ICE? I'm pretty sure there's either a sample scene or a tutorial floating around online on how to deform one mesh onto another.
It's a little late in the day for me to actually work this out, but basically, you'd have a highres mesh with an ICE tree getting position deltas (change from last frame to current frame), interpolated, from the corresponding locations on the low-res mesh. Might want to have matching UV's, but that might not be necessary. I guess really it's a cage deformer running in ICE, but without any kind of static weight binding from one mesh to the other. Or I suppose you could try the old cage deformer, but that's horrible -- slow and inflexible. Or extract a lot of curves from the low-res mesh, plot their shapes, and envelope the high-res to them, if you need something like your current workflow? Or maybe I'm not understanding how complex the geo is, but maybe you could cache the low-res simmed mesh, then extract the poly clusters that correspond to the different parts of the high-res clothing. Then either leave the extractions live or if it's too slow, cache them. Then apply however much subdivision and editing of the geo you need to the cached extracted meshes. Essentially leaving the modeling stack live on top of the low res sim. But that's getting kind of silly, I think. ;-) Ed
