i want to create plant wich will have interaction with player by physics(i mean for example character is moving in forest and plants are interactive physiclly with character when it collide)
i just dont know how to exacly do it. when i will add physics globally then plant will interact with root, but i need to root stay in one place.
and propably i will need add skeleton to it yes?
The BombControl in the bullet tests does something similar, “influencing things around it”. Maybe it can give you some ideas.
My attempt would be rigging a tree model and stuff… and then use it as some wierd kind of ragdoll… ^^
Ah, if by “plant” you mean not just one plant but whole vegetation you will probably not get far with real physics. Few games do that, most just have some fancy grass shader that gets some input on where to move the grass.
Probably you don’t want full on physics but just detect motion near the plant and bend the plant in the opposite direction. Just place some ghost physics object in the grass location and then sum the inputs of all objects around it and get an opposite vector to shift the grass by
i just never used more then simple physics for a ball 
ok so ghost physics is the key for solution. Tnx for help i will look later into it 