i need to move box2d body in some kind of path this paths are drawn at the time of development and they are most probably like ellipse,arc, combination of arcs so any good way to move them in that way without setting their position manually
You should use it, when you need precise collisions and correct behavior of the orbiting bodies after collision
2) Or simply tween (or update position on enter frame) to fly around some object
with angle A and radius R, you can calculate the x and y position like this: x = R*cosA y = R*sinA
So you can for example, update A (angle) in each enter frame and calculate and set positions of the rotating object
This should be used for static rotations (without much of orbit changes) with static bodies and without precise collisions (for example with collisions with sensors) and when you don't need the body to behave properly after collision (jump back or change orbit, etc)
Comments
1) More complicated one is to simulate orbiting:
http://box2d.org/forum/viewtopic.php?f=3&t=9344
http://www.emanueleferonato.com/2012/03/28/simulate-radial-gravity-also-know-as-planet-gravity-with-box2d-as-seen-on-angry-birds-space/
You should use it, when you need precise collisions and correct behavior of the orbiting bodies after collision
2) Or simply tween (or update position on enter frame) to fly around some object
with angle A and radius R, you can calculate the x and y position like this:
x = R*cosA
y = R*sinA
So you can for example, update A (angle) in each enter frame and calculate and set positions of the rotating object
This should be used for static rotations (without much of orbit changes) with static bodies and without precise collisions (for example with collisions with sensors) and when you don't need the body to behave properly after collision (jump back or change orbit, etc)