Procedural texture for irises

[ReneAlex]

I found this but i dont remember where...

it cant be useful and easy to modify.

its a photoshop action

[dvornik]

Thanks.
I think I know where:

http://www.terryf.dial.pipex.com/htm/iris.shtml

It's would speed things up, but It's still a bitmap, though. I'm trying to come up with some kind of radial gradient ramp with noise or something along those lines.

[ReneAlex]

checkout the Daniel Martinez Lara - pepeland homepage - (http://www.3dluvr.com/pepeland/) here are some examples of procedurals iris... dl the free model of anibal and analyze the mat of the eyes...

I hope this help you out!

:beer:

[dvornik]

Look at the eyes "Unknown" has done in Maya:
http://www.cgtalk.com/showthread.php?s=&threadid=12472&perpage=15&highlight=eyes%20tutorial&pagenumber=5

On the next page there are eyes by MDC with the description of the shader in Maya.

Some max eyes that are not as good are on page 8 of that topic. So far I can only get some regular noise, without radial streaks, like at pepeland.

OK, a simpler question:

How do I stretch fractal noise radially?

[dvornik]

Ok, a strange problem. I'm mapping a cone or a cone-shaped polys by noise map. The UV map is a cilinder as you can see. Looks good in viewport. When I render it it comes out with a totally different UV coordinates. Why is that? A bitmap or even checker maps properly on the same object. I unwrapped it to check - looks OK.

[Chris]

its probably because when viewing a procedural in the viewport Max renders the procedural as a bitmap & applies it to the object temporarily, so you see the texture 'stretching' to give the iris effect. At rendertime however it renders as a true procedural, which is a 3D texture, so you dont get the stretching, the texture goes 'through' the object...

[dvornik]

I guess you're right. I thought I was close. Damn... There's gotta be a way.

Well, I suppose that's why max eyes didn't look so good in that discussion - he just created the gradient ramp manually - you could probably do a better and faster job in Photoshop.

[Chris]

yeah sucks huh? The one time texture stretching would have been quite good, & it doesnt stretch! Damn contrary programs... :D

[ReneAlex]

take a look to this max file...

maybe someone find a way to strech it...

[dvornik]

Yeah, I was playing around with your file. What I've done is just mapped with radial gradient ramp and turbulent noise (no mask). Made the cone really long so the texture stretched. Collapsed the stack. Scaled the outer edge really large and flattened. Does the texture look stretched?

[Chris]

dosnt look stretched to me, sorry, :(

[dvornik]

Bummer.

[dvornik]

Hah! I guess there are just some idiosyncrasies in the program. If I convert a circle to polys and make more edges inside, then planar map, unwrap and scale circes up in edit UVW map - it works. Actually works with a cone as well. I don't know why I got stuck.

There was a bug report on discreet support that included a file that attracted my attention. It included the first two squares.

Now, any suggestions how to turn it into an iris?

[dvornik]

Oh crap, doesn't work in subobject. There's something wrong with how I use mapping modifiers.

[dvornik]

It happens to be easy in Maya. I don't even know Maya but could complete the following tutorial:

http://www.3dlinks.com/tutorials/maya/maya_tutorials.cfm?tutorial=EyeBall

Can I import eyeballs from maya to max? I guess not with procedural textures.

[MasterZap]

There was an eyes thread before

but I suggest using a CONE PRIMITIVE as your iris. Make sure "mapping coordinates" is on. Then add an edit-mesh modifier on top of it and delete the bottom surface of the cone. Make the material 2-sided. Show the underside of the cone.
Map black to the top face of the cone, and your iris material to the sides.

Thus by animating the cones top radius you dilate the iris.

To get the texture stretched, make sure it is mapped in "Explicit map coordinates" and then stretch it way on Y by setting tiling on Y to like "0.05" or something.

Something like this

[dvornik]

Thanks a lot, I'll try it when I get to my computer. So you leave it a cone? Cause I was able to map a cone, but then I tried to connect it to the rest of the eye and the mapping gets easily lost. Kind of resets to non-stretched. On your eyes the transition from the iris to the white part looks very smooth. Do you just align the parts?

I reffered to that thread in my first post. I've seen your posts in there, that's why I started trying to replicate the texture in max.

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