Animate And Extrude With Nurbs/poly's

[jaidek]

Ok, so its been a while sinse I've tinkered with Maya. I recently jumped on a project where I need to animate a vein growing, kind of like a vine. I've done plenty of searching, and found to animate an extrude command you check the box for "Partial" for the curve. Here's my problem, the extrusion cap ends up being opened rather than closed (based on the circle curve), and there's no option for tapering it. Ideally, I'd like to have the same results as you would when you extrude the face of a polygon along a curve - taper, twist, and its closed - but there's no option for a partial curve in the polygon extrude options. So is there a way to animate a polygon extrude? Or a way to close,taper, and twist the end of nurbs curve extrude? I've tried re-sizing the points at the ends but when it animates it pops and goes nuts.

So other than using Paint FX, whats the best way to tackle this? Btw, I'm using Maya 6 but am in the process of getting 8.5 if that makes any difference.

thanks in advance!

[joojaa]

Well, here for your luck the gui does not reflect what is done underneath. The extrude soes not di the partial curve, the gui is doing it. So you could just look into the hypergraph to see what it connects and replicate the connection.

Ill give you a hint, it connects a sub curve node that then connects to the extrude

then theres the way i used here:

growmockup.mov you can get the fie if you want, its just a bit slow on feedback.

[jaidek]

That looks great! Are those polygons in your example or nurbs?

[gwelch]

Another methed is to model your vein at full length, straight, and move your pivot to the base. Next create a straight curve with the same length, then use the curve as a wire deformer for your vein, bend the wire into your end shape. Animate the Scale of the vein to grow. Repeat for branches. Using a leather 3D texture for the veins cells can give it a nice growing look when animated.

[jaidek]

QUOTE(gwelch @ 06/14/07, 09:30 AM) [snapback]268082[/snapback]
Another methed is to model your vein at full length, straight, and move your pivot to the base. Next create a straight curve with the same length, then use the curve as a wire deformer for your vein, bend the wire into your end shape. Animate the Scale of the vein to grow. Repeat for branches. Using a leather 3D texture for the veins cells can give it a nice growing look when animated.

Well when the curve is scaled down, wouldn't the the texture look scrunched together? I'd imagine the surface of the base vein when the growing vein is scaled down would look odd with all the detail thats being scaled down. The above video is the exact effect I'm looking for. Would your method produce the same results?

I'm at work, so I can't try it out until I get home.

Thanks again

[gwelch]

Could not see the video link, but to be clear, the idea is to scale the geometery (your poly or nurbs model), so it will "follow" along the wire deformer curve. Dont scale the wire curve. the curve is a path the growth will follow. The 3d leather texture, representing cells, does not get scaled either, so the geometery grows thru the texture, and looks like new cells are being added as the vein grows.

Scaling is a simple way of growing the vein along the wire. You could also make clusters to pull along the tip and middle thickness and not the base. A lattice can achieve the same effect, by animating the lattice points to "scale" the geometery in a more controlled manner than a simple scale.

The advantage is that you can get a nice tapper on your vein model first, then only worry about growing it with scale or lattice. Its also nice to be able to change your final grown veins position with the wire deformer curve CVs.

[ewigkase]

right now i am just learning the program Maya 8.5 I have learned to animate a extrude but when i try to animate a (polygon) to extrude along a path (trying to make it flow around some objects) it does not work. how do i do this? I don't know a my way around to much so help point me in the right direction please.

hope anyone can help this poor NOB

thanks