btRaycastVehicle and btKinematicCharacterController are derived from btActionInterface now.
Some cosmetic cleanup: changed sourceforce/sf.net url to bulletphysics.com.
Please see HfFluidDemo.cpp for examples of how to use the height field fluid along with buoyant collision shapes.
The implementation is still lacking in my ways:
1) Need to complete more collision algorithms for buoyant collision shapes
2) Support compound buoyant shapes
3) The buoyancy model isn't that great
4) Fluid volume can be lost over time
erwin.coumans
john.mccutchan