Mia_X Material Transparency problem

# 1 01-05-2013 , 03:56 AM

Registered User
Join Date: Nov 2002

Location: Philippines

Posts: 136

Hello all,

I've a question about the transparency of the Mia_X Material. I have a couple of cans that I wanted to put some condensation on. The can has an Mia_X material, and so do the nParticles that I used for condensation. The condensation material is reflective and refractive. When I render, the rgb looks ok, but the alpha looks like the particles punched holes through the cans. It's an old issue, I think but one I never did get to figure out.

Also, I'm lighting using an hdr image, if that makes a difference user added image

Any and all help would be appreciated. user added image

Attached Thumbnails

Click image for larger version

Name: CokeSmall.jpeg
Views: 685
Size: 200.8 KB
ID: 53899

Click image for larger version

Name: Coke_Alpha.jpg
Views: 665
Size: 182.9 KB
ID: 53900

Last edited by Calvin; 01-05-2013 at 04:00 AM.

Quote

# 2 09-05-2013 , 08:27 PM

Super Moderator
Join Date: Dec 2006

Location: South FL

Posts: 3,522

The only way around that I've found is piping the mia's result into the outcolor of a surface shader. The "Pass Custom Alpha Channel" attribute in the render settings doesn't seem to work and neither does "propagate alpha" in the material settings.

- Genny
__________________
::|| My CG Blog ||::
::|| My Maya FAQ ||::

Quote

# 3 10-05-2013 , 03:46 AM

Registered User
Join Date: Nov 2002

Location: Philippines

Posts: 136

Ok, so I pass the MiaX material result to the outcolor of the Surface shader then apply the surface shader to the nParticles, correct? user added image

I'm wondering if this has anything to do with it being particles. I tested this with a transparent torus around a sphere and the alpha of that was what you'd expect.

Quote

# 4 10-05-2013 , 05:06 AM

Super Moderator
Join Date: Dec 2006

Location: South FL

Posts: 3,522

That's right. And it does seem to be a problem with particles. Standard Maya materials and MR materials handle alpha differently, but didn't think we'd have to deal with this -_-.

- Genny
__________________
::|| My CG Blog ||::
::|| My Maya FAQ ||::

Quote