View Full Version : CURVE CONFORM with rotation

11-28-2006, 10:41 AM
I am trying to get a helix to conform to the shape of a curve and rotate while maintaining the shape of the curve. Somewhat like a piece of tubing being placed on a piece wire with a couple of gentle curves and then twisting the tubing so it rotates around the wire while maintaining the shape of the wire.

The deformation Curve Conform works great for getting the helix to assume the shape of the curve but I can't get it rotate in place and maintain the shape and postion of the curve.

Any suggestions would be greatly appreciated.

11-28-2006, 12:02 PM
Try DStorms Trailer plugin

12-04-2006, 02:41 PM
I tried "trailer" but in order to get the effect I want the chain has to so long that the number of polys becomes so large that my machine hangs

12-04-2006, 03:07 PM
Havent had that happen. What is it that youre animating?

12-05-2006, 07:28 AM
I am trying to bend a a DNA chain, a double helix with cross connecting bars much like a twisted ladder with rungs, and have it rotate while maintaining the shape of the bend.

The original chain was created with the Y axis as the verticle center. This is the axis of rotation for the aninmation.

It's almost like a very moving slow roller coaster with a cork screw turn except the path is through the center of each car not under the cars wheels. Or possibly a like socket wrench with a universal joint between the wrench and socket.

The total time is about 10 seconds, so if I make a chain long enough so "trailer" provides 10 seconds of movement through the cameras field of vision, the chain it seems is too long for my machine to handle.

12-06-2006, 05:18 AM
So basicallyl you need the DNA chain to start straight and twist or already be twisted but moving up and spinning/twisting or does it need to twist along a specific path?

12-07-2006, 09:54 AM
Think of the chain starting out as a tube or drinking straw standing straight up. The "Y" axis being the axis of spin or rotation is through the verticle center of the straw. Easy to do as long as the chain is straight.

The chain would then be "twisted" or conformed to a path.

Once the curved shape is achieved, the chain would need to rotate on the same "Y" axis but that axis is now bent along the path.

So far, once I get the shape the way I want, when I rotate the chain, the chain AND the path rotate as one - where what I am looking for is the chain to rotate but be constrained to a fixed path or shape.

I think this may be one of those things I can see in my head but may not be able to articulate cleary.

12-07-2006, 02:58 PM
Can you post a pic of the geometry youre using for the DNA chain?

12-08-2006, 09:09 AM
Here is a jpg of the chain and lwo of the object and path.

12-08-2006, 05:16 PM
Try using the trailer plugin but turn off subpatches on your object first.
It works for me. :)

12-12-2006, 01:26 PM
I have tried Trailer and it does a great job of moving the chain along the path but thats not what I am trying to do.

I am not trying to make the chain start at point A and go to point B along a fixed path.

I am trying to get one end of the chain to start and remain at one end of the path and the other end of the chain start and remain at the other end of the path. The path does not move nor the chain move along the path.

Imagine the path is a length of wire bent in an "S" shape. Then take a tube and slide it onto the wire where is covers the entire length of the wire. Now if you rotate or twist the tube at one end - without changing the shape or position of the wire - the tube rotates ot twists around the path created by the wire while still conforming to the shape of the wire or path.

I could make this work by creating 360 chains, in modler, with each chain rotated 1 degree on the Y axis more than the previous chain. Then by loading them one at a time onto the layout stage, apply the curve conform and render the images one at a time, but this would be much too time consuming.

I guess I can't explain clearly the effect I'm needing.

Thanks for your suggestions and patience.

12-13-2006, 11:42 AM
Attached is a 30 frame sample of what I am trying to achieve without having to model and stage hundreds of times.

12-13-2006, 11:45 AM
My bad.

12-13-2006, 03:40 PM
I see, What you want is the PLG Curve to Bone plugin. Its basically a free spline IK tool that will do exactly what you want.

12-14-2006, 11:38 AM
Thanks -

I downloaded the plug-in, and the scene that was included looks like it will work, if I can just figure out the controls.

How to create and link Cont, cont2, cont3 and goal to the virtual spline.

The encluded "manual" appears to discuss how the controls function but not how they are created and linked and linked to the bones.

12-14-2006, 08:30 PM
Try this scene.

12-19-2006, 09:25 AM
Thanks for your help and patients, the scene you sent me got me going in the right direction.

12-19-2006, 09:38 AM
Cool, hope it works out. From what I can see it should :)