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View Full Version : How To Model Veins Or Arteries



Ty Catt
02-25-2008, 11:19 AM
What is everyone's opinion about how to model veins or arteries?:help:

Some many different ways, different headaches for me.

Smooth shift vs. bevel a tube?

Sub-patching rendering issues to avoid?

It's the tiny off-shoots and branches that are killing me.
Just Boolean the branches out?

Luckily, I don't have any vein fly-thorugh scenarios to deal with (this time:) )

Thanks.

Ty

JeffrySG
02-25-2008, 04:55 PM
I think I would use a subd cylinder with about 5-8 sides. I wouldn't boolian out of it but rather use multi-shift or extender plus to extrude out of a section every so often... Also, take a look at Willams (or mine) pipe joints video. Mine is in my sig, his is at the sticky in the tips and tricks area.

Ty Catt
02-25-2008, 05:16 PM
Jeff,

Thanks for the tips!

I am only up to LW 7.5, and extender "plus" or multi shift may be not be in there, but you have pointed me on the right track.

And I'll definately give the tutorials a look too.

AND NICE PHOTOS ON YOUR HDR LINK!

THOSE ARE SHARP (and clever might I add).

WISH I KNEW HOW TO DO THAT!

All it needs is the Cloverfield monster tearing it up.

Thanks again,

Ty

JeffrySG
02-25-2008, 09:38 PM
Thanks Ty, let us know if you get stuck...

3D Kiwi
02-25-2008, 09:56 PM
If you are on version 7, try taz pipe, you should find it on flay.com.

you draw splines where you want the veins to be and run tazpipe, and it basicly extrudes geomerty down the splines for you. Then all you have to do it weld up were you want the veins to join.

art
02-25-2008, 10:12 PM
if everything else fails try my bezier bridge, but the joints still might be tricky.

Ty Catt
02-26-2008, 06:53 AM
Thanks, guys!

Taz Pipe isn't at Flay anymore. Did a search, can't find it anywhere. I'll keep trying.

I'll try Bezier Bridge, too.

Thanks, again.

Ty

art
02-26-2008, 07:25 AM
I have a copy of Taz Pipe. I hope it's ok to distribute it (its free anyway)

art
02-26-2008, 07:32 AM
The website seems to be gone but the download link still works(!). I found it on spinquad, but it's probably available somewhere on this forum as well:

http://www.steelronin.com/plugins/TAZ_Pipe_v2.4.zip

mattyb
02-26-2008, 08:06 AM
magic bevel can be handy for small capillary beds and smaller veins.

Ty Catt
02-26-2008, 08:12 AM
Thanks for the link Art, got it!

I'll try Magic Bevel, too, Matty.

I have to model the SMA (Superior Mesenteric Artery) which runs into the intestines for a jury. They actually loop back into themselves for the blood flow. Should be a hoot to create.:thumbsup:

I will post some images when I get there.

Thanks again, everyone.

Knowing this forum exists eases my stress ALOT!:)

Ty

Surrealist.
02-26-2008, 12:02 PM
On the magic bevel tool you can set it so the ends don't taper or taper very little. Use the scale setting.

William also has a video on it too.

But for something that has to curve around in an exact way, I might think about doing something curve-based if you can, then use the rail extrude. You can do this off of a poly that is part of an existing vein. Then clean up the geometry like in Jeff's video on the flanges where the veins connect so you have a smooth polyflow.

art
02-26-2008, 01:38 PM
I forgot to "advertise" another free script of mine, extrude+. Although it is not exacly finished, it quite functional and can help you with veins. Like other extrude tools it can extrude along a curve, but it also has a number of noise options that can help with getting a more ogranic look.

Ty Catt
02-27-2008, 02:43 PM
Hey guys,

Here's where I am thus far- didn't get as much time to work on it today as I had hoped.

Not really proud of it, just wanted everyone to see your advice in action.

So far using Taz to do the modeling. (Thanks again Art for plugin!)

I may change methods, just dry run first.

Subdivided tube (ala Jeff) would help with those nasty abrupt branches.

I am using a medical image as the background for guidance.

Once the tiny tendrils come into play, I will have to start working on all axis as they creep around the intenstine. Probably should have planned that first. That's my biggest problem with LW- what to do first!

Thanks again, more to come hopefully tomorrow.

Ty

3D Kiwi
02-27-2008, 03:02 PM
Looks good so far, Only thing i would say is to use a 4 sided extrusion with tazpipe. Other wise you mesh is going to be huge and welding all the points together when you join everything up will be a nightmear. (Depending on how much of it you are making)

I had to model the entrie cardio Vascular system when i first started here doing medical animations, Get ready for lots of coffee.

Also keep all splines that you use in another layer, you may need to go back and tweak them later on.

Here is a image of my CV system, I didnt model the heart and lucky didnt have to do any nerves.

Ty Catt
02-27-2008, 05:36 PM
Kiwi,

Thanks for the tips- I thought a low side count would make a poorly rendered curve. Should I increase the segment amount to compensate? Does that also help you weld 4 points to another four points almost anywhere by having lots of segments?

Hopefully I can apply your suggestion to the thinner veins tomorrow!

Your CV system is SWEET! EXCELLENT WORK!

Do you upload your work for sites like TurboSquid? If not, you should! Serious dough to be made there, my friend!

Thanks, again!

Ty

3D Kiwi
02-27-2008, 05:53 PM
The amount of detail in the model really depends on how you are going to use it, eg close up shots will need more and areas in the background need less even to the point of not haveing to weld certian areas. This model is used as a generic model for many different types of shots so i went to effort to weld everything up. Best thing for you it to do some tests and see what you can get away with.

My model has a poly count of around 72k including the heart unsubd, so you can see how fast the count can climb.

Do some test and post them if you like.

Ty Catt
02-27-2008, 06:05 PM
Kiwi,

Good deal.

I appreciate the pointers.

Now here's another question (kinda related)...

Someone suggested watching the William Vaugn tutorials too and I was wondering... is there a trick to watching the William tutorials?

I am embarrassed enough not knowing they existed until a a few weeks ago:o , but on two seperate computers now I have clicked on the movie link, it tries to download, and then I get the QT logo with a question mark through it.

Is there something else I am missing?

Thanks again,

Ty

3D Kiwi
02-27-2008, 06:50 PM
im guessing you will need the latest quicktime codec, i just downloaded them from the ftp site to my hdd and they worked fine.

mattyb
02-27-2008, 07:20 PM
Another huge advantage of saving your the splines that you use to create your vasculature is that you can use them as paths if you need to show a something like a drug moving through a vessel or for a catheter placement.