interesting idea @aaronfross, thanks for your contribution.

[masterzap]

As of today you will be able to do this with the OSL "1-of-10 (color)". If you need more than 10 the shaders can be cascaded.

/Z

[electrotoast_old]

This is Implemented as part of OSL integration in 3ds Max 2019. Thanks for the Idea!

[aaronfross]

Thanks guys, for some reason I didn't get notification when you posted replies.

OSL is fantastic.

[onitreb]

Where does the randomization part come in?

The OSL is a list of colors or maps that you can choose explicitly.

The OP asked for a way to randomly assign the colors. Am I missing something?

[electrotoast_old]

@aaronfross Were you able to use the OSL implementation as described? Maybe you have a tutorial on it already?

[onitreb]

This is the OSL (the "1 of 5" version). How can this be used to randomly assign these colors to objects (or elements)?

[aaronfross]

Hey guys,

I do have a tutorial for this, I've unlocked it on LinkedIn Learning. The key is you need to use the Random Index and Node Handle maps to generate random numbers from object scene identifier numbers ("node handles"). 

https://www.linkedin.com/learning/embed/3ds-max-tips-tricks-and-techniques-2/shading-per-object-with...

[onitreb]

Thank you very much. Terrific tutorial.

I'm curious if anyone has an idea how this could work on an element level? Specifically using the scatter modifier, which produces a single object built of individual elements.

Thanks!

[onitreb]

I think I answered my own question. It's the OSL "MaterialID" node.

Here is the slate editor layout, for a quick reference. But definitely check out Aaron's tutorial.

[onitreb]

Me again. 😛

I've assigned this to a scatter object with a MaterialByElement modifier and I'm not seeing the output (namely the random part) of this in the viewport. I see the correct colors in activeshade. 

Is there any workaround for this? Is viewport visibility likely to be implemented in the future?