Hi,
In a shocking turn of events, there is no documentation on the Edit SOP's 2nd input, for Reference Geometry. What does it do? It sounds like it might be useful, but naturally, I can't get it to do what I want. Perhaps it doesn't do what I want, hard to tell.
I'm trying to do blendshapes to fix problems with weighting on a character. I can't just use a regular Edit SOP because the edits are done in object space, not relative to the points being edited, so as the geometry deforms, the edits fly off into space and do bad things. Obviously, editing the geometry before the Deform SOP isn't useful since you can't see the problems there, and it also results in very very slow deformations since the incoming geometry is now changing.
I had hoped that the Reference input to the Edit SOP would solve this problem, but apparently not. Hard to tell, when there is no documention (
A simple case Box SOP, Transform SOP with $F in the Rotate Y field. On frame 1, apply an Edit SOP and pull a corner's points over to where you want them. Move to another frame and the points are God knows where…
Using the Reference input on the Edit to the pre-Transformed Box did exactly nothing that I can see.

Cheers,

Peter B

Reference geometry (Optional) When this input is connected, all edits take place relative to the difference between the geometry to edit and this geometry.

That's in the 8.1 help - maybe that's newly added, don't know. Please don't ask me to translate into english.

Cheers,

J.C.

Yeah, that's what I mean No actual documentation ) It _sounds_ like it does what I want, but doesn't seem to in practice…

Make sure you wire the reference input into the Edit SOP before you start modeling. (Supposedly this isn't required but I always do it anyway.) And when you do your final edit make sure you hit “Commit Transform/Peak Changes” at the bottom of the SOP to make sure that final edit was added to the gdiff.

Thanks Jim, glad I wasn't totally off base… I did have the 2nd input wired in before I started editing, perhaps it's the clicking the button that does it or something.

I'd go off on a rant about now, but I'm too tired and demoralized…

Cheers,

Peter B