public void ArriveAtPosition()
{
Steerable steerer = new Steerable();
steerer.MaxSpeed = 10;
steerer.Acceleration = 20.02345f;
steerer.Target = Vector2.One * 100;
steerer.Behaviors.Add(new ArriveBehavior());
float[] targetSpeed = new float[] { 2, 4, 6, 8, 10, 10, 10 };
for (int i = 0; i < targetSpeed.Length; ++i)
{
steerer.Update(ElapsedTime);
Assert.AreEqual <int>((int)targetSpeed[i], (int)Math.Round(steerer.Speed));
}
bool hasStopped = false;
bool hasFullyStopped = false;
for (int i = 0; i < 2000; ++i)
{
steerer.Update(ElapsedTime);
if (hasStopped)
{
Assert.IsTrue(steerer.Speed < steerer.MaxSpeed);
if (steerer.Speed <= 0)
{
hasFullyStopped = true;
Assert.IsTrue(Vector2.Distance(Vector2.One * 100, steerer.Position) < 1f);
}
if (hasFullyStopped)
{
Assert.IsTrue(steerer.Speed <= float.Epsilon);
}
}
if ((int)Math.Round(steerer.Speed) != (int)Math.Round(steerer.MaxSpeed))
{
hasStopped = true;
}
}
Assert.IsTrue(hasStopped);
Assert.IsTrue(hasFullyStopped);
}
public void SeekToPositionMaxAcceleration()
{
Steerable steerer = new Steerable();
steerer.MaxSpeed = 10;
steerer.Acceleration = float.MaxValue;
steerer.Target = Vector2.One * 1000;
steerer.Behaviors.Add(new SeekBehavior());
float[] targetSpeed = new float[] { 10, 10, 10 };
for (int i = 0; i < targetSpeed.Length; ++i)
{
steerer.Update(ElapsedTime);
Assert.AreEqual <int>((int)targetSpeed[i], (int)Math.Round(steerer.Speed));
}
}
public void ArriveAtPositionNearby()
{
Steerable steerer = new Steerable();
steerer.MaxSpeed = 10;
steerer.Acceleration = 20.02345f;
steerer.Target = Vector2.One * 5;
steerer.Behaviors.Add(new ArriveBehavior());
bool hasStopped = false;
bool hasFullyStopped = false;
float previousSpeed = float.MinValue;
for (int i = 0; i < 200; ++i)
{
steerer.Update(ElapsedTime);
if (hasStopped)
{
Assert.IsTrue(steerer.Speed < steerer.MaxSpeed);
if (steerer.Speed <= 0)
{
hasFullyStopped = true;
Assert.IsTrue(Vector2.Distance(Vector2.One * 5, steerer.Position) < 0.5f);
}
if (hasFullyStopped)
{
Assert.IsTrue(steerer.Speed <= float.Epsilon);
}
}
if (steerer.Speed < previousSpeed)
{
hasStopped = true;
}
previousSpeed = steerer.Speed;
}
Assert.IsTrue(hasStopped);
Assert.IsTrue(hasFullyStopped);
}
/// <summary>
/// Updates the specified game time.
/// </summary>
public void Update(float elapsedTime)
{
if (elapsedTime <= 0)
{
return;
}
Vector2 currentPosition = steerable.Position;
steerable.Update(elapsedTime);
if (steerable.Speed > 0 && steerable.Force != Vector2.Zero && State == NavigatorState.Stopped)
{
State = NavigatorState.Moving;
OnStarted();
return;
}
if (steerable.Speed <= 0 && steerable.Force == Vector2.Zero)
{
if (State == NavigatorState.Moving)
{
if (waypoints.Count > 0)
{
MoveTo(waypoints.Dequeue());
}
else
{
Stop();
}
}
return;
}
Vector2 nextPosition = steerable.Position;
// Compute the normal of the terrain. We don't want to our entity
// to be moving too fast when climbing hills :)
float height = 0;
Vector3 normal = Vector3.Up;
// Test to see if we reached the border of the ground.
if (Ground != null && !Ground.TryGetHeightAndNormal(Position, out height, out normal))
{
steerable.Position = currentPosition;
return;
}
// We don't want to make the entity moving too physically
// Moves the agent towards the target.
Vector3 facing = new Vector3(steerable.forward.X, 0, -steerable.forward.Y);
// Imagine we are climbing a hill
Vector3 right = Vector3.Cross(facing, normal);
Vector3 direction = Vector3.Cross(normal, right);
// Adjust player animation speed to avoid sliding artifact
float increment = Vector3.Dot(direction, facing);
steerable.Position = Vector2.Lerp(currentPosition, nextPosition, increment);
realHeight = height;
UpdateRotation(elapsedTime, facing);
Transform = Matrix.CreateFromAxisAngle(Vector3.Up, Rotation - MathHelper.PiOver2) *
Matrix.CreateTranslation(Position);
}