Compute and Redraw Lag

[dreidrage]

OK, so I am pretty sure this going to touch on the whole node vs command issue.  Here is the issue.
I've created a node
-this node updates other nodes by changing their transform matrix based on another object (ref object) within the compute call

it works almost perfectly,  whenever I translate the ref, the nodes update, whenever I change frames the nodes update

BUT  if I scrub the timeline or playblast and the ref object is animated there is a lag until I let go of the mouse and I've also notice this happens (very very subtly) if I rotate the ref object (not with translate) until I let go of the mouse.

Why would everything update properly except those two things and only until I let go of the mouse?  Is it possible that setting the value of the matrix plug of an object doesn't kick off it's own compute/draw call? 

As for the whole node vs command thing, if we're going to go into that. I chose a node because I am shooting for something that behaves more like a constraint.

Any help would be appreciated.

[joojaa]

Why would everything update properly except those two things and only until I let go of the mouse?

Yes well maya supresses most event calls outside normal scope. So unless your attribute affects netwroks are spot on this would happen. Also matrix most inputs/outputs are caches, so tey may or maya not be defeerred, you should really use the same kind of translate rotate inputs s normal translates/constraints do. See the decompose matrix example in the devkit for how to do this. As this is safer and better even tough tyhe matrix may seem right thing to do.

As for the whole node vs command thing,

If your using the api you dont want to make a command.

[dreidrage]

Thanks joojaa, that would definitely explain it and I'll check out the decompose example and get back. 

[dreidrage]

Actually,  I don't see the decomposeMatrix source files.  Just the compiled mll's, not in any devkit back to 8.0.  Anybody have this code or know where it should be?

[joojaa]

Upgrade your maya. It is also impossible to make fully functional contraints in mayas piror to 2008 releases.

But i do think bateman has a utline on how to do this. Nothing magic it is part of how the transform gets done. You can find it in the manual.