Animating Geometry
 

OKay this is probably a really basic question but here goes. How do you animate vertices and faces if the structure of them changes during the course of the animation?

Example, animating a knife cutting through paper. If you don;t want the join in the the paper visible before hand i guess you need to split the vertices one at time to show split in the paper gradually progressing along the cut.

The doesn;t seem possible as when i alter the vertices or the faces the animation is lost.


Hope that makes sense, i must be missing something. How does everyone else deal with thi sort of problem?

Thanks in advance for any reponses

In maya you don't really animate the individual vertices for something like this, you can animate vertices using deformers like the 'lattice' or making 'blendshapes'.

For the example you gave with the paper, it would be best to line up the vert's, can snap one set of vert's to the other set, aslong as they share the same position in 3D space then you won't be able to see the gap between them.

Ask if you need some more help on the idea.

Chris

PS. I shall mock up something quickly like your demo to show the idea, will probably use a lattice or bend deformer.

Here's a little example I whipped up...

http://uk.youtube.com/watch?v=Qr3uhKokS5o

This was done using a bend deformer on a small poly plane with another larger plane next to it and below it.

Chris

thats great thanks thats exactly the effect it want. so the bit that bends is a seperate poly plane? how do you cover the initial seam?

EDIT: Sorry i managed to somehow only read your second post, that makes perfect sense thanks very much

okay i'm still having problems with this so hopefully someone can help

Here's my scene. I want to strip the selected sectin off gradually. I seperated the selection and placed it using snap to vertex.

http://www.cems.uwe.ac.uk/~rtann/May/workarea.jpg

in the render though, you can still see the join.


http://www.cems.uwe.ac.uk/~rtann/May/render.jpg


Can anyone advise what i'm missing?

Thanks again