Pharan wroteFFD? FFD doesn't make things rotate. It can't. It doesn't recognize the mesh as a whole, it just interpolates a line between positions per vertex.
This is expected behavior. It's how FFD works in other programs too.
If you need a set of vertices to rotate, use Weights.
As you can see in the image, once you scrub the timeline, the verts DO rotate just like they should, so I'm not sure what you mean by it can't. Sometimes it is more practical to rotate a small group of verts in mesh animation to get the shape you want than to create special bones/weighting for that one instance.
I came up a with a way to reproduce it:
- create a mesh with a bunch of verts (hitting 'generate' in the mesh edit menu a bunch of times is good)
- create an animation, key the mesh on 2 frames
- on the 2nd frame select all the verts and move them to the side
- select nothing
- on the 1st frame select some of the verts
- go to the second frame (using a hotkey) and rotate the verts (they should not be rotating in a nice way)
- undo the rotation
- click the timeline on the dopesheet
- rotate them now and it works.
new edit: added 'using a hotkey' to step 6
new new edit: it used to say 'scrub the timeline', I changed it to click the timeline on the dopesheet, it seems all you have to do is click it.
