There's a single surface mesh manipulation library in the archives you could try but ......
As you mention - each body part has one texture & therefore one surface, to make single surface manipulation possible you'd have to make a larger texture with all the pieces in one and re-do all the uv's for each body part.
Even then, you would have to manipulate all the vertices a fair bit to achieve the same effect and this is sloooooow. It would probably be much worse in terms of speed than you already have and not worth the effort. I wouldn't recommend it.
I believe someone was working on a single surface animation library which was much faster than your standard animation techniques.. probably in the showcase but not released as yet.
Sorry I can't be of more help.
Stevie
As you mention - each body part has one texture & therefore one surface, to make single surface manipulation possible you'd have to make a larger texture with all the pieces in one and re-do all the uv's for each body part.
Even then, you would have to manipulate all the vertices a fair bit to achieve the same effect and this is sloooooow. It would probably be much worse in terms of speed than you already have and not worth the effort. I wouldn't recommend it.
I believe someone was working on a single surface animation library which was much faster than your standard animation techniques.. probably in the showcase but not released as yet.
Sorry I can't be of more help.
Stevie