Maya Extrusion Paths - Able to Shrink after Growth?

[Anonymous]

Hi All,

I have a question regarding an extruded path along a curve.
I know there is the option within the sub-curve to have geometry/nurbs extrude along the path until the end.

But, once it reaches that end point and the geometry is fully visible, is there a way to have the start of the path "follow" and shrink at the end--eventually disappearing?

There's a function within After Effects called "Trim Paths", but I haven't been able to find a similar solution in Maya yet.

Thanks for any insight,

-Olsen

[stephenkmann · Accepted solution]

if you are talking about 

Surfaces -> extrude   with Partial turned on. 

 you can animate the subCurve min max 

to have it grow along the curve, animate the subCurve Max from 0 to 1 

to have the tail follow along animate the subCurve Min from 0 to 1 

hth

-=s

[Anonymous]

I attempted! Thank you--Unfortunately it doesn't seem to work out that way.

It looks like when I do that, the line gets crazy and doesn't follow the path; or doesn't even "srhink" at all.

I've attached an example:

**I realize it says Subcurve82 (I have many throughout my scene).

Notice when I change the option, regardless of the decimal place, that the beginning piece doesn't move. If the Min is set to the full '1.0' the disappears, but keying '0.0 - 1.0' doesn't follow the curvature. 

[stephenkmann · Accepted solution]

It all depends on which settings you are using and where the profile curve is and how it is aligned to the path. 

I made a video tutorial that might help you 

https://youtu.be/_1LShiYfBcc

[Anonymous]

Hi Stephen,

Thanks so much for the *surprisingly* long explanation and different examples: I appreciate it!
It's a shame that the 'double-sided' render option is kind-of a forced solution. Do you think there's a way to take the orientation of the nurb, and have it match the initial curve point 1:1? Perhaps an orient constrain in some way?

I'll futz around and see if this makes things easier.

Thanks in advance

-Olsen

[stephenkmann]

I wish, but curves have no normals.

I didn't go into it, but I usually make an up vector curve and then use that to aim the motion paths. 

I've made scripted fixes to this. but I haven't found an ideal solution in native Maya. 

another think you might look into is the curveWarp deformer. 

It has it's own host of issues. but might get you what you want. 

you can animated the "lengthScale" to grow along the curve, and the "offset" to slide along it. (similar to splineIK)