# Super Monkey Ball / Neverball level rotation system

Im making a sort of remake of Super Monkey Ball 2 (Gamecube) / Neverball (PC) is simillar too, but i have already encountred problems:

In SMB (Super Monkey Ball 2) or Neverball, you dont move the ball, you move all the level, and the ball just use gravity for roll.

But in SMB / Neverball, the Level rotation pivot point is allways placed on bottom of the ball, for get allways the same rotation force, and for not get catapulted.

This is my problem, i have already vertex parented an empty to my ball, but i dont know how to make my empty the rotation pivot for the Level (dont forget, the empty may move with the ball, but the level can only rotate):

I give you some pictures:

Here is my main scene, the level is actually just a plane for testing.

You can see the vertex parented empty at bottom of the ball (the empty is vertex parented to the center of the ball).

In the game, if my ball is here, the level must rotate like this:

If you have a idea for making this (a sort of rotation-only parent...) i will be verry happy.

• Will this Python Constraint do it?: blender.org/api/blender_python_api_2_76_9/bge.constraints.html . I would like to see this working as well. – Coby Randal Jan 30 '16 at 20:44
• Found a live thread on this subject here: blenderartists.org/forum/… Definitely involves using Python and math utilities to pull it off, but we are closer to a decent answer than ever. – Coby Randal Jan 30 '16 at 21:46
• Thank for your help, but the rotation angle must be defined by the joystick return value, in real time. – Hack0re Feb 1 '16 at 0:33
• I actually trying to do the same in ue4, but seem to be hard as well. – Hack0re Feb 1 '16 at 0:35
• Ha! Cool. I downloaded UE4 and played some demos on it yesterday. For the joy stick input, I imagine it moving an empty that sits under the ball, but rotates about the ball's center. The ground level will have to rotate with that empty to some degree, and your camera will also be affecting the joystick rotation right? I know this can be done, but it has to be properly defined with pseudo code and then made into Python with the right math libs etc. – Coby Randal Feb 1 '16 at 4:20