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gnomon believable eyes but with arnold renderer?

Hi i'm new to all this and for class project i'm trying to use gnomon's believeable eyes tutorial for my characters eyes but they use mental ray and i'm using arnold so can only use arnold shaders.

Thing is they use a really really really really old version of maya and use a U ramp to tell the eye shader how much of the eyeball is see through.

Thier maya also put a rainbow of colours on the eyeball and the ramp slider had that rainbow too. The slider in the newer maya is a black and white one and the eyeball in my viewport doesn't have black and white on it to show the ramp like the tutorial either.

Basically I can't tell what this ramp is doing or even if i'm plugging it into the right thing or if arnold uses ramps.

Basically how can I use an AIstandard shader to make an eyeball where the front where the iris is will be transparent but the rest of the eyeball is opaque?

Thanks in advance for any help you might be able to give :)

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  • DireWolf
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    Flexibility is the key... create an ordinary lambert or surface shader, connect the ramp to it's color normally for preview. You can even duplicate the eye so you won't have to reapply your AI shader back and forth.
  • peteed1985
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    DireWolf wrote: »
    Flexibility is the key... create an ordinary lambert or surface shader, connect the ramp to it's color normally for preview. You can even duplicate the eye so you won't have to reapply your AI shader back and forth.

    Thanks for that, i'm thinking the tutorial is useless for me since my eyeball is a polygon but theirs is a nurbs. The U ramp isn't working on the lambert since nurbs and polys seem to do UV's differently. This leaves me with no clue at all how to do it because I do need something like a ramp effect had on the nurbs but on my polygon.
  • DireWolf
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    It's just their UV don't match up. An easy way is to create a nurbs sphere and convert it to polygon and you should have UV lay out very similar to the tutorial. You can also try unfold the eye yourself.
  • peteed1985
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    DireWolf wrote: »
    It's just their UV don't match up. An easy way is to create a nurbs sphere and convert it to polygon and you should have UV lay out very similar to the tutorial. You can also try unfold the eye yourself.

    Managed to get it working by mapping it in the X axis instead of the Z I was using but I have a bit of an issue here.

    Viewport 2.0
    vIYdZ8E.png

    Legacy default viewport
    4UG65fp.png

    3rd and 4th are with smooth and linear interpolation arnold renders
    Za3ySgh.jpg8zEiX45.jpg

    no interpolation arnold render
    5cS7jQi.jpg


    Legacy default viewport is showing basically the results I want in renders, but no matter what I do theres no iris showing in renders and even with no interpolation which seems correct because theres black there I can't see the iris in an arnold render plus I need smooth interpolation not none.

    I am putting the ramp in the right place aren't I?

    refraction > opacity checkerbox
  • DireWolf
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    Let me try. Haven't used Arnold all that much.
  • DireWolf
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    Ok I think I found it.

    Select your geometry. In the shape's attribute you'll see a tab called Arnold. Uncheck "Matte" and it should render what's behind it.

    Here I threw an orange aiStandard to the sphere inside.
    0OEMel8.png
  • DireWolf
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    In the Arnold tab, if you scroll down a bit you'll find a Subdivision tab.

    This is for render time smoothing. Set type to catclark and set Iterations to 3. See what happens.
  • peteed1985
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    DireWolf wrote: »
    In the Arnold tab, if you scroll down a bit you'll find a Subdivision tab.

    This is for render time smoothing. Set type to catclark and set Iterations to 3. See what happens.

    Whole things gunna be rendered 3 smoothed in the end :)

    I found the part Matte wasn't ticked but opaque was on the shape attributes, I thought it was an issue with the shader not the geo haha. I'm still new to all this.

    Sadly the Viewport 2.0 seems to not show arnold shaders opacity so I get a solid colour eye unless I use legacy viewport but at least it renders right lol.

    I'm also having the eye completely disappear in the legacy viewport if looked at directly from the front or back but rendering fine then too.
  • DireWolf
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    You should connect your ramp to a separate "check" material. Color is all you need, just to give you general idea where your ramp is. Fine tuning could be done with render.

    I tried connecting a ramp into aiStandard's color and it does show up both in legacy and 2.0
    http://imgur.com/aPL5dr1
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