Why do I have multiple `mesh` nodes per object?

[naughty]

Um, not sure if this is the right forum for this question but here goes...

You know in Maya, an ordinary polygon object should consist of a TRANSFORM node and below that a single SHAPE node... right?
Well I've got a couple of objects in my scene that have THREE shape nodes? The second two contain NO geometry but in the Attr Editor they appear to be regular shape nodes (i.e. they have mesh shape parameters > Tessellation Attributes, Mesh Component Display, Disp. Map, Render Stats, etc..)

In the HyperShade they show up when I graph the object but they are light grey (whereas the normal object nodes are DARK grey) and they have NO connection lines coming IN or going OUT.

I can select them and delete them and my scene is totally unaffected by their removal yet Optimize scene ignores them...

anyone know what they are?, how I created them? or how I get rid of them? (automatically)
So far, the only way I've found to distinguish them is that the [b]filterExpand -sm 12[/b] (polygon) command doesn't return their names...

:nathaN

[jeffd]

I am not sure what causes this, but I know that it is possible. Maya doesn't stop you from simply parenting a shape node to a transform that already has a shape node. I came upon this once when working on a script. It made me real nervous as I figured it would cause Maya to blow up at some point.

--JeffD

[campbell]

I might be off track here, but id say they are simply mesh duplicates created when needed for doing various historisised operations (kept under the same transform when meaningful). They probably stick around on a scene opt. because they are attached to a transform: being used. They may be hanging about because of partial history deletion - and have no effect when deleted 'cause, like you said, they no longer pipe/contribute to any other nodes. Such nodes can be the 'intermediates' of deformers (display opt in Deformers). If they are not part of deformer pipe, you can flip the 'intermediate' flag off in their shape node to display them (or a show/visib might surfice). Intermediates are treated like invisible/hidden nodes ..so in HyperG you can turn off disp. invisible. You sure they have no geometry assoc w them? Do, say, a polyEvaluate -v on these nodes? Or just display them. Can you have a mesh node w/o components (need at least a face)? You can for nurbs (tho they are considered 'invalid') ...Perhaps some ops use shape nodes for their non-geometric properties and hence cull the geom...?

Dunno, try building a simple scene and watching where shite goes, and see how you can make it linger.

c.

[naughty]

This problem is actually something two collegues have managed to create. I tried to recreate it myself on some of my scenes but I don't seem to be able to and they've no idea how they did it, although nearly all their scenes feature this oddity.

I think these nodes are definitely something to do with 'empty' history states though because occasionally objects with weighting or other animation stuff on them have one of two connections to these nodes.

I'll just have to keep an eye out, I've managed to write a script that removes any unwanted ones so it's not so bad, they were just giving me a really weird error in another script that was supposed to detect transform nodes without shapes ("empty groups")

:nathaN