Blending constraints

["Serguei Kalentchouk" <serguei.kalentchouk(at)ubisoft.com>]

Hi,

I am wondering if anyone can help me out here. Please bare with me here, when you apply a directional constraint to an object and leave up-vector option off. What you’d find is an ability to manipulate your object in one of the planes depending on which axis is constrained. Now if I go and apply another orientation constraint the object with this directional constraint what I find is that while it still respects the directional constraint the remaining plane of rotation left by lack of up-vector respects the orientation constraint. This gives an option for some interesting behaviour that I would like to replicate in a scripted op. But what I am struggling to figure out is how XSI performs the blending between the directional constraint and orientation one in this case.

In most cases, the blending between constraints is done via slerp of two quaternions but wouldn’t be in this case?

 

Any help would be appreciated.

 

Thanks.