View Full Version : Xpresso - Problem Linking Splines Points to Mesh Points

06 June 2012, 01:51 PM
I am trying to do something extremely simple with Xpresso but can't seem to get it to work without 'lag' due to priorities or something.

Imagine an editable cylinder with a Bend Deformer on it. The Bend Deformer is keyframe animated between -90 and 90 degrees. I am trying to link the position of a spline point to a vertex on the cylinder using Point Nodes. (See attached).

Yes, I have "Use Deformed Points" checked on. The Xpression works, it just lags one frame behind. I have messed with the Priority setting ad nauseum and can't seem to get it to work properly with no lag.

I am done some pretty complicated animations in the past, syncing multiple points of medical sutures to other objects, but for some reason I just can't seem to get it to work now. Did the latest update bork something up, or am I just missing something simple?

Thanks in advance.

06 June 2012, 12:00 AM
It has behaved this way as far back as I can remember. The solution is to use a Point Cache tag.

06 June 2012, 12:26 PM
Thanks. Hmm I guess I've never really tried to link a spline point to a deformed object, it was always linking a spline point to an object axis (which works fine with no Point Cache).

What object do you put the Point Cache on, the spline or the mesh to which the spline point is linked?

06 June 2012, 01:54 PM
It's one of those things that doesn't work as expected.

The Point Cache tag goes on the Cylinder. Load the tag and click Store State, then Calculate. Remember to turn off the Bend deformer after point caching.

Change the Point Cache tag's Priority to Expression 0 or lower so that it's executed before XPresso.

06 June 2012, 02:02 PM
Ahhh. I neglected to change the priority of the Point Cache tag. Very helpful. Thanks!

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06 June 2012, 02:02 PM
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