Best way to model a brain?

[ThE_JacO]

it's one of those things where you'd be off 100 times better if you used a displacement map.
modeling a brain is a lot of boring grunt work if you want something that looks decent. Is displacement mapping not an option for some reason?

[CiaranM]

I took a med-viz class a while back, where this very topic was covered. The result, while not totally convincing, certainly looked like a brain and was relatively quick to construct.

The basic process was to model a base object that held the general shape of the brain organ. Perhaps a deformed nurbs sphere would do. You might want to model by halves and symmetrize later. Next, with surface snapping on, create a curve by drawing squiggly, curving lines across it's surface. It is important to study the patterns and undulations formed by the surface structures of a real brain - not just any squiggly lines will do! Finally you will extrude a circle along this long guide curve to produce a real surface form and lastly symmetrize.

You might also want to add some simple displacement deformations so that the surface does not appear too regular.

This technique was used in med-viz productions, which although not of cinematic quality, certainly converyed their message very clearly.

[mocaw]

Ditto and then some to the last two responses.

Well have fun with this trying to do it without a displacement map! It can be done, many have tortured them selfs with even more mind numbing (no pun intended) modeling.

If you have the money...take a serious look at ZB or MB. In ZB you could do it VERY quickly with just a base shape from XSI, some masking, inflating, and smoothing. Plus- if you want to use it in real time and you only have a diffuse and spec channel to work with baking out a cavity map from ZB will help you out once you go back into XSI and add the finishing touches before baking out your maps there. I think there is a curvature map that does something similar for XSI here:

http://www.claus-figuren.de/addons/curvaturemap.php

You could also use AO, but this will not behave the same way and give you the texture contol these other methods afford.

Even without ZB or MD displacement should be the first place you look- since unwrapping the base shape UVs should be fairly straight forward- and PS could then be used.

[toonafish]

unless you 'd like to model it yourself it might be cheaper to buy objects like that at a place like Turbosquid (http://www.turbosquid.com/Search/Index.cfm?FuseAction=ProcessSmartSearch&intMediaType=2&istSearchKey=brain&stgP=R39CZ2&grp=869&gclid=CJSrybyCg4wCFQpBQwodCQuF3A)

[nickmarshallvfx]

Wow thanks everyone, thats a great response! Actually, I dont have the option of buying a model, or using ZB or MB. We have to do the whole thing in XSI.
The only reason I didn't want to use a complicated texture was because I dont really have any experience at all with textures, and even my minimal knowledge of modeling beats my knowledge of texturing.

I think the most appealing option there sounds like the nurbs sphere and extruding along curves. I have some side views of brains to use as reference.
When I do that, do I have to get another primative sphere and extrude along the curve and then merge witht he original rough brain shape, or is there a way to actually extrude the original nurbs sphere along the curves?

Thanks for the help guys! Theres nothing better for a noob to have than a team of guys behind him to point him in the right direction!

Nick

[CiaranM]

No, you'll want to create a nurbs circle with the approximate width of the convolutions of the brain. Select it and create a polymesh using an extrusion operation along the guide curves (to be honest, if you don't plan to export the model or paint displacement maps, you might just want to keep the whole thing as a nurbs surface). Don't freeze your model or work in immediate mode until you are certain you are done. You'll be able to scale the original nurbs circle post-extrusion, and the whole extruded mesh will compensate. This could be useful for tweaking later.

You'll notice that you extrusions end abruptly, which is not good. To make a more natural appearance, you might move the end points of the guide curve towards the centre of the brain, so that the convolutions seem to emerge rather than just appear. Remember you can tweak the guide curve after extrusion until you are satisfied.

This will work fine for the cerebrum, but you'll probably want to model the cerebellum seperately.

Good luck!

[nickmarshallvfx]

Wow thanks Ciaran, that was remarkably iformative! I will make sure I post my results when I get done. Thanks so much, you've saved my life!

Nick

[barbapapa]

i did the next thing to get the general shape and then poly reduct and clean up.
There is this xsi addon thats is called save render mesh. I know that you already said that you dont know a lot about texturing, but im sure you would pick up in 15 minutes enough to get you started, and it would be faster than rather model the whole thing...
so this save render mesh addon , what allows you to do is save an obj of a displaced geometry. Just map the texture, plug the node on the lightmap slot of the material and render .You will have a 3d mesh of a brain (if you tweak the goemtry aproximation you will get diferent topology.. dont remember whichone i used.)
you will get a big mesh.. so use poly reduction tool and then just clean up... this was my aproach becasue i needed a toon brain asap.... you will see that the topology you ll get is not what you want... but i got nice results for what i wanted

hope it helps

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