Eye troubles

[WMLeeBo]

Try HRDI. Look for it with Brazil r/s at www.slutterfish.com .

[BrandonD]

It's just a matter of specularity control and reflection maps. Neil Blevins wrote a good tutorial a long time ago about creating "wet" materials www.neilblevins.com which might help. Specularity in general is a reflection driven by the smoothness of a surface. The surface of the human eye is normally wet and therefore very glossy and reflective. However in CG, I don't think you need to go overboard and do raytracing. Try very high specular strength/glossiness settings. Then add a spherical environment map to bring in the reflections. The trick will be to limit your refections and not make it too exact. Try a very low resolution map so you just get some shape and color and no recognizeable detail. You might want to mask the reflection map with a Falloff Map using the more physically accurate Fresnell setting.

[Seven]

Thanx for the reply. Interesting

Does anyone know of an actual tutorial that will take me through it step by step.. to a conclusion. To a final eye like object. It might only be the basic principles in a tutorial but at last i can follow it, then apply that to my eye. I find reading info like on the web page of www.neilblevins.com very interesting but i need a actual thing to do to help me. Im very much a 'do' person.

The thing that gets me (for example) is there always seems to be a reflection, etc at the bottom of the eye.. by the bottom lid. Now is that a texture map as in a reflection or spec telling the light to reflect there? Or does this techqiue apply to the whole surface and what angle you view it at, light etc determins which parts are lit ?

Make sense :) sorry i cant explain myself very well.

Thanx

Sev

[Gonzo The Great]

To get complete control over the glossy nature of eyes and to give them a sense of wetness:

1) you can copy the eye spheres.
2) enlarge them a fraction
3) attach the the new sphere to the original eye. (Of course you can dupicate as element too)

Its best to attach it to the oringinal (especially if you have a odd shaped head model and you need something like a FDD BOX warp (or modifier) on the thing and alters shape as you control the rotation with something like the Look At constraint.)

4) Give it a unique material ID

Reflection Map:
5a) For complete accuracy - Render the environment six times for the Left, Right, Front, Back, Floor and Ceiling and make a box image reflection format.
5b) For a character of mostly mid-shot shot scenes - just any image of a similar environment.
5c) Raytrace 10-40%

6) Change Mat. ID

Refraction Map:
7) Raytrace 10-40%

8) Change Mat. ID

Extended Parameters:
9) Adv. Transparency ... In @ about 40-60
10) Index of Refraction ... reduce default 1.5 to about 1.15- 1.25 (The help files have a rough guide of IOR values and crap they are good for)
11) Change Opacity (but not too much)

Ciao

[Seven]

Thanx alot Gonzo

[Seven]

me again :) ive got some more questions about Gonzo's reply.

Ok i get copying the eye, enlarging it abit and attaching it to the original sphere.

Then gonzo says give it a uniue material ID, now does everything on from this apply to the new material ID ? and to the new enlarged sphere ive created?

Wouldnt the new sphere have to be transparent in order for there to be a point in me making it ?

Relfection mappain easy...

Does the refraction have to be on a new ID ?

I also dont get what you mean by adv transparency.

Sorry for acting all stupid, never really done anything like this before.

Thanx

Sev

[Gonzo The Great]

Then gonzo says give it a uniue material ID, now does everything on from this apply to the new material ID ? and to the new enlarged sphere ive created?

The new Mat ID shouldn't apply to all previous materials prior or after. It is a little fiddly..... and is amoung the more stupid of stupid things in max.

Test it.... pick Select by ID. will clear selection on and go through your numbers before apply materials.

And when you apply a UVW modifier change the Mat ID. When you collapse it won't loose the UVW information.


Wouldnt the new sphere have to be transparent in order for there to be a point in me making it ?

I also dont get what you mean by adv transparency.

The image supplied should show ya where it is... and you will see why when you change the ADV Trans value why you don't need to change the Opacity greatly.

DON'T confuse opacity and transparency. That are not the same thing. Opacity should be called Invisibility value or something.

Now one problem if you choose 100 opacity is that you can't see the smaller sphere underneth and you don't know where the pupils are when animating. You have the option to reduce it slightly (95-99%) or select the element in Sub-Object mode and click HIDE.

To avoid the reflections dominating the Iris and Pupil and more so the White areas and near the lower and upper Eyelids - Multi-layer anisotropic should be used and create a new quick opacity map (of Black, grey and white values only) to be applied within Reflection and Refrection own rollouts.

Of course you will need to tweak stuff.... where I circled is typically where I apply the supplied Refmap.gif (in 3dsmax4/maps/reflection dir.) just to add flaws like in real life.

[Gonzo The Great]

Now one problem if you choose 100 opacity is that you can't see the smaller sphere underneth and you don't know where the pupils are when animating. You have the option to reduce it slightly (95-99%) or select the element in Sub-Object mode and click HIDE.

Sorry - I meant if it 100% opaque you won't be able to see it in the VIEWPORT. The render will do what it is told.

[Seven]

Gonzo you are a star.. even with pictures

/me hugs Gonzo :)

[Seven]

Gonzo have you got an example (image) of an eye you have created useing this method ?

I would very much appreicate seeing one if you have.

Sev

[Gonzo The Great]

Yeah alright.

Come back in a few days... I am working on a non-photorealistic project at the moment and I'll have to open an older file and re-render.

Its pretty old - something I did about 2 years ago but still ok.

Hey! - Come to think of it.... I've never seen it with Brazil's GI. Should be interesting.

[Seven]

great... i look forward to it.

when ive got my head round this ill post my effort :)

[Seven]

ok i need to ask this.. ill look like a wally but i need to ask :)

My knowledge of texturing is limited, im a modeler. I rarely texture my creations and rarely animate them. But i need to ask, i need to learn sometime. My texturing knowledge is limted to this. Ive made my model, the i uv it, paint in Photoshop and then put that on the difuse layer. I can use bump map, spec, reflection/refrac and opacity.

All i do is find the file and put it onto the material. Then onto the model. If it stretchs, i tweak it.

This might sound dumb but I am still confused about Material ID. Ive been looking in my manuals but they dont explain it.

From what ive gathered are material ID's the ability to apply for example more than one jpg to one material? So they both blend together ?

In your explanations you say attach the 2 spheres together then give them both a unique ID.. thats very confusing for me. I would give the two spheres different materials but ive gathered you can give 1 material several ID's, and that ID's can give much more impressive effects.

Anyone got a good web page which explains Material / Mat ID's in detail and maybe some exercises. Im disappointed in the manual, its not as good as it should be.

ive used the word confused far to much :)

Sev

[gnarlycranium]

Material ID isn't too complicated actually. The individual faces of an object all have ID numbers-- if you put Edit Mesh on an object, go to Polygon or Element sub-object level, and scroll down to Surface Properties, you'll see where these numbers are picked, right above the smoothing groups section. Just select some faces or the Element you want to change, and type a number into the ID box. This number will correspond to the slot in a Multi/Sub-Object Material. So... what you'd do is make a new Multi/Sub-Object Material, give it 2 slots, drag and drop your eye material and cornea material into each one... and then go to your eyeball, pick the inner Element, type in 1, then pick the outer one, and type in 2. That make sense?

I'm obsessed with eyeballs myself, I'm constantly fiddling with trying to make better ones, but never really seem to get too far. Heh.

Gonzo, I tried that cornea material you posted up there... and all I got, from the anistropy, was weird loopy highlights. This puzzles me.

[Seven]

thanx alot Gnarly, i believe that does make sense. Ill give it a go later tonight (uni work now :( ) and see how i get along.

Im sure ill be asking more questions :)

[Gonzo The Great]

If you'd look at the numbers in the anisot. settings in pic I posted then yeah... it would look funny.

2 reasons:

a) I actually just did whatever in a about 5 seconds to show Seven where to go. I didn't have a model in the scene.

b) the anisot. orientiation is very fiddly and can only be taylored to a particular mesh at that particular time.

You have more control over the anisot. shader in either (A) Static Images and/or (B) Static Rigid models such as a car.

*You will get odd results when dealing with deformable surfaces - As general rule that I follow for any model, not just eye fluid, if the glossiness is set to Zero, for instance, having the two anisotropy settings above 60 is a little too hardcore. In other words - I pull back and keep it a little more round.

------------------------

This is what you should do if you need tears.....

The red and blue are the same object - but has a morph target from red to blue. To create flowing fluid - add a noise modifer that increases the closer it get to the blue target.

Sorry I don't have max on this machine.

I think we have a Winner for the Crapiest Image Post Award!

[Seven]

Gonzo thats fantastic.. you truely are an artist :)

Thanx for again more help...

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