2 simple roto functionality questions

Hey mocha community,


Two questions:


I’ve recently been trying to implement more usage of the attach tools to bind the various roto shapes in my work together. However I’ve come across a few problems I can’t figure out.

  1. If a layer has been feathered (had it’s edge expanded or retracted from the shape), the attach tool does not equalize the edge difference between the two points, resulting in issues/errors like this one (where the head and the neck shapes meet), where the feathering adds an extra “bar” between them when they don’t perfectly sync:

(1st linked image)


  1. If points on two separate roto splines/(shapes) have been attached, they cannot have there edges relaxed by grabbing a “uniform” spline tangent for the attachment, resulting in completely sharp connections between shapes in all attachment interactions:


(2nd/3rd linked image)




I feel like I’m missing something here, but I find it difficult to find the tool useful if both of these common necessities in roto are not supported by it.


Any help is appreciated,



Hi Taylor,

The workflow of connecting layers connects straight lines for seams, so you would not be able to curve that point, but you would be able to curve the points around the, The bar looks like a rendering error on our part. You might try overlapping shapes if you want the curves you’re looking for and more control over the feathering and overlap.

I will let Martin, our product manager, know about the draw error. What version of mocha are you using?


Sadly I cannot see the images. Can you try relinking?

http://imgur.com/a/JOJJO I think it got pasted in weird, I removed the formatting from the end.