update

Assets/frictions/default.tire

@@ -1,5 +1,18 @@
 {
-  "Pacejka": {},
+  "Pacejka": {
+    "Lateral": {
+      "B": 12,
+      "C": 1.3,
+      "D": 1.8,
+      "E": -1.8
+    },
+    "Longitudinal": {
+      "B": 10.86,
+      "C": 2.15,
+      "D": 2,
+      "E": 0.992
+    }
+  },
   "RollResistanceLin": 0.001,
   "RollResistanceQuad": 1E-06,
   "__references": [],

Code/Base/Powertrain/PowerWheel.cs

@@ -7,7 +7,11 @@ public class PowerWheel : PowertrainComponent
 {
 	[Property] public VeloXWheel Wheel { get; set; }
 
-	public override float QueryInertia() => Wheel.Inertia;
+	public override float QueryInertia()
+	{
+		float dtScale = Math.Clamp( Time.Delta, 0.01f, 0.05f ) / 0.005f;
+		return Wheel.BaseInertia * dtScale;
+	}
 
 	public override float QueryAngularVelocity( float angularVelocity )
 	{
@@ -19,7 +23,8 @@ public class PowerWheel : PowertrainComponent
 		Wheel.AutoPhysics = false;
 		Wheel.Torque = torque;
 		Wheel.Brake = Vehicle.Brake;
-
+		Inertia = Wheel.BaseInertia + inertia;
+		Wheel.Inertia = inertia;
 		Wheel.DoPhysics( Vehicle );
 
 		angularVelocity = Wheel.AngularVelocity;

Code/Base/VeloXBase.Phys.cs

@@ -1,4 +1,7 @@
-namespace VeloX;
+using Sandbox;
+using System;
+
+namespace VeloX;
 
 public abstract partial class VeloXBase
 {
@@ -19,6 +22,20 @@ public abstract partial class VeloXBase
 			foreach ( var v in Wheels )
 				if ( v.AutoPhysics ) v.DoPhysics( this );
 
+		var totalSpeed = TotalSpeed + Math.Abs( Body.AngularVelocity.z );
+
+		var factor = 1 - Math.Clamp( totalSpeed / 30, 0, 1 );
+
+		if ( factor > 0.1f )
+		{
+			var vel = Body.Velocity;
+
+			var rt = WorldRotation.Right;
+
+			var force = rt.Dot( vel ) / Time.Delta * mass * factor * rt;
+			Body.ApplyForce( -force );
+		}
+
 		Body.ApplyTorque( angForce );
 	}
 }

Code/Base/VeloXBase.cs

@@ -15,7 +15,7 @@ public abstract partial class VeloXBase : Component
 	[Property, Group( "Components" )] public Rigidbody Body { get; protected set; }
 	[Property, Group( "Components" )] public Collider Collider { get; protected set; }
 
-	[Sync] public Angles SteerAngle { get; set; }
+	[Sync( SyncFlags.Interpolate )] public Angles SteerAngle { get; set; }
 
 	public Vector3 LocalVelocity;
 	public float ForwardSpeed;

Code/Base/Wheel/Pacejka.cs

@@ -1,347 +1,43 @@
 using Sandbox;
 using Sandbox.Services;
 using System;
+using System.Threading;
 
 namespace VeloX;
 public class Pacejka
 {
-	public struct LateralForce()
+	public class PacejkaPreset
 	{
-		[Description( "Shape factor" )]
-		[Range( 1, 3 )] public float a0 = 1.4f;        // 0
+		[KeyProperty] public float B { get; set; } = 10.86f;
+		[KeyProperty] public float C { get; set; } = 2.15f;
+		[KeyProperty] public float D { get; set; } = 0.933f;
+		[KeyProperty] public float E { get; set; } = 0.992f;
 
-		[Description( "Load infl on lat friction coeff (*1000) (1/kN)" )]
-		[Range( -100, 100 )] public float a1 = -0f;    // 1
+		public float Evaluate( float slip ) => D * MathF.Sin( C * MathF.Atan( B * slip - E * (B * slip - MathF.Atan( B * slip )) ) );
 
-		[Description( "Lateral friction coefficient at load = 0 (*1000)" )]
-		[Range( 1, 2500 )] public float a2 = 1688f;    // 2
-
-		[Description( "Maximum stiffness (N/deg)" )]
-		[Range( 1, 5000 )] public float a3 = 2400f;    // 3
-
-		[Description( "Load at maximum stiffness (kN)" )]
-		[Range( -100, 100 )] public float a4 = 6.026f; // 4
-
-		[Description( "Camber infiuence on stiffness (%/deg/100)" )]
-		[Range( -10, 10 )] public float a5 = 0f;       // 5
-
-		[Description( "Curvature change with load" )]
-		[Range( -10, 10 )] public float a6 = -0.359f;  // 6
-
-		[Description( "Curvature at load = 0" )]
-		[Range( -10, 10 )] public float a7 = 1.0f;     // 7
-
-		[Description( "Horizontal shift because of camber (deg/deg)" )]
-		[Range( -10, 10 )] public float a8 = 0f;       // 8
-
-		[Description( "Load influence on horizontal shift (deg/kN)" )]
-		[Range( -10, 10 )] public float a9 = -0.00611f;// 9
-
-		[Description( "Horizontal shift at load = 0 (deg)" )]
-		[Range( -10, 10 )] public float a10 = -0.0322f;// 10
-
-		[Description( "Camber influence on vertical shift (N/deg/kN)" )]
-		[Range( -10, 100 )] public float a111 = 0f;    // 11
-
-		[Description( "Camber influence on vertical shift (N/deg/kN**2" )]
-		[Range( -10, 10 )] public float a112 = 0f;     // 12
-
-		[Description( "Load influence on vertical shift (N/kN)" )]
-		[Range( -100, 100 )] public float a12 = 0f;    // 13
-
-		[Description( "Vertical shift at load = 0 (N)" )]
-		[Range( -10, 10 )] public float a13 = 0f;      // 14
-	}
-
-	public struct LongitudinalForce()
+		public float GetPeakSlip()
 		{
-		[Description( "Shape factor" )]
-		[Range( 1, 3 )] public float b0 = 1.65f;       // 0 
+			float peakSlip = -1;
+			float yMax = 0;
 
-		[Description( "Load infl on long friction coeff (*1000) (1/kN)" )]
-		[Range( -300, 300 )] public float b1 = 0f;     // 1 
-
-		[Description( "Longitudinal friction coefficient at load = 0 (*1000)" )]
-		[Range( -10, 10 )] public float b2 = 1690f;    // 2 
-
-		[Description( "Curvature factor of stiffness (N/%/kN**2)" )]
-		[Range( -100, 100 )] public float b3 = 0f;     // 3 
-
-		[Description( "Change of stiffness with load at load = 0 (N/%/kN)" )]
-		[Range( -1000, 1000 )] public float b4 = 229f; // 4 
-
-		[Description( "Change of progressivity of stiffness/load (1/kN)" )]
-		[Range( -10, 10 )] public float b5 = 0f;       // 5 
-
-		[Description( "Curvature change with load" )]
-		[Range( -10, 10 )] public float b6 = 0f;       // 6 
-
-		[Description( "Curvature change with load" )]
-		[Range( -10, 10 )] public float b7 = 0f;       // 7 
-
-		[Description( "Curvature at load = 0" )]
-		[Range( -10, 10 )] public float b8 = -10f;     // 7 
-
-		[Description( "Load influence on horizontal shift (%/kN)" )]
-		[Range( -10, 10 )] public float b9 = 0f;       // 9 
-
-		[Description( "Horizontal shift at load = 0 (%)" )]
-		[Range( -10, 10 )] public float b10 = 0f;      // 10 
-
-		[Description( "Load influence on vertical shift (N/kN)" )]
-		[Range( -10, 10 )] public float b11 = 0f;      // 10 
-
-		[Description( "Vertical shift at load = 0 (N)" )]
-		[Range( -10, 10 )] public float b12 = 0f;      // 10 
-	}
-
-
-	public struct AligningMoment()
+			for ( float i = 0; i < 1f; i += 0.01f )
 			{
-		[Description( "Shape factor" )]
-		[Range( 1, 7 )] public float c0 = 2.0f;        // 0
-
-		[Description( "Load influence of peak value (Nm/kN**2)" )]
-		[Range( -10, 10 )] public float c1 = -3.8f;    // 1
-
-		[Description( "Load influence of peak value (Nm/kN)" )]
-		[Range( -10, 10 )] public float c2 = -3.14f;   // 2
-
-		[Description( "Curvature factor of stiffness (Nm/deg/kN**2" )]
-		[Range( -10, 10 )] public float c3 = -1.16f;   // 3
-
-		[Description( "Change of stiffness with load at load = 0 (Nm/deg/kN)" )]
-		[Range( -100, 100 )] public float c4 = -7.2f;  // 4
-
-		[Description( "Change of progressivity of stiffness/load (1/kN)" )]
-		[Range( -10, 10 )] public float c5 = 0.0f;     // 5
-
-		[Description( "Camber influence on stiffness (%/deg/100)" )]
-		[Range( -10, 10 )] public float c6 = 0.0f;     // 6
-
-		[Description( "Curvature change with load" )]
-		[Range( -10, 10 )] public float c7 = 0.044f;   // 7
-
-		[Description( "Curvature change with load" )]
-		[Range( -10, 10 )] public float c8 = -0.58f;   // 8
-
-		[Description( "Curvature at load = 0" )]
-		[Range( -10, 10 )] public float c9 = 0.18f;    // 9
-
-		[Description( "Camber influence of stiffness" )]
-		[Range( -10, 10 )] public float c10 = 0.0f;    // 10
-
-		[Description( "Camber influence on horizontal shift (deg/deg)" )]
-		[Range( -10, 10 )] public float c11 = 0.0f;    // 11
-
-		[Description( "Load influence on horizontal shift (deg/kN)" )]
-		[Range( -10, 10 )] public float c12 = 0.0f;    // 12
-
-		[Description( "Horizontal shift at load = 0 (deg)" )]
-		[Range( -10, 10 )] public float c13 = 0.0f;    // 13
-
-		[Description( "Camber influence on vertical shift (Nm/deg/kN**2" )]
-		[Range( -10, 10 )] public float c14 = 0.14f;   // 14
-
-		[Description( "Camber influence on vertical shift (Nm/deg/kN)" )]
-		[Range( -10, 10 )] public float c15 = -1.029f; // 15
-
-		[Description( "Load influence on vertical shift (Nm/kN)" )]
-		[Range( -10, 10 )] public float c16 = 0.0f;    // 16
-
-		[Description( "Vertical shift at load = 0 (Nm)" )]
-		[Range( -10, 10 )] public float c17 = 0.0f;    // 17
-	}
-	public struct CombiningForce
-	{
-		public float gy1 = 1;     // 0
-		public float gy2 = 1;    // 1
-		public float gx1 = 1;   // 2
-		public float gx2 = 1f;   // 3
-
-		public CombiningForce()
+				float y = Evaluate( i );
+				if ( y > yMax )
 				{
+					yMax = y;
+					peakSlip = i;
 				}
 			}
 
-
-	public LateralForce Lateral = new();
-	public LongitudinalForce Longitudinal = new();
-	public AligningMoment Aligning = new();
-	public CombiningForce Combining = new();
-
-
-
-	/// pacejka magic formula for longitudinal force
-	public float PacejkaFx( float sigma, float Fz, float friction_coeff )
-	{
-		var b = Longitudinal;
-
-		// shape factor
-		float C = b.b0;
-
-		// peak factor
-		float D = (b.b1 * Fz + b.b2) * Fz;
-
-		// stiffness at sigma = 0
-		float BCD = (b.b3 * Fz + b.b4) * Fz * MathF.Exp( -b.b5 * Fz );
-
-		// stiffness factor
-		float B = BCD / (C * D);
-
-		// curvature factor
-		float E = (b.b6 * Fz + b.b7) * Fz + b.b8;
-
-		// horizontal shift
-		float Sh = b.b9 * Fz + b.b10;
-
-		// composite
-		float S = 100 * sigma + Sh;
-
-		// longitudinal force
-		float BS = B * S;
-		float Fx = D * Sin3Pi2( C * MathF.Atan( BS - E * (BS - MathF.Atan( BS )) ) );
-
-		// scale by surface friction
-		Fx *= friction_coeff;
-
-		return Fx;
+			return peakSlip;
 		}
 
-	/// pacejka magic formula for lateral force
-	public float PacejkaFy( float alpha, float Fz, float gamma, float friction_coeff, out float camber_alpha )
-	{
-		var a = Lateral;
-
-		// shape factor
-		float C = a.a0;
-
-		// peak factor
-		float D = (a.a1 * Fz + a.a2) * Fz;
-
-		// stiffness at alpha = 0
-		float BCD = a.a3 * Sin2Atan( Fz, a.a4 ) * (1 - a.a5 * MathF.Abs( gamma ));
-
-		// stiffness factor
-		float B = BCD / (C * D);
-
-		// curvature factor
-		float E = a.a6 * Fz + a.a7;
-
-		// horizontal shift
-		float Sh = a.a8 * gamma + a.a9 * Fz + a.a10;
-
-		// vertical shift
-		float Sv = ((a.a111 * Fz + a.a112) * gamma + a.a12) * Fz + a.a13;
-
-		// composite slip angle
-		float S = alpha + Sh;
-
-		// lateral force
-		float BS = B * S;
-		float Fy = D * Sin3Pi2( C * MathF.Atan( BS - E * (BS - MathF.Atan( BS )) ) ) + Sv;
-
-		// scale by surface friction
-		Fy *= friction_coeff;
-		camber_alpha = Sh + Sv / BCD * friction_coeff;
-
-		return Fy;
 	}
 
-	/// pacejka magic formula for aligning torque
-	public float PacejkaMz( float alpha, float Fz, float gamma, float friction_coeff )
-	{
-		var c = Aligning;
+	public PacejkaPreset Lateral { get; set; } = new();
+	public PacejkaPreset Longitudinal { get; set; } = new();
 
-		// shape factor
-		float C = c.c0;
-
-		// peak factor
-		float D = (c.c1 * Fz + c.c2) * Fz;
-
-		// stiffness at alpha = 0
-		float BCD = (c.c3 * Fz + c.c4) * Fz * (1 - c.c6 * MathF.Abs( gamma )) * MathF.Exp( -c.c5 * Fz );
-
-		// stiffness factor
-		float B = BCD / (C * D);
-
-		// curvature factor
-		float E = (c.c7 * Fz * Fz + c.c8 * Fz + c.c9) * (1 - c.c10 * MathF.Abs( gamma ));
-
-		// horizontal shift
-		float Sh = c.c11 * gamma + c.c12 * Fz + c.c13;
-
-		// composite slip angle
-		float S = alpha + Sh;
-
-		// vertical shift
-		float Sv = (c.c14 * Fz * Fz + c.c15 * Fz) * gamma + c.c16 * Fz + c.c17;
-
-		// self-aligning torque
-		float BS = B * S;
-		float Mz = D * Sin3Pi2( C * MathF.Atan( BS - E * (BS - MathF.Atan( BS )) ) ) + Sv;
-
-		// scale by surface friction
-		Mz *= friction_coeff;
-
-		return Mz;
-	}
-
-	/// pacejka magic formula for the longitudinal combining factor
-	public float PacejkaGx( float sigma, float alpha )
-	{
-		var p = Combining;
-		float a = p.gx2 * sigma;
-		float b = p.gx1 * alpha;
-		float c = a * a + 1;
-		return MathF.Sqrt( c / (c + b * b) );
-	}
-
-	/// pacejka magic formula for the lateral combining factor
-	public float PacejkaGy( float sigma, float alpha )
-	{
-		var p = Combining;
-		float a = p.gy2 * alpha;
-		float b = p.gy1 * sigma;
-		float c = a * a + 1;
-		return MathF.Sqrt( c / (c + b * b) );
-	}
-
-	public static float SinPi2( float x )
-	{
-		float s = x * x;
-		float p = -1.8447486103462252e-04f;
-		p = 8.3109378830028557e-03f + p * s;
-		p = -1.6665578084732124e-01f + p * s;
-		p = 1.0f + p * s;
-		return p * x;
-	}
-
-	// Вычисление sin(x) для |x| <= 3π/2
-	public static float Sin3Pi2( float x )
-	{
-		// Приведение x к интервалу [-π, π]
-		if ( x < -MathF.PI )
-			x += 2 * MathF.PI;
-		else if ( x > MathF.PI )
-			x -= 2 * MathF.PI;
-
-		// Отражение в интервал [-π/2, π/2] с использованием симметрии
-		if ( x < -MathF.PI / 2 )
-			x = -MathF.PI - x;
-		else if ( x > MathF.PI / 2 )
-			x = MathF.PI - x;
-
-		return SinPi2( x );
-	}
-
-	public static float Sin2Atan( float x )
-	{
-		return 2 * x / (x * x + 1);
-	}
-
-	public static float Sin2Atan( float y, float x )
-	{
-		return 2 * x * y / (x * x + y * y);
-	}
+	public float PacejkaFx( float slip ) => Longitudinal.Evaluate( slip );
+	public float PacejkaFy( float slip ) => Lateral.Evaluate( slip );
 }

Code/Base/Wheel/Suspension/BasicSuspension.cs

@@ -0,0 +1,18 @@
+namespace VeloX;
+
+public class BasicSuspension
+{
+	private readonly Hinge Hinge;
+
+	public BasicSuspension( Vector3 wheel, Vector3 hingeBody, Vector3 hingeWheel )
+	{
+		Vector3 hingePoint = wheel - (hingeWheel - hingeBody);
+		Hinge = new Hinge( hingePoint, hingeWheel - hingeBody );
+	}
+
+	public virtual void GetWheelTransform( float travel, out Rotation rotation, out Vector3 position )
+	{
+		rotation = Rotation.Identity;
+		position = Hinge.Rotate( travel );
+	}
+}

Code/Base/Wheel/Suspension/Hinge.cs

@@ -0,0 +1,26 @@
+using System;
+
+namespace VeloX;
+
+internal readonly struct Hinge( Vector3 hinge_anchor, Vector3 hinge_arm )
+{
+	[Description( "the point that the wheels are rotated around as the suspension compresses" )]
+	public readonly Vector3 Anchor = hinge_anchor;
+
+	[Description( "anchor to wheel vector" )]
+	public readonly Vector3 Arm = hinge_arm;
+
+	[Description( "arm length squared" )]
+	public readonly float LengthSquared = hinge_arm.Dot( hinge_arm );
+
+	[Description( "1 / arm length in hinge axis normal plane" )]
+	public readonly float NormXY = 1 / MathF.Sqrt( hinge_arm.x * hinge_arm.x + hinge_arm.y * hinge_arm.y );
+
+	public readonly Vector3 Rotate( float travel )
+	{
+		float z = Arm.z + travel;
+		float lengthSq = MathF.Max( LengthSquared - z * z, 0.0f );
+		float nxy = NormXY * MathF.Sqrt( lengthSq );
+		return Anchor + new Vector3( Arm.x * nxy, Arm.y * nxy, z );
+	}
+}

Code/Base/Wheel/Suspension/MacPhersonSuspension.cs

@@ -0,0 +1,32 @@
+using Sandbox;
+using System;
+
+namespace VeloX;
+public class MacPhersonSuspension
+{
+	public readonly Vector3 WheelOffset;
+	public readonly Vector3 UprightTop;
+	public readonly Vector3 UprightAxis;
+	private readonly Hinge Hinge;
+
+	public MacPhersonSuspension( Vector3 wheel, Vector3 strutBody, Vector3 strutWheel, Vector3 hingeBody )
+	{
+		WheelOffset = wheel - strutWheel;
+		UprightTop = strutBody;
+		UprightAxis = (strutBody - strutWheel).Normal;
+		Hinge = new( hingeBody, strutWheel - hingeBody );
+	}
+
+	public void GetWheelTransform( float travel, out Rotation rotation, out Vector3 position )
+	{
+		Vector3 hingeEnd = Hinge.Rotate( travel );
+		Vector3 uprightAxisNew = (UprightTop - hingeEnd).Normal;
+
+		rotation = Rotation.FromAxis(
+			Vector3.Cross( UprightAxis, uprightAxisNew ),
+			MathF.Acos( Vector3.Dot( UprightAxis, uprightAxisNew ) ).RadianToDegree()
+		);
+
+		position = hingeEnd + WheelOffset.Transform( rotation );
+	}
+}

Code/Base/Wheel/TirePreset.cs

@@ -24,12 +24,25 @@ public class TirePreset : GameResource
 		return resistance;
 	}
 
-	public void ComputeSlip( float vlon, float vlat, float vrot, out float slip_ratio, out float slip_angle )
+	public static void ComputeSlip( float lon_velocity, float lat_velocity, float rot_velocity, float wheel_radius, out float slip_ratio, out float slip_angle )
 	{
-		float rvlon = 1 / MathF.Max( MathF.Abs( vlon ), 1E-3f );
-		float vslip = vrot - vlon;
-		slip_ratio = vslip * rvlon;
-		slip_angle = -MathF.Atan( vlat * rvlon );
+		var abs_lon = Math.Max( MathF.Abs( lon_velocity ), 1e-3f );
+
+		slip_ratio = lon_velocity - rot_velocity * wheel_radius;
+
+		if ( abs_lon >= 0.005f )
+			slip_ratio /= abs_lon;
+		else
+			slip_ratio *= abs_lon;
+
+		if ( abs_lon >= 0.5f )
+			slip_angle = MathF.Atan2( -lat_velocity, abs_lon ).RadianToDegree() / 50f;
+		else
+			slip_angle = -lat_velocity * (0.01f / Time.Delta);
+
+		slip_ratio = Math.Clamp( slip_ratio, -1, 1 );
+		slip_angle = Math.Clamp( slip_angle, -1, 1 );
+
 	}
 
 	/// approximate asin(x) = x + x^3/6 for +-18 deg range
@@ -39,60 +52,6 @@ public class TirePreset : GameResource
 		return ((1 / 6.0f) * (sc * sc) + 1) * sc;
 	}
 
-	public struct TireState
-	{
-		public float friction = 0;  // surface friction coefficient
-		public float camber = 0;  // tire camber angle relative to track surface
-		public float vcam = 0;  // camber thrust induced lateral slip velocity
-		public float slip = 0;  // ratio of tire contact patch speed to road speed
-		public float slip_angle = 0;  // the angle between the wheel heading and the wheel velocity
-		public float ideal_slip = 0;  // peak force slip ratio
-		public float ideal_slip_angle = 0;  // peak force slip angle
-		public float fx = 0;  // positive during traction
-		public float fy = 0;  // positive in a right turn
-		public float mz = 0;  // positive in a left turn
-
-		public TireState()
-		{
-		}
-	};
-
-	public void ComputeState(
-		float normal_force,
-		float rot_velocity,
-		float lon_velocity,
-		float lat_velocity,
-		float camber_angle,
-		out TireState s
-	)
-	{
-		s = new TireState
-		{
-			camber = camber_angle,
-			friction = 1.0f
-		};
-
-		if ( normal_force * s.friction < 1E-6f )
-		{
-			s.slip = s.slip_angle = 0;
-			s.fx = s.fy = s.mz = 0;
-			return;
-		}
-
-		float Fz = Math.Min( normal_force * 1E-3f, 30f );
-		ComputeSlip( lon_velocity, lat_velocity, rot_velocity, out float slip, out float slip_angle );
-		float sigma = slip;
-		float alpha = slip_angle.RadianToDegree();
-		float gamma = s.camber.RadianToDegree();
-		float Fx = Pacejka.PacejkaFx( sigma, Fz, s.friction );
-		float Fy = Pacejka.PacejkaFy( alpha, Fz, gamma, s.friction, out float camber_alpha );
-		s.vcam = ComputeCamberVelocity( camber_alpha.DegreeToRadian(), lon_velocity );
-		s.slip = slip;
-		s.slip_angle = slip_angle;
-		s.fx = Fx;
-		s.fy = Fy;
-	}
-
 	public static float ComputeCamberVelocity( float sa, float vx )
 	{
 		float tansa = (1 / 3.0f * (sa * sa) + 1) * sa;

Code/Base/Wheel/VeloXWheel.Sound.cs

@@ -0,0 +1,28 @@
+using Sandbox;
+using System;
+
+namespace VeloX;
+
+
+public partial class VeloXWheel : Component
+{
+	private RealTimeUntil expandSoundCD;
+	private RealTimeUntil contractSoundCD;
+	private void DoSuspensionSounds( VeloXBase vehicle, float change )
+	{
+		if ( change > 0.1f && expandSoundCD )
+		{
+			expandSoundCD = 0.3f;
+			var sound = Sound.Play( vehicle.SuspensionUpSound, WorldPosition );
+			sound.Volume = Math.Clamp( Math.Abs( change ) * 5f, 0, 0.5f );
+		}
+
+		if ( change < -0.1f && contractSoundCD )
+		{
+			contractSoundCD = 0.3f;
+			change = MathF.Abs( change );
+			var sound = Sound.Play( change > 0.3f ? vehicle.SuspensionHeavySound : vehicle.SuspensionDownSound, WorldPosition );
+			sound.Volume = Math.Clamp( change * 5f, 0, 1 );
+		}
+	}
+}

Code/Base/Wheel/VeloXWheel.cs

@@ -1,9 +1,16 @@
 using Sandbox;
+using Sandbox.Rendering;
 using Sandbox.Services;
+using Sandbox.UI;
 using System;
 using System.Collections.Specialized;
+using System.Diagnostics.Metrics;
 using System.Numerics;
 using System.Text.RegularExpressions;
+using System.Threading;
+using static Sandbox.CameraComponent;
+using static Sandbox.Package;
+using static Sandbox.SkinnedModelRenderer;
 
 namespace VeloX;
 
@@ -18,8 +25,8 @@ public partial class VeloXWheel : Component
 	[Property] public float SlipCircleShape { get; set; } = 1.05f;
 	[Property] public TirePreset TirePreset { get; set; }
 	[Property] public float Width { get; set; } = 6;
-	public float SideSlip => sideFriction.Slip.MeterToInch();
-	public float ForwardSlip => forwardFriction.Slip.MeterToInch();
+	public float SideSlip { get; private set; }
+	public float ForwardSlip { get; private set; }
 	[Sync] public float Torque { get; set; }
 	[Sync, Range( 0, 1 )] public float Brake { get; set; }
 	[Property] float BrakePowerMax { get; set; } = 3000;
@@ -38,8 +45,8 @@ public partial class VeloXWheel : Component
 
 	public float Spin { get; private set; }
 
-	public float RPM { get => angularVelocity * 60f / MathF.Tau; set => angularVelocity = value / (60 / MathF.Tau); }
-	public float AngularVelocity => angularVelocity;
+	public float RPM { get => angularVelocity * 30f / MathF.PI; set => angularVelocity = value / (30f / MathF.PI); }
+	public float AngularVelocity { get => angularVelocity; set => angularVelocity = value; }
 
 	internal float DistributionFactor { get; set; }
 
@@ -53,21 +60,23 @@ public partial class VeloXWheel : Component
 	private float angularVelocity;
 	private float load;
 	private float lastFraction;
-	private RealTimeUntil expandSoundCD;
-	private RealTimeUntil contractSoundCD;
 
 	private Vector3 contactPos;
 	private Vector3 forward;
 	private Vector3 right;
 	private Vector3 up;
 
-	private Friction forwardFriction;
-	private Friction sideFriction;
+	private float forwardFriction;
+	private float sideFriction;
 	private Vector3 force;
 	public float CounterTorque { get; private set; }
 
-	private float BaseInertia => 0.5f * Mass * MathF.Pow( Radius.InchToMeter(), 2 );
-	public float Inertia => BaseInertia;
+	internal float BaseInertia => 0.5f * Mass * MathF.Pow( Radius.InchToMeter(), 2 );
+	public float Inertia
+	{
+		get => BaseInertia + inertia;
+		set => inertia = value;
+	}
 
 
 	protected override void OnAwake()
@@ -77,24 +86,6 @@ public partial class VeloXWheel : Component
 			StartPos = LocalPosition;
 	}
 
-	private void DoSuspensionSounds( VeloXBase vehicle, float change )
-	{
-		if ( change > 0.1f && expandSoundCD )
-		{
-			expandSoundCD = 0.3f;
-			var sound = Sound.Play( vehicle.SuspensionUpSound, WorldPosition );
-			sound.Volume = Math.Clamp( Math.Abs( change ) * 5f, 0, 0.5f );
-		}
-
-		if ( change < -0.1f && contractSoundCD )
-		{
-			contractSoundCD = 0.3f;
-			change = MathF.Abs( change );
-			var sound = Sound.Play( change > 0.3f ? vehicle.SuspensionHeavySound : vehicle.SuspensionDownSound, WorldPosition );
-			sound.Volume = Math.Clamp( change * 5f, 0, 1 );
-		}
-	}
-
 	internal void Update( VeloXBase vehicle, in float dt )
 	{
 		UpdateVisuals( vehicle, dt );
@@ -102,18 +93,14 @@ public partial class VeloXWheel : Component
 
 	private void UpdateVisuals( VeloXBase vehicle, in float dt )
 	{
-		var entityAngles = vehicle.WorldRotation;
-
-		Spin -= angularVelocity.MeterToInch() * dt;
-
+		Spin -= angularVelocity.RadianToDegree() * dt;
 		WorldRotation = vehicle.WorldTransform.RotationToWorld( GetSteer( vehicle.SteerAngle.yaw ) ) * Rotation.FromAxis( Vector3.Right, Spin );
-
 	}
 
 	private Rotation GetSteer( float steer )
 	{
 
-		float angle = (steer * SteerMultiplier).DegreeToRadian();
+		float angle = (-steer * SteerMultiplier).DegreeToRadian();
 
 		float t = MathF.Tan( (MathF.PI / 2) - angle ) - Ackermann;
 		float steering_angle = MathF.CopySign( float.Pi / 2, t ) - MathF.Atan( t );
@@ -126,6 +113,100 @@ public partial class VeloXWheel : Component
 
 	private static float GetLongitudinalLoadCoefficient( float load ) => 11000 * (1 - MathF.Exp( -0.00014f * load ));
 	private static float GetLateralLoadCoefficient( float load ) => 18000 * (1 - MathF.Exp( -0.0001f * load ));
+	private float inertia;
+
+
+	private (float, float, float, float) StepLongitudinal( float Tm, float Tb, float Vx, float W, float Lc, float R, float I )
+	{
+		float wInit = W;
+		float vxAbs = Math.Abs( Vx );
+		float Sx;
+		if ( Lc < 0.01f )
+		{
+			Sx = 0;
+		}
+		else if ( vxAbs >= 0.01f )
+		{
+			Sx = (W * R - Vx) / vxAbs;
+		}
+		else
+		{
+			Sx = (W * R - Vx) * 0.6f;
+		}
+
+		Sx = Math.Clamp( Sx, -1, 1 );
+
+		W += Tm / I * Time.Delta;
+
+		Tb *= W > 0 ? -1 : 1;
+
+		float tbCap = Math.Abs( W ) * I / Time.Delta;
+		float tbr = Math.Abs( Tb ) - Math.Abs( tbCap );
+		tbr = Math.Max( tbr, 0 );
+
+		Tb = Math.Clamp( Tb, -tbCap, tbCap );
+
+		W += Tb / I * Time.Delta;
+
+		float maxTorque = TirePreset.Pacejka.PacejkaFx( Math.Abs( Sx ) ) * Lc * R;
+
+		float errorTorque = (W - Vx / R) * I / Time.Delta;
+		float surfaceTorque = Math.Clamp( errorTorque, -maxTorque, maxTorque );
+
+		W -= surfaceTorque / I * Time.Delta;
+		float Fx = surfaceTorque / R;
+
+		tbr *= (W > 0 ? -1 : 1);
+		float TbCap2 = Math.Abs( W ) * I / Time.Delta;
+		float Tb2 = Math.Clamp( tbr, -TbCap2, TbCap2 );
+		W += Tb2 / I * Time.Delta;
+
+		float deltaOmegaTorque = (W - wInit) * I / Time.Delta;
+		float Tcnt = -surfaceTorque + Tb + Tb2 - deltaOmegaTorque;
+
+		return (W, Sx, Fx, Tcnt);
+	}
+
+	private void StepLateral( float Vx, float Vy, float Lc, out float Sy, out float Fy )
+	{
+		float VxAbs = Math.Abs( Vx );
+
+		if ( Lc < 0.01f )
+		{
+			Sy = 0;
+		}
+		else if ( VxAbs > 0.1f )
+		{
+
+			Sy = MathX.RadianToDegree( MathF.Atan( Vy / VxAbs ) ) / 50;
+		}
+		else
+		{
+
+			Sy = Vy * (0.003f / Time.Delta);
+		}
+
+		Sy = Math.Clamp( Sy, -1, 1 );
+		float slipSign = Sy < 0 ? -1 : 1;
+		Fy = -slipSign * TirePreset.Pacejka.PacejkaFy( Math.Abs( Sy ) ) * Lc;
+	}
+
+	private void SlipCircle( float Sx, float Sy, float Fx, ref float Fy )
+	{
+		float SxAbs = Math.Abs( Sx );
+		if ( SxAbs > 0.01f )
+		{
+			float SxClamped = Math.Clamp( Sx, -1, 1 );
+			float SyClamped = Math.Clamp( Sy, -1, 1 );
+			Vector2 combinedSlip = new( SxClamped * 1.05f, SyClamped );
+			Vector2 slipDir = combinedSlip.Normal;
+
+			float F = MathF.Sqrt( Fx * Fx + Fy * Fy );
+			float absSlipDirY = Math.Abs( slipDir.y );
+
+			Fy = F * absSlipDirY * (Fy < 0 ? -1 : 1);
+		}
+	}
 
 	public void DoPhysics( VeloXBase vehicle )
 	{
@@ -133,10 +214,6 @@ public partial class VeloXWheel : Component
 
 		var ang = vehicle.WorldTransform.RotationToWorld( GetSteer( vehicle.SteerAngle.yaw ) );
 
-		forward = ang.Forward;
-		right = ang.Right;
-		up = ang.Up;
-
 		var maxLen = SuspensionLength;
 
 		var endPos = pos + ang.Down * maxLen;
@@ -145,123 +222,95 @@ public partial class VeloXWheel : Component
 					.Cylinder( Width, Radius, pos, endPos )
 					.Rotated( vehicle.WorldTransform.Rotation * CylinderOffset )
 					.UseRenderMeshes( false )
-					.UseHitPosition( false )
+					.UseHitPosition( true )
 					.WithoutTags( vehicle.WheelIgnoredTags )
 					.Run();
 
+		forward = Vector3.VectorPlaneProject( ang.Forward, Trace.Normal );
+		right = Vector3.VectorPlaneProject( ang.Right, Trace.Normal );
+
 		var fraction = Trace.Fraction;
 
-		contactPos = pos - maxLen * fraction * up;
+		contactPos = pos - maxLen * fraction * ang.Up;
 
 		LocalPosition = vehicle.WorldTransform.PointToLocal( contactPos );
 
 		DoSuspensionSounds( vehicle, fraction - lastFraction );
 		lastFraction = fraction;
 
-		var normal = Trace.Normal;
-
-		var vel = vehicle.Body.GetVelocityAtPoint( pos );
-
-		vel.x = vel.x.InchToMeter();
-		vel.y = vel.y.InchToMeter();
-		vel.z = vel.z.InchToMeter();
-
 		if ( !IsOnGround )
-		{
-			forwardFriction = new Friction();
-			sideFriction = new Friction();
 			return;
-		}
+
+		var vel = vehicle.Body.GetVelocityAtPoint( contactPos );
 
 		var offset = maxLen - (fraction * maxLen);
-		var springForce = (offset * SpringStrength);
+		var springForce = offset * SpringStrength;
 		var damperForce = (lastSpringOffset - offset) * SpringDamper;
+
 		lastSpringOffset = offset;
-		force = (springForce - damperForce) * MathF.Max( 0, up.Dot( normal ) ) * normal / Time.Delta;
 
-		// Vector3.CalculateVelocityOffset is broken (need fix)
-		//var velU = normal.Dot( vel ).MeterToInch();
-		//if ( velU < 0 && offset + Math.Abs( velU * dt ) > SuspensionLength )
-		//{
-		//	var (linearVel, angularVel) = vehicle.Body.PhysicsBody.CalculateVelocityOffset( (-velU.InchToMeter() / dt) * normal, pos );
-		//	vehicle.Body.Velocity += linearVel;
-		//	vehicle.Body.AngularVelocity += angularVel;
-		//}
 
-		load = Math.Max( force.z.InchToMeter(), 0 );
+		var velU = Trace.Normal.Dot( vel );
 
-		if ( IsOnGround )
+		if ( velU < 0 && offset + Math.Abs( velU * Time.Delta ) > SuspensionLength )
 		{
-			float forwardSpeed = vel.Dot( forward );
-			float sideSpeed = vel.Dot( right );
+			vehicle.Body.CalculateVelocityOffset( -velU / Time.Delta * Trace.Normal, pos, out var linearImp, out var angularImp );
 
-			float camber_rad = CamberAngle.DegreeToRadian();
+			vehicle.Body.Velocity += linearImp;
+			vehicle.Body.AngularVelocity += angularImp;
+			vehicle.Body.CalculateVelocityOffset( Trace.HitPosition - (contactPos + Trace.Normal * velU * Time.Delta), pos, out var lin, out _ );
 
-			TirePreset.ComputeState(
-				load,
-				angularVelocity,
+			vehicle.WorldPosition += lin / Time.Delta;
+			damperForce = 0;
+
+		}
+
+		force = (springForce - damperForce) * Trace.Normal;
+
+		load = Math.Max( springForce - damperForce, 0 );
+		float R = Radius.InchToMeter();
+
+		float forwardSpeed = vel.Dot( forward ).InchToMeter();
+		float sideSpeed = vel.Dot( right ).InchToMeter();
+
+		float longitudinalLoadCoefficient = GetLongitudinalLoadCoefficient( load );
+		float lateralLoadCoefficient = GetLateralLoadCoefficient( load );
+
+		float F_roll = TirePreset.GetRollingResistance( angularVelocity * R, 1.0f ) * 10000;
+	
+		( float W, float Sx, float Fx, float counterTq) = StepLongitudinal(
+			Torque,
+			Brake * BrakePowerMax + F_roll,
 			forwardSpeed,
-				sideSpeed,
-				camber_rad,
-				out var tireState
+			angularVelocity,
+			longitudinalLoadCoefficient,
+			R,
+			Inertia
 		);
 
-			float linearSpeed = angularVelocity * Radius.InchToMeter();
-			float F_roll = TirePreset.GetRollingResistance( linearSpeed, 1.0f );
-			F_roll = -MathF.Sign( forwardSpeed ) * F_roll;
+		StepLateral( forwardSpeed, sideSpeed, lateralLoadCoefficient, out float Sy, out float Fy );
 
-			float Fx_total = tireState.fx + F_roll;
+		SlipCircle( Sx, Sy, Fx, ref Fy );
 
-			float R = Radius.InchToMeter();
-			float I = Inertia;
-			float T_brake = Brake * BrakePowerMax;
+		CounterTorque = counterTq;
+		angularVelocity = W;
 
-			if ( angularVelocity > 0 ) T_brake = -T_brake;
-			else T_brake = angularVelocity < 0 ? T_brake : -MathF.Sign( Torque ) * T_brake;
-
-			float totalTorque = Torque + T_brake - Fx_total * R;
-			angularVelocity += totalTorque / I * Time.Delta;
-
-			forwardFriction = new Friction()
-			{
-				Slip = tireState.slip,
-				Force = Fx_total.MeterToInch(),
-				Speed = forwardSpeed
-			};
-
-			sideFriction = new Friction()
-			{
-				Slip = tireState.slip_angle,
-				Force = tireState.fy.MeterToInch(),
-				Speed = sideSpeed
-			};
-			Vector3 frictionForce = forward * forwardFriction.Force + right * sideFriction.Force;
-			vehicle.Body.ApplyForceAt( contactPos, force + frictionForce );
-
-		}
-		else
-		{
-			// Колесо в воздухе: сбрасываем силы
-			forwardFriction = new Friction();
-			sideFriction = new Friction();
-
-			// Обновление угловой скорости только от мотора/тормозов
-			float T_brake = Brake * BrakePowerMax;
-
-			if ( angularVelocity > 0 ) T_brake = -T_brake;
-			else T_brake = angularVelocity < 0 ? T_brake : -MathF.Sign( Torque ) * T_brake;
-			angularVelocity += (Torque + T_brake) / Inertia * Time.Delta;
-		}
+		force += forward * Fx;
+		force += right * Fy * Math.Clamp( vehicle.TotalSpeed * 0.005f, 0, 1 );
+		ForwardSlip = Sx;
+		SideSlip = Sy * Math.Clamp( vehicle.TotalSpeed * 0.005f, 0, 1 );
 
+		vehicle.Body.ApplyForceAt( pos, force / Time.Delta );
 
 	}
 
-
-	// debug
+#if DEBUG
 	protected override void OnUpdate()
 	{
-		DebugOverlay.Normal( contactPos, forward * forwardFriction.Force / 10000f, Color.Red, overlay: true );
-		DebugOverlay.Normal( contactPos, right * sideFriction.Force / 10000f, Color.Green, overlay: true );
-		DebugOverlay.Normal( contactPos, up * force / 50000f, Color.Blue, overlay: true );
+		DebugOverlay.Normal( contactPos, forward * forwardFriction, Color.Red, overlay: true );
+		DebugOverlay.Normal( contactPos, right * sideFriction, Color.Green, overlay: true );
+		DebugOverlay.Normal( contactPos, up * force / 1000f, Color.Blue, overlay: true );
 	}
+#endif
+
 }

Code/Car/VeloXCar.Steering.cs

@@ -14,33 +14,40 @@ public partial class VeloXCar
 	[Property, Feature( "Steer" )] public float MaxSteerAngle { get; set; } = 35f;
 
 	[Sync] public float Steering { get; private set; }
-	private float jTurnMultiplier;
 
 	private float inputSteer;
+
+	public static float SignedAngle( Vector3 from, Vector3 to, Vector3 axis )
+	{
+		float unsignedAngle = Vector3.GetAngle( from, to );
+
+		float cross_x = from.y * to.z - from.z * to.y;
+		float cross_y = from.z * to.x - from.x * to.z;
+		float cross_z = from.x * to.y - from.y * to.x;
+		float sign = MathF.Sign( axis.x * cross_x + axis.y * cross_y + axis.z * cross_z );
+		return unsignedAngle * sign;
+	}
+	public float VelocityAngle { get; private set; }
+	public int CarDirection { get { return ForwardSpeed.InchToMeter() < 5 ? 0 : (VelocityAngle < 90 && VelocityAngle > -90 ? 1 : -1); } }
 	private void UpdateSteering( float dt )
 	{
 		var inputSteer = Input.AnalogMove.y;
-		var absInputSteer = Math.Abs( inputSteer );
 
-		var sideSlip = Math.Clamp( avgSideSlip, -1, 1 );
 
-		var steerConeFactor = Math.Clamp( TotalSpeed / SteerConeMaxSpeed, 0, 1 );
-		var steerCone = 1 - steerConeFactor * (1 - SteerConeMaxAngle);
+		VelocityAngle = 0;// -SignedAngle( Body.Velocity, WorldRotation.Forward, WorldRotation.Up );
 
-		steerCone = Math.Clamp( steerCone, Math.Abs( sideSlip ), 1 );
+		//var steerConeFactor = Math.Clamp( TotalSpeed / SteerConeMaxSpeed, 0, 1 );
+		//var steerCone = 1 - steerConeFactor * (1 - SteerConeMaxAngle);
 
-		inputSteer = ExpDecay( this.inputSteer, inputSteer * steerCone, SteerConeChangeRate, dt );
+		inputSteer = ExpDecay( this.inputSteer, inputSteer, SteerConeChangeRate, dt );
 		this.inputSteer = inputSteer;
-		var counterSteer = sideSlip * steerConeFactor * (1 - absInputSteer);
-		counterSteer = Math.Clamp( counterSteer, -1, 1 ) * CounterSteer;
 
-		inputSteer = Math.Clamp( inputSteer + counterSteer, -1, 1 );
+		float target = -inputSteer * MaxSteerAngle;
+		if ( CarDirection > 0 )
+			target -= VelocityAngle * CounterSteer;
+
+		inputSteer = Math.Clamp( inputSteer, -1, 1 );
 		Steering = inputSteer;
-		SteerAngle = new( 0, inputSteer * MaxSteerAngle, 0 );
-
-		if ( ForwardSpeed < -100 )
-			jTurnMultiplier = 0.5f;
-		else
-			jTurnMultiplier = ExpDecay( jTurnMultiplier, 1, 2, dt );
+		SteerAngle = new( 0, target, 0 );
 	}
 }

Code/Car/VeloXCar.Wheel.cs

@@ -2,27 +2,9 @@
 
 public partial class VeloXCar
 {
-	private float avgSideSlip;
-	private float avgPoweredRPM;
-	private float avgForwardSlip;
 	private void WheelThink( in float dt )
 	{
-		float avgRPM = 0, totalSideSlip = 0, totalForwardSlip = 0;
-
 		foreach ( var w in Wheels )
-		{
 			w.Update( this, dt );
-
-			totalSideSlip += w.SideSlip;
-			totalForwardSlip += w.ForwardSlip;
-			var rpm = w.RPM;
-
-			avgRPM += rpm * w.DistributionFactor;
-		}
-
-		avgPoweredRPM = avgRPM;
-		avgSideSlip = totalSideSlip / Wheels.Count;
-		avgForwardSlip = totalForwardSlip / Wheels.Count;
-
 	}
 }

Code/Car/VeloXCar.cs

@@ -7,32 +7,6 @@ namespace VeloX;
 [Title( "VeloX - Car" )]
 public partial class VeloXCar : VeloXBase
 {
-	protected override void OnStart()
-	{
-		base.OnStart();
-		//StreamPlayer = new( Stream );
-		//if ( IsDriver )
-		//{
-		//	UpdateGearList();
-		//	UpdatePowerDistribution();
-		//}
-	}
-
-	protected override void OnUpdate()
-	{
-		base.OnUpdate();
-		//if ( StreamPlayer is not null )
-		//{
-
-		//	StreamPlayer.Throttle = Throttle;
-		//	StreamPlayer.RPMPercent = RPMPercent;
-		//	StreamPlayer.EngineState = EngineState;
-		//	StreamPlayer.IsRedlining = IsRedlining;
-
-		//	StreamPlayer.Update( Time.Delta, WorldPosition );
-		//}
-
-	}
 	protected override void OnFixedUpdate()
 	{
 		if ( !IsDriver )

Code/Utils/PhysicsExtensions.cs

@@ -28,44 +28,38 @@ public static class PhysicsExtensions
 			value.x * (xz2 - wy2) + value.y * (yz2 + wx2) + value.z * (1.0f - xx2 - yy2)
 		);
 	}
+
 	/// <summary>
-	/// Calculates the linear and angular velocities on the center of mass for an offset impulse.
+	/// Calculates the linear and angular velocities on the object's center of mass for an offset impulse.
 	/// </summary>
 	/// <param name="physObj">The physics object</param>
 	/// <param name="impulse">The impulse acting on the object in kg*units/s (World frame)</param>
 	/// <param name="position">The location of the impulse in world coordinates</param>
-	/// <returns>
-	/// Vector1: Linear velocity from the impulse (World frame)
-	/// Vector2: Angular velocity from the impulse (Local frame)
-	/// </returns>
-	public static (Vector3 LinearVelocity, Vector3 AngularVelocity) CalculateVelocityOffset( this PhysicsBody physObj, Vector3 impulse, Vector3 position )
+	/// <param name="LinearVelocity">Linear velocity on center of mass (World frame)</param>
+	/// <param name="AngularVelocity">Angular velocity on center of mass (World frame)</param>
+	public static void CalculateVelocityOffset(
+		this Rigidbody physObj,
+		Vector3 impulse,
+		Vector3 position,
+		out Vector3 LinearVelocity,
+		out Vector3 AngularVelocity )
 	{
 		if ( !physObj.IsValid() || !physObj.MotionEnabled )
-			return (Vector3.Zero, Vector3.Zero);
+		{
+			LinearVelocity = 0;
+			AngularVelocity = 0;
+			return;
+		}
 
+		Vector3 com = physObj.WorldTransform.PointToWorld( physObj.MassCenter );
+		Rotation bodyRot = physObj.PhysicsBody.Rotation;
 
-		Vector3 linearVelocity = impulse / physObj.Mass;
-
-		Vector3 r = position - physObj.MassCenter;
-
-
-		// Calculate torque impulse in world frame: τ = r × impulse
-		Vector3 torqueImpulseWorld = r.Cross( impulse );
-		Rotation worldToLocal = physObj.Rotation.Inverse;
-		Vector3 torqueImpulseLocal = torqueImpulseWorld.Transform( worldToLocal );
-
-		var InverseInertiaDiagLocal = physObj.Inertia.Inverse;
-
-		// Compute angular velocity change in rad/s (local frame)
-		Vector3 angularVelocityRadLocal = new(
-			InverseInertiaDiagLocal.x * torqueImpulseLocal.x,
-			InverseInertiaDiagLocal.y * torqueImpulseLocal.y,
-			InverseInertiaDiagLocal.z * torqueImpulseLocal.z
-		);
-		const float radToDeg = 180f / MathF.PI;
-		Vector3 angularVelocityDegLocal = angularVelocityRadLocal * radToDeg;
-
-		return (linearVelocity, angularVelocityDegLocal);
+		Vector3 r = position - com;
+		Vector3 torque = Vector3.Cross( r, impulse );
+		Vector3 torqueLocal = bodyRot.Inverse * torque;
+		Vector3 angularVelocityLocal = torqueLocal * physObj.PhysicsBody.Inertia.Inverse;
+		AngularVelocity = bodyRot * angularVelocityLocal;
+		LinearVelocity = impulse * (1 / physObj.Mass);
 	}
 
 	/// <summary>
@@ -74,34 +68,31 @@ public static class PhysicsExtensions
 	/// <param name="physObj">The physics object</param>
 	/// <param name="impulse">The impulse acting on the object in kg*units/s (World frame)</param>
 	/// <param name="position">The location of the impulse in world coordinates</param>
-	/// <returns>
-	/// Vector1: Linear impulse on center of mass (World frame)
-	/// Vector2: Angular impulse on center of mass (Local frame)
-	/// </returns>
-	public static (Vector3 LinearImpulse, Vector3 AngularImpulse) CalculateForceOffset(
-		this PhysicsBody physObj,
+	/// <param name="LinearImpulse">Linear impulse on center of mass (World frame)</param>
+	/// <param name="AngularImpulse">Angular impulse on center of mass (World frame)</param>
+	public static void CalculateForceOffset(
+		this Rigidbody physObj,
 		Vector3 impulse,
-		Vector3 position )
+		Vector3 position,
+		out Vector3 LinearImpulse,
+		out Vector3 AngularImpulse )
 	{
 		if ( !physObj.IsValid() || !physObj.MotionEnabled )
 		{
-			return (Vector3.Zero, Vector3.Zero);
+			LinearImpulse = 0;
+			AngularImpulse = 0;
+			return;
 		}
 
-		// 1. Linear impulse is the same as the input impulse (conservation of momentum)
-		Vector3 linearImpulse = impulse;
+		Vector3 com = physObj.WorldTransform.PointToWorld( physObj.MassCenter );
+		Rotation bodyRot = physObj.PhysicsBody.Rotation;
 
-		// 2. Calculate angular impulse (torque) from the offset force
-		// τ = r * F (cross product of position relative to COM and force)
-		Vector3 centerOfMass = physObj.MassCenter;
-		Vector3 relativePosition = position - centerOfMass;
-		Vector3 worldAngularImpulse = relativePosition.Cross( impulse );
-
-		// Convert angular impulse to local space (since we'll use it with LocalInertia)
-		Rotation bodyRotation = physObj.Transform.Rotation;
-		Vector3 localAngularImpulse = bodyRotation.Inverse * worldAngularImpulse;
-
-		return (linearImpulse, localAngularImpulse);
+		Vector3 r = position - com;
+		Vector3 torque = Vector3.Cross( r, impulse );
+		Vector3 torqueLocal = bodyRot.Inverse * torque;
+		Vector3 angularImpulseLocal = torqueLocal * physObj.PhysicsBody.Inertia.Inverse;
+		AngularImpulse = bodyRot * angularImpulseLocal;
+		LinearImpulse = impulse;
 	}
 
 }

Editor/Wheel/PacejkaWidget.cs

@@ -9,7 +9,7 @@ public class PacejkaWidget : ControlObjectWidget
 	public override bool SupportsMultiEdit => false;
 	public override bool IncludeLabel => false;
 
-	[CustomEditor( typeof( Pacejka.LateralForce ) )]
+	[CustomEditor( typeof( Pacejka.PacejkaPreset ) )]
 	private class LateralForceWidget : ControlObjectWidget
 	{
 		public LateralForceWidget( SerializedProperty property ) : base( property, true )
@@ -17,7 +17,7 @@ public class PacejkaWidget : ControlObjectWidget
 			Layout = Layout.Column();
 			Layout.Margin = 8f;
 			Layout.Spacing = 8;
-			foreach ( var item in TypeLibrary.GetType<Pacejka.LateralForce>().Fields )
+			foreach ( var item in TypeLibrary.GetType<Pacejka.PacejkaPreset>().Properties )
 			{
 				var row = Layout.AddRow();
 				row.Spacing = 8;
@@ -27,45 +27,6 @@ public class PacejkaWidget : ControlObjectWidget
 			}
 		}
 	}
-
-	[CustomEditor( typeof( Pacejka.LongitudinalForce ) )]
-	private class LongitudinalForceWidget : ControlObjectWidget
-	{
-		public LongitudinalForceWidget( SerializedProperty property ) : base( property, true )
-		{
-			Layout = Layout.Column();
-			Layout.Margin = 8f;
-			Layout.Spacing = 8;
-			foreach ( var item in TypeLibrary.GetType<Pacejka.LongitudinalForce>().Fields )
-			{
-				var row = Layout.AddRow();
-				row.Spacing = 8;
-				var propetry = SerializedObject.GetProperty( item.Name );
-				row.Add( new Label( propetry.Name ) );
-				row.Add( Create( propetry ) );
-			}
-		}
-	}
-
-	[CustomEditor( typeof( Pacejka.AligningMoment ) )]
-	private class AligningMomentWidget : ControlObjectWidget
-	{
-		public AligningMomentWidget( SerializedProperty property ) : base( property, true )
-		{
-			Layout = Layout.Column();
-			Layout.Margin = 8f;
-			Layout.Spacing = 8;
-			foreach ( var item in TypeLibrary.GetType<Pacejka.AligningMoment>().Fields )
-			{
-				var row = Layout.AddRow();
-				row.Spacing = 8;
-				var propetry = SerializedObject.GetProperty( item.Name );
-				row.Add( new Label( propetry.Name ) );
-				row.Add( Create( propetry ) );
-			}
-		}
-	}
-
 	private Pacejka Pacejka;
 	public PacejkaWidget( SerializedProperty property ) : base( property, true )
 	{
@@ -83,8 +44,5 @@ public class PacejkaWidget : ControlObjectWidget
 		tabs.AddPage( nameof( Pacejka.Longitudinal ), null,
 			Layout.Add( Create( obj.GetProperty( nameof( Pacejka.Longitudinal ) ) ) )
 		);
-		tabs.AddPage( nameof( Pacejka.Aligning ), null,
-			Layout.Add( Create( obj.GetProperty( nameof( Pacejka.Aligning ) ) ) )
-		);
 	}
 }

Editor/Wheel/TirePresetEditor.cs

@@ -1,70 +0,0 @@
-using Editor;
-using Editor.Assets;
-using Editor.Inspectors;
-using Sandbox;
-using static Editor.Inspectors.AssetInspector;
-
-namespace VeloX;
-
-[CanEdit( "asset:tire" )]
-public class TirePresetEditor : Widget, IAssetInspector
-{
-	TirePreset Tire;
-	ControlSheet MainSheet;
-	TirePresetPreview TirePreview;
-	public TirePresetEditor( Widget parent ) : base( parent )
-	{
-		Layout = Layout.Column();
-		Layout.Margin = 4;
-		Layout.Spacing = 4;
-
-		// Create a ontrolSheet that will display all our Properties
-		MainSheet = new ControlSheet();
-		Layout.Add( MainSheet );
-
-		//// Add a randomize button below the ControlSheet
-		//var button = Layout.Add( new Button( "Randomize", "casino", this ) );
-		//button.Clicked += () =>
-		//{
-		//	foreach ( var prop in Test.GetSerialized() )
-		//	{
-		//		// Randomize all the float values from 0-100
-		//		if ( prop.PropertyType != typeof( float ) ) continue;
-		//		prop.SetValue( Random.Shared.Float( 0, 100 ) );
-		//	}
-		//};
-
-		Layout.AddStretchCell();
-
-		RebuildSheet();
-		Focus();
-
-	}
-
-	[EditorEvent.Hotload]
-	void RebuildSheet()
-	{
-		if ( Tire is null ) return;
-		if ( MainSheet is null ) return;
-		MainSheet.Clear( true );
-
-		var so = Tire.GetSerialized();
-		so.OnPropertyChanged += x =>
-		{
-			Tire.StateHasChanged();
-			TirePreview.Widget.UpdatePixmap();
-		};
-		MainSheet.AddObject( so );
-	}
-
-	void IAssetInspector.SetAssetPreview( AssetPreview preview )
-	{
-		TirePreview = preview as TirePresetPreview;
-	}
-
-	public void SetAsset( Asset asset )
-	{
-		Tire = asset.LoadResource<TirePreset>();
-		RebuildSheet();
-	}
-}

Editor/Wheel/TirePresetPreview.cs

@@ -1,7 +1,6 @@
 using Editor;
 using Editor.Assets;
 using Editor.Inspectors;
-using Editor.ShaderGraph.Nodes;
 using Sandbox;
 using System;
 using System.Collections.Generic;
@@ -10,29 +9,17 @@ using System.Threading.Tasks;
 namespace VeloX;
 
 [AssetPreview( "tire" )]
-class TirePresetPreview( Asset asset ) : PixmapAssetPreview( asset )
+class TirePresetPreview : AssetPreview
 {
-
-	private TirePreset Tire = asset.LoadResource<TirePreset>();
+	private Texture texture;
+	public override bool IsAnimatedPreview => false;
+	[Range( 0.01f, 1 )] private float Zoom { get; set; } = 1;
+	private TirePreset Tire;
 	public AssetPreviewWidget Widget { get; private set; }
-	[Range( 100, 10000 )] private float Load { get; set; } = 2500f;
-	[Range( 0, 1 )] private float Zoom { get; set; } = 0;
-	[Range( -10, 10 )] private float Camber { get; set; } = 0;
-
 	public override Widget CreateWidget( Widget parent )
 	{
 		Widget = parent as AssetPreviewWidget;
 
-		Task.Run( async () =>
-		{
-			while ( Widget != null )
-			{
-				await MainThread.Wait();
-				await Widget.UpdatePixmap();
-				await Task.Delay( 100 );
-			}
-		} );
-
 		return null;
 	}
 	public override Widget CreateToolbar()
@@ -43,125 +30,6 @@ class TirePresetPreview( Asset asset ) : PixmapAssetPreview( asset )
 		info.MouseLeftPress = () => OpenSettings( info );
 		return info;
 	}
-	static List<Vector2> pointCache = [];
-	private void DrawPacejka()
-	{
-
-		float load = Load * 0.001f;
-		float zoom = (1.0f - Zoom) * 4.0f + 0.1f;
-		var tire = Tire.Pacejka;
-		var width = Paint.LocalRect.Width;
-		var height = Paint.LocalRect.Height;
-
-
-		{ // draw lateral line
-			pointCache.Clear();
-
-			Paint.SetPen( Color.Red, 1 );
-			float x0 = -zoom * 0.5f * 20.0f;
-			float xn = zoom * 0.5f * 20.0f;
-			float ymin = -1000.0f;
-			float ymax = 1000.0f;
-			int points = 500;
-
-
-			for ( float x = x0; x <= xn; x += (xn - x0) / points )
-			{
-
-				float yval = tire.PacejkaFy( x, load, Camber, 1.0f, out float maxforce ) / load;
-				float xval = width * (x - x0) / (xn - x0);
-				yval /= ymax - ymin;
-				yval = (yval + 1.0f) * 0.5f;
-				yval = 1.0f - yval;
-				yval *= height;
-				if ( x == x0 )
-					pointCache.Add( new( xval, yval ) );
-				else
-					pointCache.Add( new( xval, yval ) );
-			}
-
-			Paint.DrawLine( pointCache );
-		}
-
-		{ // draw longitudinal line
-			pointCache.Clear();
-
-			Paint.SetPen( Color.Blue, 1 );
-			float x0 = -zoom * 0.5f * 10.0f;
-			float xn = zoom * 0.5f * 10.0f;
-			float ymin = -60.0f;
-			float ymax = 60.0f;
-			int points = 500;
-
-			for ( float x = x0; x <= xn; x += (xn - x0) / points )
-			{
-				float yval = tire.PacejkaMz( x, load, Camber * (180.0f / MathF.PI), 1.0f ) / load;
-				float xval = width * (x - x0) / (xn - x0);
-				yval /= ymax - ymin;
-				yval = (yval + 1.0f) * 0.5f;
-				yval = 1.0f - yval;
-				yval *= height;
-				if ( x == x0 )
-					pointCache.Add( new( xval, yval ) );
-				else
-					pointCache.Add( new( xval, yval ) );
-			}
-			Paint.DrawLine( pointCache );
-		}
-
-		{ // draw aligning line
-			pointCache.Clear();
-
-			Paint.SetPen( Color.Green, 1 );
-			float x0 = -zoom * 0.5f;
-			float xn = zoom * 0.5f;
-			float ymin = -1000.0f;
-			float ymax = 1000.0f;
-			int points = 500;
-
-			for ( float x = x0; x <= xn; x += (xn - x0) / points )
-			{
-				float yval = tire.PacejkaFx( x, load, 1.0f ) / load;
-				float xval = width * (x - x0) / (xn - x0);
-				yval /= ymax - ymin;
-				yval = (yval + 1.0f) * 0.5f;
-				yval = 1.0f - yval;
-				yval *= height;
-				if ( x == x0 )
-					pointCache.Add( new( xval, yval ) );
-				else
-					pointCache.Add( new( xval, yval ) );
-			}
-			Paint.DrawLine( pointCache );
-		}
-
-		pointCache.Clear();
-	}
-
-	public override Task RenderToPixmap( Pixmap pixmap )
-	{
-		Paint.ToPixmap( pixmap );
-		Paint.Antialiasing = true;
-
-		Paint.SetBrush( Color.Gray );
-		Paint.DrawRect( Paint.LocalRect );
-		Paint.ClearBrush();
-
-		Paint.SetPen( Color.Black, 1 );
-
-		var width = Paint.LocalRect.Width;
-		var height = Paint.LocalRect.Height;
-		float xc = width / 2;
-		float yc = height / 2;
-
-		Paint.DrawLine( new( xc, 0 ), new( xc, yc * 2 ) );
-		Paint.DrawLine( new( 0, yc ), new( xc * 2, yc ) );
-
-		DrawPacejka();
-
-		return Task.CompletedTask;
-	}
-
 	public void OpenSettings( Widget parent )
 	{
 		var popup = new PopupWidget( parent )
@@ -174,9 +42,7 @@ class TirePresetPreview( Asset asset ) : PixmapAssetPreview( asset )
 
 		var ps = new ControlSheet();
 
-		ps.AddProperty( this, x => x.Load );
 		ps.AddProperty( this, x => x.Zoom );
-		ps.AddProperty( this, x => x.Camber );
 
 		popup.Layout.Add( ps );
 		popup.MaximumWidth = 300;
@@ -185,4 +51,99 @@ class TirePresetPreview( Asset asset ) : PixmapAssetPreview( asset )
 		popup.ConstrainToScreen();
 
 	}
+
+	public override async Task InitializeAsset()
+	{
+		await Task.Yield();
+
+		using ( Scene.Push() )
+		{
+			PrimaryObject = new()
+			{
+				WorldTransform = Transform.Zero
+			};
+
+			var plane = PrimaryObject.AddComponent<ModelRenderer>();
+			plane.Model = Model.Plane;
+			plane.LocalScale = new Vector3( 1, 1, 1 );
+			plane.MaterialOverride = Material.Load( "materials/dev/reflectivity_30.vmat" );
+			plane.Tint = new Color( 0.02f, 0.04f, 0.03f );
+
+			var bounds = PrimaryObject.GetBounds();
+			SceneCenter = bounds.Center;
+			SceneSize = bounds.Size;
+		}
+
+		return;
+	}
+	public override void UpdateScene( float cycle, float timeStep )
+	{
+		if ( !Widget.IsValid() )
+			return;
+
+		Camera.WorldPosition = Vector3.Up * 300;
+		Camera.Orthographic = true;
+		Camera.WorldRotation = new Angles( 90, 0, 0 );
+
+		var bitmap = new Bitmap( 512, 512 );
+
+		Draw( bitmap );
+
+		texture.Clear( Color.Black );
+		//texture.Update( bitmap );
+		DebugOverlaySystem.Current.Texture( texture, new Rect( 0, Widget.Size ) );
+
+		FrameScene();
+	}
+
+	private readonly List<Vector2> pointCache = [];
+
+	public TirePresetPreview( Asset asset ) : base( asset )
+	{
+		texture = Texture.CreateRenderTarget().WithDynamicUsage().WithScreenFormat().WithSize( 512, 512 ).Create();
+		Tire = Asset.LoadResource<TirePreset>();
+	}
+
+	private void DrawPacejka( Bitmap bitmap )
+	{
+		var tire = Tire.Pacejka;
+		var width = bitmap.Width;
+		var height = bitmap.Height;
+
+
+		{ // draw lateral line
+			pointCache.Clear();
+
+			bitmap.SetPen( Color.Red, 1 );
+
+			for ( float x = 0; x <= 1; x += 0.01f )
+			{
+				float val = tire.PacejkaFy( x ) * Zoom;
+				pointCache.Add( new( width * x, height - height * val ) );
+			}
+
+			bitmap.DrawLines( pointCache.ToArray() );
+		}
+
+		{ // draw longitudinal line
+			pointCache.Clear();
+
+			bitmap.SetPen( Color.Green, 1 );
+
+			for ( float x = 0; x <= 1; x += 0.01f )
+			{
+				float val = tire.PacejkaFx( x ) * Zoom;
+				pointCache.Add( new( width * x, height - height * val ) );
+			}
+			bitmap.DrawLines( pointCache.ToArray() );
+		}
+
+		pointCache.Clear();
+	}
+	private void Draw( Bitmap bitmap )
+	{
+		bitmap.Clear( Color.Black );
+		bitmap.SetAntialias( true );
+		DrawPacejka( bitmap );
+	}
 }