Cineversity

I’ve searched online but only find info on joining 2 splines, which is not what I’m looking to do.

Scenario
- I have a Spline that I’m using for a path (Spline Wrap).
- I’ve duplicated this and offset it with a null so I can use it as a Rail Spline.
- I then need to modify the shape of the Spline that I’m using for a path (Spline Wrap).

Question
- How can I have the shape of my Rail Spline update automatically as I change the shape of the Spline I’m using for a path. Is there a way to link the shape of two splines so they update simultaneously as one changes shape?

Usage
- I’m creating an animated ribbon via Spline Wrap. The ribbon twists as I change the Spline shape because the Rail Spline giving it proper orientation is not updating with it. I can duplicate the new spline and use it as a Rail Spline again but that’s something of a hassle.

-Pete

Hi Pete,

How would a MoSpline (Set to Spline) work for you. Perhaps an Instance Object instead? Both should work fine, but I do not have your file here.

(As a side note, I produce the rail spline often by letting a Null with a distance child Null running along the spline, while using a Tracer. On teh end of the timeline the Tracer has produced a nice rail, make edit and harvest teh new spline.)

All the best

Sassi

Thanks. Instance did the trick.

Another question… Is it possible to have the shape of a spline ease in or out? I have 2 keyframes of the shape of a spline via PLA. In the timeline I can see the keyframes when in key mode. But there is no data or curve in the F-Key Mode. Is it possible to apply an ease to the shape of a spline’s animation?

You’re welcome, Pete.

There are two way to do that. I recommend to use one or the other, of course you can mix it.

The first one is pretty simple, Bias, and allows for one adjustment not really for both sides. See image. As it is limited, even the fastest, I leave it out as an example (no scene attachment). To get both Keyframes work smoothly, one would need to set a new PLA Keyframe in the middle and have the first set to, e.g., 25% and the second then to -25%. Sounds a lot for extra work for a limited result.

The second way is a little bit more work and needs care. It is called the Time Track. You can have as many Time Tracks as you like, and you can apply each single one to many objects.
The idea is to have a F-Curve that can be set up from 0% to 100%. Zero % means here the previous keyframe value and 100% the next one. This “track” should be named wisely as otherwise the management of many of them will lead to problems. You can adjust this in the F-Curve manager, which allows for a very nice fine-tuning of the PLA effect.
BUT: if you move the PLA keys, do not forget to move the Time Track Keys as well.

As a side note, you can use as well the Pose Morph to animate Splines, and you have already an animate-able slider established with it.

All the best

Sassi

Image 1 : Bias, the native option in PLA
Image 2 : Time Track, see attachment. I called it here Time.peter, so it is easier to see what is needed.

Thanks so much. Time Track did the trick.

Perfect, thanks for the feedback, Pete!

Have a great start into your week!

Sassi