Hello, I want to make a boat game, but dont know how to start:
*How to make he float without let him sink.
*How to make movements for him, but without have problems as unwanted colisions at water surface.
I’m realy wanting to know that, if someone have a example, please send it, thanks;)
You could remove the gravity from him (small python script) and for the movements, you’ll have to animate them since there isn’t a realistic oceanic wave system built in into blender for the BGE, yet…
You could also try the “force field” constraint. (It’s one of the constraints available through the constraint actuator)
Why dont you use the material physics? See attached file.
The seabed plane has material physics that push up any dynamic object (like the cube) that are sensitive to them (set in the physics tab). The bounce can be controlled by damping or by using less spring force in the materials tab. The ‘water’ plane is set as a ghost and is transparent, like…er… water.
Anyway, I hope this answers your question.
Cheers
Paul
floating.blend (479 KB)
@CrazedQuetzal: Dude, that’s one actuator that literally blew me away! so useful! XD I’ve been thinking about how am i going to set up the swimming control for my character and the force field actuator is the thing. Spot on. Thank you! 
In other words i can confirm that the force field actuator works like a charm for this sort of a floating situation 