Amazing disappearing brain

Hello,

I have a mysterious disappearing object. The blend below has the beginnings of a brain shape which is not showing up in the Blender internal renderer. It is showing up in YafRay, and as you can see other objects in the same layer are showing up. Furthermore it’s not simply not showing up, but it’s negating whatever is behind it… that is, if placed in front of another object, you get a brain-shaped area of background blue where the other object ought to be. I’ve had this happening in both 2.37 and 2.4.

http://s25.yousendit.com/d.aspx?id=1M75I6IKB7JEX33NWBD8H7NN4Z

While I’m in here, by the way, I may as well ask if anybody has any good suggestions for a way to model the wrinkles on the brain surface… I have a few ideas but no very good ones…

Thanks for any responses,

Tony

On your brain material in the mirror-transp tab you have the “env” button depressed. Unselect it. You could use displacement mapping for the wrinkles but they would probably look best by actually modelling them.

GreyBeard

Thanks!

Hi,

I’m back. The brain is no longer disappearing, but now I’m looking for words of wisdom on modeling. The more I get into this, the more complicated it becomes.

I quickly abandoned using textures (although there were some near misses there) and went with GrayBeard’s advice to model the surface of the brain directly. But I’ve been having trouble coming up with a good strategy. Modeling the wrinkles by hand, wrinkle at a time, using the face knife tool, was not working at all. So I tried a tack that seems promising, using the bezier curve (in poly mode) to map out the general shape of the wrinkled up tubelike shapes, then fattening that line up, beveling it, turning it into a mesh, and subsurfacing it. It’s a really great brain surface, actually. The problem is, it’s more or less on a plane, and if I try to force it to fit onto a sphere (or, y’know, brain shape), it becomes distorted. The other problem, but this may be unavoidable, is that it has a huge number of vertices, which is causing serious trouble to my processor.

One possible next step will be to try to model the tubules (or whatever they’re called) using the poly curve directly in 3-D space. But what I have in mind would involve turning the whole space around every time I extrude a line segment, and doing it by hand I’m sure that the surface of the brain itself won’t wind up being very even.

So, if anybody has any ideas, I’d love to hear them!
T

By “force it into a sphere” by the way, I meant that I tried a couple of ways, mostly involving some form of proportional edit with spherical dropoff. I haven’t tried warp, but that seems to only work for cylindrical shaping, unless I’m mistaken.

I would model the basic shape of the brain and then use Sculptmesh for the ridges:

https://blenderartists.org/forum/viewtopic.php?t=31732

%<

Wow, thanks. That looks like a really cool tool!.. also it gives me a good reason to start delving into the world of using scripts…

Hi,

Well, I have tried using the Sculpt Mesh script, but it doesn’t seem to be happening for me. I tried both the 23 and the 25 versions, also in both blender 2.37 and 2.4, and I’ve got both Python 2.3 and 2.4 installed, and both my Blenders are finding them fine.

When I run the script in 3.7, I get no complaints, but LMB on the object doesn’t change anything, simply alters the shading of the object for the time the button is held down and the word “cube” in the lower lefthand corner changes to “mesh” and back. Using scupt mesh 25 in blender 2.4 gives me the following runtime error when I click LMB.

Traceback (most recent call last):
File “<string>”, line 852, in ?
File “<string>”, line 776, in main
File “<string>”, line 387, in displace_vertices
RuntimeError: uv list is empty

Any suggestions as to what I may be missing or any possible workarounds would be appreciated. I actually do use a Wacom tablet, so I also downloaded PyTablet, which doesn’t seem to be causing any problems… But the behavior of the script is the same with or without PyTablet installed.

Thanks,

Tony

Are you sure this error is from SculptMesh (you were maybe using UVDisplacement script before and this message is left in the console)?

The reason I ask is line 387 says “workingMesh.Update (1)”

and sculptmesh shouldn’t care whether you have UV’s assigned or not.

%<

Are you sure this error is from SculptMesh (you were maybe using UVDisplacement script before and this message is left in the console)?

The reason I ask is line 387 says “workingMesh.Update (1)”

and sculptmesh shouldn’t care whether you have UV’s assigned or not.

I think that the error is from SculptMesh. I haven’t knowingly called any other scripts, for one thing, and for the other thing, it seems that line 387 is actually the last line of the definition of the displace_vertices function, so that all makes sense and points to the error being from SculptMesh.

I actually think I’m going to repost this question under it’s own thread to keep the topics straight.

T

[/quote]

Hi,

I didn’t see this topic previously,

do you have the blend and I’d be happy to check on it,

thanks,

LetterRip