using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Car {
private Route route;
public Road road;
public float roadPositon = 0f, speed = 0f, brakingAcceleration, acceleration, airResistance, t;
private int roadIndex = 0;
private GameObject gameObject;
public Config config;
public Vector3 position, direction;
public bool isAlive = true;
private CarData carData;
private float brakingTime, brakingDistance;
public Car(Route route, Transform parent, Config config) {
this.route = route;
this.config = config;
road = route.roads[0];
foreach (Road currentRoad in route.roads) {
currentRoad.carsOnRoute.Add(this);
}
gameObject = new GameObject();
FlatCircleRenderer renderer = new FlatCircleRenderer(0.8f, 0.2f, 32, 0.01f);
MeshRenderer meshRenderer = gameObject.AddComponent<MeshRenderer>();
meshRenderer.material = config.carAccelerationMaterial;
meshRenderer.receiveShadows = false;
gameObject.AddComponent<MeshFilter>().mesh = renderer.mesh;
gameObject.transform.parent = parent;
GameObject carMesh = new GameObject();
carMesh.AddComponent<MeshRenderer>().material = config.carMaterial;
carMesh.AddComponent<MeshFilter>().mesh = config.carMesh;
carMesh.transform.parent = gameObject.transform;
carData = gameObject.AddComponent<CarData>();
carData.car = this;
position = road.path.getPosition(0f);
carData.Update();
brakingAcceleration = 0.2f * -Physics.gravity.y;
acceleration = config.carTorque / (config.carWheelRadius * config.carMass);
airResistance = config.carAirResistanceModifier * config.carFrontalArea * config.airDensity * 0.5f;
updateBrakingParameters();
}
private void updateBrakingParameters() {
float B = - airResistance;
float A = - 0.02f * (-Physics.gravity.y) - 0.2f * (-Physics.gravity.y);
float sqrtAB = Mathf.Sqrt(A * B);
float sqrtAbyB = Mathf.Sqrt(A / B);
float offset = Mathf.Atan(1f / sqrtAbyB * speed);
brakingTime = offset;
brakingDistance = ((float)(Mathf.Log((float)System.Math.Cosh(sqrtAB * brakingTime - offset)) - Mathf.Log((float)System.Math.Cosh(offset)))) / B;
}
private void incrementRoad() {
road.carsOnRoute.Remove(this);
roadPositon -= road.path.length;
roadIndex++;
if (roadIndex == route.roads.Count) {
GameObject.Destroy(gameObject);
road.carsOnRoute.Remove(this);
isAlive = false;
return;
}
road = route.roads[roadIndex];
}
private float getMaxSpeed(Road road, float distance) {
return Mathf.Sqrt((float)(-Mathf.Abs(road.path.getRadius(road.path.getT(distance))) /
0.2 * Physics.gravity.y));
}
private bool needsBraking(float totalDistance, float maxSpeed) {
if (totalDistance < 0) {
return true;
}
float B = - airResistance;
float A = - 0.02f * (-Physics.gravity.y) - 0.2f * (-Physics.gravity.y);
float sqrtAB = Mathf.Sqrt(A * B);
float sqrtAbyB = Mathf.Sqrt(A / B);
float offset = Mathf.Atan(1f / sqrtAbyB * speed);
float time = - (offset + Mathf.Atan(1f / sqrtAbyB * maxSpeed)) / sqrtAB;
float distance = (-Mathf.Log(Mathf.Cos(sqrtAB * time - offset)) + Mathf.Log(Mathf.Cos(offset))) / B;
return totalDistance <= distance;
}
private bool needsBrakingForCar(Car car) {
Road conflict = car.road;
float otherDistance = conflict.path.length - car.roadPositon;
for (int i = car.roadIndex; !this.route.roads.Contains(conflict) && i < car.route.roads.Count;) {
i++;
conflict = car.route.roads[i];
otherDistance += conflict.path.length;
}
otherDistance -= conflict.path.length;
float thisDistance = - this.roadPositon;
for (int i = this.roadIndex ; i < this.route.roads.Count && this.route.roads[i] != conflict; i++) {
thisDistance += this.route.roads[i].path.length;
}
float time = Mathf.Max(0.5f, thisDistance / speed);
float otherTraveledDistance = car.speed * time;
float currentCarDistance = thisDistance - otherDistance;
float projectedDistance = otherTraveledDistance - otherDistance;
if (currentCarDistance < 0 || currentCarDistance > car.brakingDistance + 3f) {
return false;
}
if (currentCarDistance > 0 && currentCarDistance < 3) {
Debug.DrawLine(position + 1.5f * Vector3.up, car.position + 2 * Vector3.up, Color.blue, 0f, false);
return true;
}
if (projectedDistance > 0 && projectedDistance < 4) {
Debug.DrawLine(position + 1.5f * Vector3.up, car.position + 2 * Vector3.up, Color.yellow, 0f, false);
return true;
}
if (needsBraking(Mathf.Min(projectedDistance, currentCarDistance) - 3f, car.speed)) {
Debug.DrawLine(position + 1.5f * Vector3.up, car.position + 2 * Vector3.up, Color.red, 0f, false);
return true;
}
return false;
}
private bool isBraking() {
float stoppingDistance = Mathf.Min(brakingDistance, 1f);
Road currentRoad = road;
float currentRoadPosition = roadPositon;
int currentRoadIndex = roadIndex;
int steps = 30;
for (int i = 1; i <= steps; i++) {
currentRoadPosition += stoppingDistance / steps;
float totalDistance = stoppingDistance / steps * i;
while (currentRoadPosition >= currentRoad.path.length) {
currentRoadIndex++;
if (currentRoadIndex == route.roads.Count) {
goto end;
}
currentRoadPosition -= currentRoad.path.length;
currentRoad = route.roads[currentRoadIndex];
}
if (needsBraking(totalDistance, getMaxSpeed(currentRoad, currentRoadPosition))) {
// avoid escaping in corners
return true;
}
}
end:
List<Car> carsToCheck = new List<Car>();
for (int i = this.roadIndex; i < this.route.roads.Count; i++) {
foreach (Car car in this.route.roads[i].carsOnRoute) {
if (!carsToCheck.Contains(car)) {
carsToCheck.Add(car);
}
}
}
foreach (Car car in carsToCheck) {
if (car != this && needsBrakingForCar(car)) {
return true;
}
}
return false;
}
private static float atanh(float x) {
return 0.5f * (Mathf.Log(1 + x) - Mathf.Log(1 - x));
}
private void applyAcceleration(float A, float B, float deltaT) {
if (A * B > 0) {
// currently braking probably
if (speed == 0) {
return;
}
float sqrtAB = Mathf.Sqrt(A * B);
float sqrtAbyB = Mathf.Sqrt(A / B);
float offset = Mathf.Atan(1f / sqrtAbyB * speed);
speed = - sqrtAbyB * Mathf.Tan(sqrtAB * deltaT - offset);
roadPositon += (-Mathf.Log(Mathf.Cos(sqrtAB * deltaT - offset)) + Mathf.Log(Mathf.Cos(offset))) / B;
} else {
float sqrtAB = Mathf.Sqrt(-A * B);
float sqrtAbyB = Mathf.Sqrt(-A / B);
float offset = atanh(1.0f / sqrtAbyB * speed);
speed = sqrtAbyB * (float) System.Math.Tanh(sqrtAB * deltaT + offset);
roadPositon += ((float)(Mathf.Log((float)System.Math.Cosh(sqrtAB * deltaT - offset)) - Mathf.Log((float)System.Math.Cosh(offset)))) / B;
}
}
public void step(float deltaTime) {
airResistance = config.carAirResistanceModifier * config.carFrontalArea * config.airDensity * 0.5f;
updateBrakingParameters();
float B = - airResistance;
float A = - 0.02f * (-Physics.gravity.y);
if (isBraking()) {
gameObject.GetComponent<MeshRenderer>().material = config.carBrakingMaterial;
A -= 0.2f * (-Physics.gravity.y);
} else {
gameObject.GetComponent<MeshRenderer>().material = config.carAccelerationMaterial;
if (speed > 0) {
A += Mathf.Min(config.power / speed, 10);
} else {
A += 10f;
}
}
applyAcceleration(A, B, deltaTime);
speed = Mathf.Max(0, speed);
while (roadPositon > road.path.length) {
incrementRoad();
}
t = road.path.getT(roadPositon);
position = road.path.getPosition(t);
direction = road.path.getDirection(t);
direction.Normalize();
}
}
