A, this old chestnut, yes i heard that Pixar use there own custom shadders Chris's system looks amazing !
I have seen it done one other way, ( DISCLAIMERS: i was only given a very brief break down of this rig, what follows may not be relied on as instructions but more as pointers, a good rigger might be able to make something of this. ) You take an object that is half sphere half cylinder (the cylinder part will be the iris eventually) Then you apply a lattice to the cylinder part, in a manner that it reforms a perfect sphere with the rest of the mesh (this can be done mathematically, for extra precision but i'm not sure exactly how). The idea is that when you mute the deformers you have a flat surface (on the cylinder end) to do your blend shapes, which then are easier to balance and create less distortion. create an other sphere to act as the transparent membrane. put the whole thing inside a Lattice, that will be used for rotation, and another lattice after that that is used for deformations and translation. Hope this can be of use to someone. This method was used in this film http://www.youtube.com/watch?v=zTQ7rd8aswg On 18 November 2013 23:37, Adam Seeley <[email protected]> wrote: > Hi, > > Sounds like a job for Booltrace, a mental ray boolean shader. > > It's a bit of a head scratch to figure out how to get the geometries to do > what you want, but it should work fine. > > You can get it here, from the treasure trove that is > http://rray.de/xsi/ > > I used it to create Gems embedded into Rock some time ago and needed to > create a similar effect. > > Have a google for more info on it. > > Adam. > --------------------- > http://www.linkedin.com/in/adamseeleyuk<http://www.linkedin.com/profile/view?id=21162305> > https://vimeo.com/adamseeley <https://vimeo.com/album/2280465> > > > > > ------------------------------ > *From:* Christopher Crouzet <[email protected]> > *To:* Softimage Mailing List <[email protected]> > *Sent:* Monday, 18 November 2013, 11:02 > *Subject:* Re: Non-spherical eye while keeping iris circular > > Hey Enrique! :) > > An idea could be to fit a NURBS sphere to the shape of your outer eye, > then use it to constrain the deformers onto its surface, and finally slide > those deformrs using UV coordinates. > > I did something like that a whiiiile ago: http://vimeo.com/2466613 > In this video the eyes are spherical but they definitely could be anything > else. > > > > On 18 November 2013 11:56, Enrique Caballero > <[email protected]>wrote: > > hey oliver, > Thanks for the reply, that would work if the pupil was a separate piece > of geometry and is exactly how i do it on other characters. > > Sorry I should have been more specific. > > Basically I'm trying to make the Pixar eyes. Where the iris is cut into > the eyewhite, and actually goes inside of it. This one i have not been > able to figure out for a while. > > > > On Mon, Nov 18, 2013 at 6:51 PM, olivier jeannel > <[email protected]>wrote: > > I'm not a specialist in toon, but I would keep the Lattice on the Eye (the > white deformed sphere) and make a separate Iris object that would be > "shrinkwarped" on it. So that the Roundness of the Iris wouldn't be > affected by the stretch of the global eye. > Maybe a ClosestLocation in Ice would give even more control and speed... > > > Le 18/11/2013 10:58, Enrique Caballero a écrit : > > Hey everyone, > Does anyone have any tips on how to rig a non spherical eye while > maintaining a perfectly circular iris? > > I have done it in the past with starting with a spherical eye, using a > lattice to deform it and then using blendshapes to counter the squashing > effect on the iris. But this method is clunky and you can see discrepancies > in the interpolation. > > Any tips would be welcome, this question has bothered me for some time. > > -E > > > > > > >
