//IMPORTANT Time.fixedTime must match the timestep being used here.
public static List <UnityEngine.Vector3> SimulateBall(BRigidBody ballRb, UnityEngine.Vector3 ballThrowForce, int numberOfSimulationSteps, bool reverseOrder)
{
var ballPositions = new List <UnityEngine.Vector3>(numberOfSimulationSteps);
//Create a World
Debug.Log("Initialize physics");
CollisionConfiguration CollisionConf;
CollisionDispatcher Dispatcher;
BroadphaseInterface Broadphase;
CollisionWorld cw;
ConstraintSolver Solver;
BulletSharp.SoftBody.SoftBodyWorldInfo softBodyWorldInfo;
//This should create a copy of the BPhysicsWorld with the same settings
BPhysicsWorld bw = BPhysicsWorld.Get();
bw.CreatePhysicsWorld(out cw, out CollisionConf, out Dispatcher, out Broadphase, out Solver, out softBodyWorldInfo);
World = (DiscreteDynamicsWorld)cw;
//Copy all existing rigidbodies in scene
// IMPORTANT rigidbodies must be added to the offline world in the same order that they are in the source world
// this is because collisions must be resolved in the same order for the sim to be deterministic
DiscreteDynamicsWorld sourceWorld = (DiscreteDynamicsWorld)bw.world;
BulletSharp.RigidBody bulletBallRb = null;
BulletSharp.Math.Matrix mm = BulletSharp.Math.Matrix.Identity;
for (int i = 0; i < sourceWorld.NumCollisionObjects; i++)
{
CollisionObject co = sourceWorld.CollisionObjectArray[i];
if (co != null && co.UserObject is BRigidBody)
{
BRigidBody rb = (BRigidBody)co.UserObject;
float mass = rb.isDynamic() ? rb.mass : 0f;
BCollisionShape existingShape = rb.GetComponent <BCollisionShape>();
CollisionShape shape = null;
if (existingShape is BSphereShape)
{
shape = ((BSphereShape)existingShape).CopyCollisionShape();
}
else if (existingShape is BBoxShape)
{
shape = ((BBoxShape)existingShape).CopyCollisionShape();
}
RigidBody bulletRB = null;
BulletSharp.Math.Vector3 localInertia = new BulletSharp.Math.Vector3();
rb.CreateOrConfigureRigidBody(ref bulletRB, ref localInertia, shape, null);
BulletSharp.Math.Vector3 pos = rb.GetCollisionObject().WorldTransform.Origin;
BulletSharp.Math.Quaternion rot = rb.GetCollisionObject().WorldTransform.GetOrientation();
BulletSharp.Math.Matrix.AffineTransformation(1f, ref rot, ref pos, out mm);
bulletRB.WorldTransform = mm;
World.AddRigidBody(bulletRB, rb.groupsIBelongTo, rb.collisionMask);
if (rb == ballRb)
{
bulletBallRb = bulletRB;
bulletRB.ApplyCentralImpulse(ballThrowForce.ToBullet());
}
}
}
//Step the simulation numberOfSimulationSteps times
for (int i = 0; i < numberOfSimulationSteps; i++)
{
int numSteps = World.StepSimulation(1f / 60f, 10, 1f / 60f);
ballPositions.Add(bulletBallRb.WorldTransform.Origin.ToUnity());
}
UnityEngine.Debug.Log("ExitPhysics");
if (World != null)
{
//remove/dispose constraints
int i;
for (i = World.NumConstraints - 1; i >= 0; i--)
{
TypedConstraint constraint = World.GetConstraint(i);
World.RemoveConstraint(constraint);
constraint.Dispose();
}
//remove the rigidbodies from the dynamics world and delete them
for (i = World.NumCollisionObjects - 1; i >= 0; i--)
{
CollisionObject obj = World.CollisionObjectArray[i];
RigidBody body = obj as RigidBody;
if (body != null && body.MotionState != null)
{
body.MotionState.Dispose();
}
World.RemoveCollisionObject(obj);
obj.Dispose();
}
World.Dispose();
Broadphase.Dispose();
Dispatcher.Dispose();
CollisionConf.Dispose();
}
if (Broadphase != null)
{
Broadphase.Dispose();
}
if (Dispatcher != null)
{
Dispatcher.Dispose();
}
if (CollisionConf != null)
{
CollisionConf.Dispose();
}
return(ballPositions);
}