bump maps are do not change geometry
The geometry does not need to change, the cornea only have to “appear” to stand out a little to get its own little specular highlight… and as said above, the cornea going “out” is not the important one, its the iris going “in” that is
/Z
I think one thing that is being overlooked by a lot of people is the thin black outline around the iris that pixar seems to have…
the only special about pixars eyes that i can see is that the colouration(rainbow,iris(?)) receives light from external light sources. other then that there is only one big sphere with textures.
NOTE: PLEASE READ…
Hey all, well, it seems like there has been some debating, argueing, and discussing, etc. in here. Well, I started this thread to figure out the way PIXAR does their eyes for if you really look closelly, and use a normal model, and use an eye you create, and then put the same model with a Pixar eye, emotion, personality, and feeling starts to comes from that model. Yes there are technical things involved with making the perfect eye, and there are many different way at approaching them. What was unique about this was that it involved only 1 shader thrown on any old eye. We had someone from PIXAR who wrote this. No modeling, no textures! Thats the great things about PIXAR is that you can achieve a great look without all the extra nonsense many people go about doing. That is fine, if you all noticed, this thread has over 100 replys in about a weeks time, all relating to this subject. Me and im sure many others were interested on the how to’s as well as understanding and shwoing own examples the same time. I feel, instead of all the praise and all the hype that goes on in here for someones model, or great texture work, why not try to get many creative heads together and figure out how to create the eye. I think by the lengeth of this thread, there is enough information to tell you how to do it, as well as many great links to modeling, texturing, and creating realistic looking eyes as well. With all this said, im glad I created this thread for it helped me a great deal with understanding how an eye really makes that big of a difference, no matter how Star Wars or Pixar it is… That is my 2 cents…
shaun
TheSEL
hi all.
I’m not sure how this will be useful to real 3D artists, and I guess this thread has said all that had to be said, but my experience using a pseudo-3D package called Zbrush has produced the following specimen:
the eyeball is a 3D sphere. it was colored (you can see the eyeballs textured in flat colour on the upper right, with a completely flat material attached to them, so that no 3D information show) and then given two materials:
a dim, kind of glossy “jelly-bean” shader for the pupil and the eye white, and a highly glossy “gel-shader” material, with a modified specular diagram, for the iris.
the eyes are lit by two sun-lights, a bright one placed on the top left, and a dimmer one placed bottom right.
all in all, it took 15 minutes to put together and render (with Zbrush’s mediocre renderer), but I think the result is very interesting.
PM me in the highly unlikely case that you need any more information on this.
Heres something I whipped up in max… the Shellac material is a good help to make the glossy finish… the iris is a gradient ramp w. a bunch of colors w. noise on… and a ton of submaps and stuff…
The “sneaky” stuff lies in a bumpmap that depresses the iris “inwards” so it gets its specular reflection on the “other side”… so geometry here is pure sphere, all is material.
/Z
looks very cool from the front but awful from the side.
btw. havent anyone with lightwave tried to do this with procedurals? (hmm, typo :))
Is this any better? (although I think eyes modelled w/o depth inherently looks a bit wierd from the side)
/Z
An update, they can now dialate, and can be linked to lights. Not much else is different, slightly different iris too.
see you,
Farley13
/*
non-identical eyeballs.
is performed.
Nov 1991 - crude written of "eye" by lg for Herman's eyes for
"Graphic Violence". Original version hard coded in C.
Dec 1993 - "eye" modified by lg to clean up a bit.
10 Jan 1994 - recoded by lg in correct shading language.
28 Jun 94 (lg) - revamped to add veins and iris mottling, renamed
"eyeball"
7 Jan 95 (wave) - changed name to LGEyeBall for namespace reasons...
8 Jan 95 (wave) - changed Ciris line to fix bug Larry figured out and changed defaults
27 Feb 95 (wave) - changed PO line to fix bug Larry figured out to actually *use* index
surface
LGEyeBall (float Ka = .75, Kd = 0.75, Ks = 0.4, roughness = 0.1;
color specularcolor = 1;
color iriscolor = color (.135289, .084323, .372417);
color irisoutercolor = color (.403882, .343944, .68276);
color irisinnercolor = color (.065142, .040605, .179311);
color eyeballcolor = color(1,1,1);
color bloodcolor = color(.8,.05,.05);
color pupilcolor = 0;
float pupilsize = 0.05, irissize = 0.12;
float bloodshot = 1.0;
float veinfreq = 8, veinlevel = 4;
float index = 0;
)
{
#define snoise§ (2*noise§-1)
#define MINFILTERWIDTH 1.0e-7
color Ct;
point Nf;
point PP, PO;
float i, turb, newturb, freq, f2;
float displayed, newdisp;
color Cball, Ciris;
float irisstat, pupilstat;
float bloody, tt;
float ks, rough;
float twidth, cutoff;
/* Calculate an appropriate filter width for antialiasing */
twidth = max (abs(Du(t)*du) + abs(Dv(t)*dv), MINFILTERWIDTH);
PO = transform (“object”, P) + index;
/* Figure out where we are in the eyeball. Use the following variables:
/* If we’re somewhere in the white part and it’s potentially bloody,
Ciris = mix (iriscolor, irisoutercolor, smoothstep (irissize*.8, irissize, tt));
/* If we’re somewhere in the iris, calculate the iris pattern, which is
/* OK, now calculate a surface texture color (Ct) based on where we are
/* Make the eye a little glossier on the iris and pupil /
ks = Ks * (1+2(1-irisstat));
rough = roughness * (1-.75*(1-irisstat));
/* Now shade like plastic, but using our calculated surface color and
…
there is most definetly a newer updated shader that they use at Pixar…but this is how they write the shaders…then compile them.
hey fluxgrafx,
your mel script sounds interesting, I think ill give it a try to see where it takes me. Tnx for posting it up. As far as everyone else in here. It seems like we have every eye with almost every program known to man with 3d.
----------Please READ---------
I feel that the PIXAR eye has been figured out and many people are close if not have the answer already. Im curious what they look on really models you all are working, or even realistic eyes!!! Sort of a new topic, but it can bring some realistic and interesting results, post finished products if you have them…
TheSEL
I need to get back to work! :eek:
hey…this is actually not a mel script. this is pure programming (…Original version hard coded in C…)
it is for use with their software etc. i did a decent amount of fooling around/study with BMRT a little while ago, that’s how I know about it. It is almost the same as Renderman except it uses raytracing instead of shadow maps. It uses the .rib format for output…— rendrib -d 4 file.rib
oh yea…also it is DEFINETLY not mine. It was originally written by Larry Gritz, one of the people who helped to invent 3D graphics and programs from what I understand.
K, this link might already be given, if not it might be interesting, one big thread on eyemodeling, check it out !!!
Originally posted by derwolpertinger
interesting discussion!
so i also worked on an eye but tried to do it only with the use of shaders not geometry. but i’m not totally satisfied cause i can’t manage the iris to cast a shadow so that it is darker in the upper area and lighter in the lower area. i’ve used a bump map to simulate the geometry. tell me what you think and how i can improve things plz.
Do PIXAR really do it ALL in shader? Been trying to visualize it in my head but can’t. Looks like it’s time to brush off those renderman skills
Remember rendermans extensive displacement abilities… hence you can take a sphere, and write a shader that turns it into a human head with ears, eyes, hair, e.t.c. all perfectly modelled…
/Z
