Car-Simulation/Car simulation/Car.cs

using static SFML.Window.Mouse;

namespace Car_simulation
{
    public class Car
    {
        public Vector2 Position = new Vector2(0, 0);
        public Vector2 Velocity = new Vector2(0, 0);
        public float Speed => Velocity.Length;

        public float Mass = 1500f; // kg
        public int WheelCount = 4;
        public int DrivenWheels = 2;

        public float ThrottleInput = 0f;
        public float BrakeInput = 0f;
        public float ClutchInput = 1f; // 0 = engaged, 1 = disengaged
        public bool ForceClutch = false;
        public float SteeringInput = 0f;

        // Aerodynamics
        private const float AirDensity = 1.225f;
        public float DragCoefficient = 0.1f;
        public float FrontalArea = 2.2f; // m²
        public float RollingResistanceCoefficient = 0.015f;

        // Components
        public Engine Engine;
        public Drivetrain Drivetrain;
        public WheelSystem WheelSystem;

        private EngineSound _engineSound;
        private bool _audioEnabled = true;

        public Car()
        {
            Engine = new Engine();
            WheelSystem = new WheelSystem();
            Drivetrain = new Drivetrain(Engine, WheelSystem);

            // Initial setup
            WheelSystem.WheelCount = WheelCount;
            WheelSystem.DrivenWheels = DrivenWheels;

            InitializeAudio();
        }

        private void InitializeAudio()
        {
            try
            {
                _engineSound = new EngineSound();
                _engineSound.SetEngineState(Engine.IdleRPM, 0f);
                _engineSound.StartSound();

            }
            catch (Exception ex)
            {
                Console.WriteLine($"Audio initialization failed: {ex.Message}");
                _audioEnabled = false;
            }
        }

        public void Update(float deltaTime)
        {
            Engine.Throttle = ThrottleInput;
            Drivetrain.ClutchEngagement = 1f - ClutchInput; // Convert: 0 input = 1 engagement

            if (ForceClutch)
                Drivetrain.ClutchEngagement = 0f;

            float resistanceTorque = CalculateResistanceTorque();
            WheelSystem.ResistanceTorque = resistanceTorque;

            Drivetrain.Update(deltaTime);
            WheelSystem.ApplyResistance(deltaTime);

            float engineLoad = Drivetrain.CalculateEngineLoad(deltaTime);
            Engine.Update(deltaTime, engineLoad);

            UpdateVehicleMotion(deltaTime);
            ApplyBraking(deltaTime);

            if (_audioEnabled)
            {
                UpdateAudio();
            }
        }

        private void UpdateAudio()
        {
            try
            {
                float throttle = Engine.GetActualThrottle();
                _engineSound.SetEngineState(Engine.RPM, throttle);
            }
            catch (Exception ex)
            {
                Console.WriteLine($"Audio update error: {ex.Message}");
            }
        }

        private void UpdateVehicleMotion(float deltaTime)
        {
            // Calculate net force
            float tractiveForce = CalculateTractiveForce();
            float resistanceForce = CalculateTotalResistanceForce();
            float netForce = tractiveForce - resistanceForce;

            // Calculate acceleration: a = F / m
            float acceleration = netForce / Mass;

            // Update velocity: v = v₀ + a·Δt
            if (Velocity.Length > 0)
            {
                Vector2 direction = Velocity.Normalized();
                float newSpeed = Velocity.Length + acceleration * deltaTime;
                newSpeed = Math.Max(newSpeed, 0); // Don't go backwards without reverse gear
                Velocity = direction * newSpeed;
            }
            else
            {
                // Starting from standstill
                Velocity = new Vector2(acceleration * deltaTime, 0);
            }

            Position += Velocity * deltaTime;

            // Sync wheel speed with actual vehicle speed (with slip allowance)
            float currentWheelSpeed = Velocity.Length;
            WheelSystem.SetSpeed(currentWheelSpeed);
        }

        private float CalculateTractiveForce()
        {
            // 1. Get the torque available at the wheels
            float wheelTorque = Drivetrain.ClutchTorque * Drivetrain.Efficiency;

            // 2. Convert torque to theoretical force: F = τ / r
            float theoreticalForce = wheelTorque / WheelSystem.Radius;

            // 3. Account for weight distribution and driven wheels
            // Normal load on driven wheels = (DrivenWheels / WheelCount) * Weight
            float drivenWheelNormalLoad = (DrivenWheels / (float)WheelCount) * Mass * 9.81f;

            // 4. Calculate maximum tractive force based on friction (tire grip)
            float frictionCoefficient = 1.2f; // Typical tire on dry asphalt
            float maxTractiveForce = drivenWheelNormalLoad * frictionCoefficient;

            // 5. Limit the force by what the tires can actually grip
            // Also handle direction (forward/reverse)
            if (theoreticalForce > 0)
            {
                return Math.Min(theoreticalForce, maxTractiveForce);
            }
            else
            {
                // For reverse or engine braking
                return Math.Max(theoreticalForce, -maxTractiveForce);
            }
        }

        private void ApplyBraking(float deltaTime)
        {
            if (BrakeInput <= 0) return;

            float brakeTorque = BrakeInput * 500f; // 500 Nm max brake torque

            WheelSystem.ApplyTorque(-brakeTorque, deltaTime);
        }

        public float CalculateTotalResistanceForce()
        {
            float dragForce = CalculateDragForce();
            float rollingForce = CalculateRollingResistanceForce();
            return dragForce + rollingForce;
        }

        private float CalculateDragForce()
        {
            // F_drag = 0.5 * ρ * Cd * A * v²
            float speed = Speed;
            return 0.5f * AirDensity * DragCoefficient * FrontalArea * speed * speed;
        }

        private float CalculateRollingResistanceForce()
        {
            // F_rolling = C_r * m * g
            return RollingResistanceCoefficient * Mass * 9.81f;
        }

        // Convert resistance force to wheel torque
        public float CalculateResistanceTorque()
        {
            float totalForce = CalculateTotalResistanceForce();
            return totalForce * WheelSystem.Radius;
        }

        public void DisplayUpdate()
        {
            Console.SetCursorPosition(0, 0);
            Console.WriteLine($"Engine Energy: {Engine.FlywheelEnergy,7:F0} J");
            Console.WriteLine($"Engine Torque: {Engine.GetTorqueOutput(),7:F0} Nm");
            Console.WriteLine($"Engine RPM: {Engine.RPM,7:F0}");
            Console.WriteLine($"Wheel Energy: {WheelSystem.WheelEnergy,7:F0} J");
            Console.WriteLine($"Wheel RPM: {WheelSystem.RPM,7:F0}");
            Console.WriteLine($"Vehicle: {Speed * 3.6f,7:F1} km/h");
            Console.WriteLine($"Throttle: {Engine.GetActualThrottle() * 100,6:F1}%");
            Console.WriteLine($"Power: {Engine.CurrentPower / 1000,6:F1} kW");
            Console.WriteLine($"Transmitted: {Drivetrain.TransmittedPower / 1000,6:F1} kW");
            Console.WriteLine($"Brake: {BrakeInput * 100,6:F1}%");
            Console.WriteLine($"Clutch: {ClutchInput * 100,6:F1}% disengaged");
            Console.WriteLine($"Speed Diff: {Drivetrain.GetSpeedDifferenceRPM(),6:F0} RPM");
            Console.WriteLine($"Clutch T: {Drivetrain.ClutchTorque,6:F0} Nm");
            Console.WriteLine($"Resistance: {CalculateTotalResistanceForce(),6:F1} N");
            Console.WriteLine($"Drag: {CalculateDragForce(),6:F1} N");
            Console.WriteLine($"Rolling: {CalculateRollingResistanceForce(),6:F1} N");
            Console.WriteLine($"Gear: {Drivetrain.GetCurrentGearName(),3} (Ratio: {Drivetrain.GearRatio:F2}:1)");
        }
    }
}