Tangent Handles are missing

[sarida]

Why do some of the tangent handles disappear when I am editing vertices along creases in sculpt mode? In some cases, I can see all the tangent handles and in others, they disappear? What does control their visibility? I am attaching two screenshots, one has the tangent handles visible and in the other they are not. 

[jakefowler · Accepted solution]

Hi @sarida, and welcome to the forums!

You've hit upon one of the hidden subtleties in creases. We internally actually use two kinds of creases, depending on where the crease is in relation to star points and other geometry:

• "Long-fade creases" (aka NURBS-style creases) - we use these wherever we can. These kinds of creases actually extend two edges beyond the edges you select, but they give you nice smooth fade-outs, and they also allow you to control the tangent direction on either side.
• "Short-fade creases" (aka SubD-style creases) - in some situations we can't technically use long-fade creases (e.g. in regions near a star point). Here we use short-fade creases. These start and end precisely where you select the edges. The downsides are that their fade-outs aren't as aesthetically pleasing, and they don't allow you to control the tangent directions.

So if you have creases where tangent handles are not visible, they are most likely short-face creases, where the technology currently doesn't allow us to provide tangent direction control.

This blog post ("Crease Fade-outs and Yellow Regions" section) goes into some background about when long- and short-fade creases are used, and how to control some of this behavior (essentially, any crease that starts/ends in a yellow region will be a short-fade crease).

Hope this helps explain, but let us know if you had any further questions about this.

Thanks!

Jake

[TrippyLighting]

I'd have to say again, what a wonderfully detailed explanation. That blog post went right into my tips-&-tricks link collection.