How to keep subitem straight when using ffd


i want to keep every floor not changed when i use ffd for the whole group,

but when i use ffd, every floor is not keep straight anymore


Not really sure what you’re asking, what you’re trying to accomplish, but what I’m seeing is how FFD is supposed to work.

If there are certain vertices you want to stand still, you’ll have to make a selection of the ones you want the FFD to deform in an EditMesh or EditPoly which is lower in the modifier stack than the FFD, keeping the vertices which you want staying in place out of the selection. Then it should probably work the way you’d like.