C# Body.AddForce方法代码示例

        public void ApplyForce(Body body, float TickDelta)
        {
            Vec3 originalBoneDerivedPosition = bone.Parent.Position + bone.Parent.Rotation * originalBonePosition;
            Quat originalBoneDerivedRotation = bone.Parent.Rotation * originalBoneRotation;
            Vec3 pos = body.Position + body.Rotation * originalBoneDerivedPosition;
            Vec3 dir = body.Rotation * originalBoneDerivedRotation * new Vec3(size, 0, 0);
            Ray ray = new Ray(pos, dir);
            RayCastResult res = PhysicsWorld.Instance.RayCast(ray, (int)ContactGroup.CastOnlyContact);

            if (res.Distance != 0)
            {
                // Stiffness
                float forceStiffness = 0, forceDamping = 0;
                forceStiffness = (size - res.Distance) * stiffness;

                // Damping
                if (lastPos != -1.0f)
                {
                    float speed = res.Distance - lastPos;
                    forceDamping = -speed * damping;
                }
                lastPos = res.Distance;

                //EngineConsole.Instance.Print("force(" + bone.Name + ")=" + forceStiffness.ToString() + ", " + forceDamping.ToString());
                body.AddForce(ForceType.LocalAtLocalPos, TickDelta, new Vec3(0, 0, forceStiffness + forceDamping), originalBoneDerivedPosition);

                // Lateral Friction
                Vec3 speedAtWheel = body.LinearVelocity + Vec3.Cross(body.AngularVelocity, body.Rotation * bone.GetDerivedPosition());
                float lateralForce = -Vec3.Dot(speedAtWheel, body.Rotation * Vec3.XAxis) * 0.3f;
                body.AddForce(ForceType.LocalAtLocalPos, TickDelta, new Vec3(lateralForce, 0, 0), bone.GetDerivedPosition());

                // Longitudinal Friction
                float longitudinalForce = -Vec3.Dot(speedAtWheel, body.Rotation * Vec3.YAxis) * 0.001f;
                body.AddForce(ForceType.LocalAtLocalPos, TickDelta, new Vec3(0, longitudinalForce, 0), bone.GetDerivedPosition());

                bone.Position = originalBonePosition - new Vec3(0, 0, res.Distance);
                float wheelRadius = 0.0439f;
                mesh.PositionOffset = originalBoneDerivedPosition - new Vec3(0, 0, res.Distance - wheelRadius);
            }
        }

        public void ForceCallback(Body body, float timestep, int threadindex)
        {
            var data = body.UserData as PhysicsControlData;
            if (data != null)
            {
                body.AddForce(data.Force * body.Mass);
                data.Force = Vector3.ZERO;
                body.AddTorque(data.Torque * body.Mass);
                data.Torque = Vector3.ZERO;
            }

            if (body.Position.y < -10) body.AddBouyancyForce(1030, 0.0020F, 0.0020F, Vector3.NEGATIVE_UNIT_Y * 9.8f, Plane );
        }

        /// <summary>
        /// This will whack the body by the explosion.
        /// NOTE:  Only call from within the Body.ApplyForceAndTorque callback
        /// </summary>
        public void ApplyForceToBody(Body body)
        {
            //TODO:  This needs to add some rotation.  Otherwise it just looks odd (everything is too even)

            Vector3D explosiveForce = GetForceAtPoint(body.Position);
            if (explosiveForce.X != 0d || explosiveForce.Y != 0d || explosiveForce.Z != 0d)
            {
                body.AddForce(explosiveForce);
            }
        }

        private void FixPositionsAndVelocities_ORIG(Body body)
        {
            const double RETURNVELOCITY = 0d;
            double ZACCEL = 10;

            // Get the center of mass in world coords
            Point3D position = body.Position;

            if (_boundryMin != null)        // if min is non null, _boundryMax is also non null.  I don't want to waste the processor checking that each frame
            {
                #region Stay inside bounding box

                // Set the velocity going away to zero, apply a force
                //NOTE:  Position is the center of mass, so if the position is past the boundry, that means the body was travelling too fast for newton to bounce
                //it back (there is a wall at the boundry position).  So this logic is an extra helper

                Vector3D velocity = body.Velocity;    // already in world coords
                bool modifiedVelocity = false;

                #region X

                if (position.X < _boundryMin.Value.X)
                {
                    if (velocity.X < 0)
                    {
                        velocity.X = RETURNVELOCITY;
                        modifiedVelocity = true;
                    }

                    body.AddForce(new Vector3D(body.Mass * ZACCEL, 0, 0));       // Apply a constant acceleration until it hits zero
                }
                else if (position.X > _boundryMax.Value.X)
                {
                    if (velocity.X > 0)
                    {
                        velocity.X = -RETURNVELOCITY;
                        modifiedVelocity = true;
                    }

                    body.AddForce(new Vector3D(body.Mass * ZACCEL * -1, 0, 0));       // Apply a constant acceleration until it hits zero
                }

                #endregion
                #region Y

                if (position.Y < _boundryMin.Value.Y)
                {
                    if (velocity.Y < 0)
                    {
                        velocity.Y = RETURNVELOCITY;
                        modifiedVelocity = true;
                    }

                    body.AddForce(new Vector3D(0, body.Mass * ZACCEL, 0));       // Apply a constant acceleration until it hits zero
                }
                else if (position.Y > _boundryMax.Value.Y)
                {
                    if (velocity.Y > 0)
                    {
                        velocity.Y = -RETURNVELOCITY;
                        modifiedVelocity = true;
                    }

                    body.AddForce(new Vector3D(0, body.Mass * ZACCEL * -1, 0));       // Apply a constant acceleration until it hits zero
                }

                #endregion
                #region Z

                if (position.Z < _boundryMin.Value.Z)
                {
                    if (velocity.Z < 0)
                    {
                        velocity.Z = RETURNVELOCITY;
                        modifiedVelocity = true;
                    }

                    body.AddForce(new Vector3D(0, 0, body.Mass * ZACCEL));       // Apply a constant acceleration until it hits zero
                }
                else if (position.Z > _boundryMax.Value.Z)
                {
                    if (velocity.Z > 0)
                    {
                        velocity.Z = -RETURNVELOCITY;
                        modifiedVelocity = true;
                    }

                    body.AddForce(new Vector3D(0, 0, body.Mass * ZACCEL * -1));       // Apply a constant acceleration until it hits zero
                }

                #endregion

                if (modifiedVelocity)
                {
                    body.Velocity = velocity;        // already in world coords
                }

                #endregion
            }

//.........这里部分代码省略.........

        private void DoForce(Body otherbody, Body thisbody)
        {
            float velocity = 0;
            //if(MaxVelocity <= Velocity)

            //if(MaxVelocity <= Velocity) //)this.GroundRelativeVelocity.Length())
            //{
            velocity = this.GroundRelativeVelocity.Length() + 1000f; //(speedpersecpersec)
            //}
            //else
            //{
            //    if (velocity >= MaxVelocity)
            //        velocity = MaxVelocity;
            //    else if (Velocity < 1)
            //    {
            //        velocity = 0f;
            //    }

            //}

            Vec3 vector = otherbody.Position - thisbody.Position;
            //vector.Z += 3f;
            vector.Normalize();
            otherbody.AddForce(ForceType.GlobalAtLocalPos, TickDelta, vector * (velocity * 2), otherbody.Position);
            //thisbody.AddForce(ForceType.GlobalAtGlobalPos, TickDelta, -vector * velocity, thisbody.Position);
        }

        protected override void OnTick()
        {
            base.OnTick();

            if (firstWay == true)
            {
                ActivateWayMovement();
            }

            UpdateGeneralTask();
            CalculateThings();

            chassisBody = PhysicsModel.GetBody("main");
            if (chassisBody == null)
            {
                Log.Error("Emrah Helli: \"main\" chassisBody dose not exists.");
                return;
            }

            float diff = Position.Z - flyHeight;
            float force = -diff - chassisBody.LinearVelocity.Z;
            MathFunctions.Clamp(ref force, -10, 10);

            chassisBody.AddForce(ForceType.GlobalAtLocalPos, TickDelta,
                new Vec3(0, 0, force * 3) * chassisBody.Mass, new Vec3(0, 0, 1));

            chassisBody.AngularDamping = 1;

            this.flyHeight = TaskPosition.Z;

            float ZA = ZADiffAngle * 4;

            if (ZA < 20 && ZA > -20)
            {
                chassisBody.AngularVelocity = new Vec3
                    (chassisBody.AngularVelocity.X, chassisBody.AngularVelocity.Y, ZA);
            }
            else if (ZA > 20)
            {
                chassisBody.AngularVelocity = new Vec3
                    (chassisBody.AngularVelocity.X, chassisBody.AngularVelocity.Y, -2);
            }
            else if (ZA < -20)
            {
                chassisBody.AngularVelocity = new Vec3
                    (chassisBody.AngularVelocity.X, chassisBody.AngularVelocity.Y, 2);
            }

            chassisBody.AddForce(ForceType.LocalAtLocalPos, TickDelta, new Vec3(Velocity * chassisBody.Mass, 0, 0), new Vec3(-1, 0, 0));
            chassisBody.LinearDamping = 1;
            //check outside Map position
            Bounds checkBounds = Map.Instance.InitialCollisionBounds;
            checkBounds.Expand(new Vec3(300, 300, 10000));
            if (!checkBounds.IsContainsPoint(Position))
                SetDeleted();
        }

        public void TickAndApplyForces(Body body, float TickDelta)
        {
            //mainBody.AddForce(ForceType.LocalAtLocalPos, TickDelta, new Vec3(0, 0, intellect.controlThrust.Value), new Vec3(0, 0, 0));

            //PhysicsWorld.Instance.CreateFixedJoint(body,)

            /*body.LinearVelocity = new Vec3(0, 10, -4);
            body.AngularVelocity = Vec3.Zero;
            body.Rotation = Quat.Identity;*/

            Vec3 speed = body.LinearVelocity;
            Vec3 omega = body.AngularVelocity;

            // Apply Thrust
            //EngineConsole.Instance.Print("speed = " + speed.ToString());
            EngineConsole.Instance.Print("thrustControl = " + awesomeAircraft.controlThrust.Value.ToString());
            float airspeed_scale = 1.0f - speed.Length() / handling.speedMax;
            float thrustPower = awesomeAircraft.controlThrust.Value * handling.accelMax * airspeed_scale;
            body.AddForce(ForceType.LocalAtLocalPos, TickDelta, thrustPower * Vec3.YAxis, new Vec3(0, 5, 0));

            if (Utils.LogOn)
                totalTime += 0.02f;
            //Utils.Write(totalTime.ToString() + "," + thrustPower.ToString() + ",,");
            //Utils.Write(Utils.VectToString(body.Position-Utils.LogPosInitial) + ",," + body.Rotation.ToString() + ",,");
            //Utils.Write(Utils.VectToString(speed) + ",," + Utils.VectToString(omega) + ",,");

            int i = 0;
            foreach (Aerofoil aerofoil in aerofoils)
            {
                Vec3 speedAtAerofoil = speed + Vec3.Cross(omega, body.Rotation * aerofoil.position);

                float density = 5;
                Vec3 liftL, dragL, forceappL, pitch_forceL, pitch_forceappL;
                Mat3 M3Inv = body.Rotation.ToMat3();
                M3Inv.Inverse();
                aerofoil.get_lift_and_drag(
                    this,
                    -M3Inv * speedAtAerofoil,
                    out liftL, out dragL, out forceappL, out pitch_forceL, out pitch_forceappL,
                    density,
                    i,
                    awesomeAircraft.axisAileron.Value,
                    awesomeAircraft.axisElevator.Value,
                    awesomeAircraft.axisRudder.Value
                );
                float seuil = 100;

                if (liftL.Length() > param.CapForce) liftL *= param.CapForce / liftL.Length();
                if (dragL.Length() > param.CapForce) dragL *= param.CapForce / dragL.Length();
                if (pitch_forceL.Length() > param.CapForce) pitch_forceL *= param.CapForce / pitch_forceL.Length();

                body.AddForce(ForceType.LocalAtLocalPos, TickDelta, liftL, forceappL);
                body.AddForce(ForceType.LocalAtLocalPos, TickDelta, dragL, forceappL);
                body.AddForce(ForceType.LocalAtLocalPos, TickDelta, pitch_forceL, pitch_forceappL);

                /*                Utils.Write(
                                    Utils.VectToString(forceappL) + ",," +
                                    Utils.VectToString(liftL) + ",," +
                                    Utils.VectToString(dragL) + ",," +
                                    Utils.VectToString(pitch_forceappL) + ",," +
                                    Utils.VectToString(pitch_forceL) + ",,"
                                );*/
                Utils.Write(liftL.Length().ToString() + ',' + dragL.Length().ToString() + ',' + pitch_forceL.Length().ToString() + ",,");

                i++;
            }

            Utils.WriteLine("");
        }