question

Evan Gill avatar image
Evan Gill asked

Projected Decals like Unreal and V-ray

Is there any way to project a material onto a mesh and/or multiple meshes without changing the material of those meshes or messing with their UVs? Ideally with the ability to only effect certain channels, I.e. only project a normal map onto a piece of metal so it's base color/roughness showed through. Or say I wanted to project a mossy decal across a few different rock meshes and have the normal map for the rock meshes blend with the mossy decal normal.

We do this allot in Unreal and it's awesome.

The best I can think of is a conforming mesh with transparency, but this is obviously problematic in workflows, and doesn't pass through the underlying material channels.

Thanks!

materials
10 |600

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Lee Griggs avatar image
Lee Griggs answered

I presume you have tested the following shaders?:

mix shader

mix_rgba

layer_rgba

10 |600

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Evan Gill avatar image
Evan Gill answered

@Lee Griggs Thanks, yeah I'm familiar. I don't know of an easy way with those to have your decal project across materials/meshes. Say I had a brick wall with metal ducts and rubber wire meshes on top of it, and I wanted to spray-paint over everything. It would be allot of material and UV work to get that working.
With a projected decal it just works quick and easy. Some examples.
https://youtu.be/PjZEDzQuan0?t=84
https://youtu.be/5kzR_TdMGU4

10 |600

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Lee Griggs avatar image
Lee Griggs answered

Maybe the uv_projection could help?

10 |600

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Write an Answer

Hint: Notify or tag a user in this post by typing @username.

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Welcome to the Arnold Answers community.

This is the place for Arnold renderer users everywhere to ask and answer rendering questions, and share knowledge about using Arnold, Arnold plugins, workflows and developing tools with Arnold.

If you are a new user to Arnold Answers, please first check out our FAQ and User Guide for more information.

When posting questions, please be sure to select the appropriate Space for your Arnold plugin and include the plugin version you are using.

Please include images, scene and log files whenever possible as this helps the community answer your questions.

Instructions for generating full verbosity log files are available for MtoA, MaxtoA, C4DtoA, HtoA, KtoA, and Kick.

If you are looking for Arnold Documentation and Support please visit the Arnold Support site.

To try Arnold please visit the Arnold Trial page.

Bottom No panel present for this section.