VRay Wirecolor or MultiMatte Element showing through a refracting object

[henryrolls]

Hi there,

I'm wondering if any of you can help.

I'm trying to produce a composite image of a snow dome (you know, one of those paperweights full of water), and I want to get a muli-coloured mask so I can select the various internal components in Photoshop.

 

I know I can either use MultiMatte Element or WireColour (the objects have unique object colours and Object IDs, but my problem arises because the dome (which refracts) hides the colours of all of the refracted objects inside.

While the alpha channel shows through the dome, the objects inside are all green (the dome's mesh colour).

 

I need to have the refracting dome in place as it distorts the objects inside, I uncheck 'Visible to Camera' but keep 'Visible to Reflection\Refraction', the internal objects

 

Does anyone know of a simple solution to this?

Many thanks,

Henry

[Corey Beaulieu]

Render it the way you need it for the Final Render and Render Elements and then render it again without GI or lights and turn off the glass dome to get your Selection Elements. Sounds like a pain, but it's the fastest way. Without GI or lights, it should render really quick too.

[henryrolls]

Thanks Corey,

Forgive me if I'm not understanding you, but if I turn off the glass dome the objects inside aren't refracted properly, so their positions on the selection elements are different to the final render.

[henryrolls]

I suppose one option I could try is to duplicate the scene and manually assign a self-illuminated colour to each of the components. Bit of a ballache but it's a solution nonetheless.

[Corey Beaulieu]

Ah. I see... I miss understood you. I know you can use the VrayDirtMap to create mattes for reflection, but I'm not sure about refraction. I would start there and/or in the VRay Properties look into Matte Ref/Refraction options.