private TrafficLight trafficLightRef = null; // if there is a traffic light, stock its reference to check its color
public void UpdateWait()
{
switch (waitType)
{
case WaitType.Crosswalk:
UpdateWaitingCars();
// if this is a simple cross-walk, the walker crosses it when all the cars that were waiting at its arrival are gone
if (carsWaiting.Count == 0)
{
StartGoto();
}
break;
case WaitType.TrafficLight:
// else, simply wait for the traffic light to turn green
if (trafficLightRef.GetColor() == TrafficLight.Color.Green)
{
StartGoto();
}
break;
default:
StartGoto();
break;
}
}
private void OnTriggerStay(Collider other)
{
if (other.name == "Check2") // means the walker arrived at a traffic light
{
trafficLightRef = other.GetComponentInParent <TrafficLight>();
if (trafficLightRef)
{
if (trafficLightRef.GetColor() == TrafficLight.Color.Red || trafficLightRef.GetColor() == TrafficLight.Color.Orange)
{
if (HasToCross(trafficLightRef.transform.parent)) // if the light is not green, the walker has to stop
{
StartWait();
waitType = WaitType.TrafficLight;
ChooseWaitPos();
}
}
}
}
}
void Update()
{
lifeTimer += Time.deltaTime;
RaycastHit hit;
// the traffic lights work with triggers, so we need to ignore them to be sure the car is sensed even if it is inside one
if (Physics.Raycast(transform.position, transform.forward, out hit, maxDetectionDistance, int.MaxValue, QueryTriggerInteraction.Ignore))
{
// we only detect cars for now, we could also detect walkers
// this part should also be improved using a collider to detect everything that is around the car and not only straight ahead
// we could also implement a prediction algorithm to prevent collisions with cars coming from the sides
if (hit.transform.gameObject.GetComponent <Car>())
{
carAhead = hit.transform.gameObject; // check if there is a car not far ahead
}
}
if (!destinationValid) // if this bool is set to true, it means the destination has not been set
{ // so we don't do anything (the destination should be correct for the next frame)
return;
}
if (destinationChanged)
{
agent.SetDestination(destination);
destinationChanged = false;
} // when the destination changes, we let a frame to update all intern path-finding values, just in case
else if (agent.remainingDistance < agent.stoppingDistance && lifeTimer > 0.1f) // lifeTimer is used to avoid cars being destroyed on their first frame
{
// once the car has reached its destination
if (spawn)
{
// call the spawner's remove function that takes care of everything
spawn.RemoveCar(gameObject);
}
else
{
// if the spanwer isn't referenced, simply destroy it (which shouldn't happen, but I'd rather have this security)
Destroy(gameObject);
}
}
else // this part is the main behaviour, where we manage speed
{
if (walkersWaiting.Count != 0) // this list is only updated when the car is waiting at a traffic light
{ // so if the count is != from 0, this means there are walkers crossing the road or willing to
// therefore we stop the car
currentSpeed -= acceleration * Time.deltaTime * stopMultiplier;
if (currentSpeed < 0f)
{
currentSpeed = 0f;
}
}
else if (trafficLight != null) // if there is nobody waiting to cross the road, we look at the traffic light
{ // it doesn't count the walkers who arrived after the car, it's a "first arrived -> first gone"
if (trafficLight.GetColor() == TrafficLight.Color.Green)
{
trafficLight = null; // if it is green, the car passes and has no longer need of looking at this traffic light
}
else if (trafficLight.GetColor() == TrafficLight.Color.Red)
{
// if it is red, we stop the car
currentSpeed -= acceleration * Time.deltaTime * stopMultiplier;
if (currentSpeed < 0f)
{
currentSpeed = 0f;
}
}
// if it is orange, we keep the previous behaviour
// if it turns to red before the car has passed, it will stop
// when the car passes the cross-walk, it will stop looking at the traffic light (this is coded in the OnTriggerExit at the end of this script)
}
else if (carAhead != null) // if there is a car ahead, we regulate the speed according to the distance
{
if (Vector3.Distance(transform.position, carAhead.transform.position) < agent.radius * 2.5f) // if it is too close, we break instantly
{ // we know all cars have the same radius here, else we would have to add both agents' radius, here we can simply double it
// we also add an arbitrary .5 to let a little space between the cars
currentSpeed = 0f; // this is an emergency case, normally the car reduces its speed slowly and stops before to come this close (at least if the stopMultiplier is high enough)
}
else if (Vector3.Distance(transform.position, carAhead.transform.position) < stopStartDistance)
{
// if the car is within the specified range, gently stop the car
currentSpeed -= acceleration * Time.deltaTime * stopMultiplier;
if (currentSpeed < 0f)
{
currentSpeed = 0f;
}
}
else // if the car is too far away, apply normal behaviour
{ // which is to accelerate until max speed
currentSpeed += acceleration * Time.deltaTime;
if (currentSpeed > maxSpeed)
{
currentSpeed = maxSpeed;
}
}
}
else // if the car is not at a traffic light and there is no car ahead, simply accelerate until full speed
{
currentSpeed += acceleration * Time.deltaTime;
if (currentSpeed > maxSpeed)
{
currentSpeed = maxSpeed;
}
}
// apply speed to the NavMeshAgent
transform.forward = (destination - transform.position).normalized;
agent.velocity = transform.forward * currentSpeed;
}
// no matter the behaviour
// check the reference walkers list and the current walkers list to know if a walker is gone
// if a walker is gone, remove it so that the car will be able to move when there is none left
if (refWalkersWaiting != null)
{
if (refWalkersWaiting.Count < refCount)
{
bool present = false;
do
{
foreach (GameObject go in walkersWaiting)
{
present = false;
foreach (GameObject refGO in refWalkersWaiting)
{
if (refGO == go)
{
present = true;
break;
}
}
if (!present)
{
walkersWaiting.Remove(go);
break;
}
}
} while (!present && walkersWaiting.Count > 0);
}
refCount = refWalkersWaiting.Count;
}
}