1) By definition, gravity is an acceleration, not a velocity. So if you want something to fall at a constant speed you can't use gravity.
2) It's been a while since I've programmed Bullet but I believe there's a setPosition method for rigid bodies. I'm sure it exists, not sure of the exact function name or usage. If you want to move a plane, don't use a static plane, use the surface of a very large box.
Thanks for the reply.
1) If there's no gravity, then the object will not fall down right?
2) I'm using btConvexHullShape for the platform, and the mass is 0. The following code will not change the position of the rigidbody.
// code for creating rigidbody.
Isgl3dMotionState * motionState = new Isgl3dMotionState(node);
// Create a rigid body
btVector3 localInertia(0, 0, 0);
btRigidBody * rigidBody = new btRigidBody(mass, motionState, shape, localInertia);
// code for moving object.
tr.setOrigin(btVector3(btScalar(object.node.x), btScalar(object.node.y), btScalar(object.node.z)));
I've also set
when I created the rigidbody. Thanks!