private static Single CalculateRotation(Single rotation, Single gamePadLeftX, Single gamePadLeftY, Boolean turnLeft, Boolean turnRight)
{
if (gamePadLeftX >= TURN_AXIS_DEADBAND || gamePadLeftX <= -TURN_AXIS_DEADBAND || gamePadLeftY >= TURN_AXIS_DEADBAND || gamePadLeftY <= -TURN_AXIS_DEADBAND)
{
Single desiredRotation = FloatMathHelper.Atan2(gamePadLeftY, gamePadLeftX);
if (Math.Abs(rotation - desiredRotation) < TOP_TURN_SPEED)
{
rotation = desiredRotation;
}
else
{
if (FloatMathHelper.CounterClockwiseAngularDistance(rotation, desiredRotation) < FloatMathHelper.ClockwiseAngularDistance(rotation, desiredRotation))
{
rotation -= TOP_TURN_SPEED;
}
else
{
rotation += TOP_TURN_SPEED;
}
}
}
else
{
if (turnLeft)
{
rotation -= TOP_TURN_SPEED * 0.5f;
}
else if (turnRight)
{
rotation += TOP_TURN_SPEED * 0.5f;
}
}
return(MathHelper.WrapAngle(rotation));
}
private static Single CalculateRotation(Single currentRotation, Vector2 rotationVector, Single topTurningSpeed)
{
rotationVector.Normalize();
Single desiredRotation = FloatMathHelper.Atan2(rotationVector.Y, rotationVector.X);
if (Math.Abs(currentRotation - desiredRotation) < topTurningSpeed)
{
currentRotation = desiredRotation;
}
else
{
if (FloatMathHelper.CounterClockwiseAngularDistance(currentRotation, desiredRotation) < FloatMathHelper.ClockwiseAngularDistance(currentRotation, desiredRotation))
{
currentRotation -= topTurningSpeed;
}
else
{
currentRotation += topTurningSpeed;
}
}
return(MathHelper.WrapAngle(currentRotation));
}
/// <summary>
/// Calculate the angular distance from r to R in a clockwise direction
/// </summary>
/// <param name="r">First angle in Radians</param>
/// <param name="R">First angle in Radians</param>
/// <returns>Distance in Radians</returns>
public static Single ClockwiseAngularDistance(Single r, Single R)
{
return(MathHelper.TwoPi - FloatMathHelper.CounterClockwiseAngularDistance(r, R));
}
public override void Update(GameTime gameTime)
{
if (this.Alive)
{
Vector2 homingPosition = this.Game.SurvivorSubsystem.PlayerOneSurvivorSprite.Location.Position;
Vector2 oldPosition = Location.Position;
Single oldRotation = Location.Rotation;
Single currentRotation = Location.Rotation;
Vector2 currentPosition = Location.Position;
Vector2 deltaPosition = homingPosition - currentPosition;
Single rotation = CalculateRotation(currentRotation, deltaPosition, TopTurningSpeed());
Vector2 velocityVector = new Vector2(FloatMathHelper.Cos(rotation), FloatMathHelper.Sin(rotation));
if (Math.Abs(deltaPosition.Length()) > TopMovementSpeed())
{
Single speed = 0.0f;
Single cwAngularDistance = FloatMathHelper.ClockwiseAngularDistance(currentRotation, rotation);
Single ccwAngularDistance = FloatMathHelper.CounterClockwiseAngularDistance(currentRotation, rotation);
Single deltaRotation = MathHelper.Min(cwAngularDistance, ccwAngularDistance);
if (deltaRotation <= TURNING_MOVEMENT_LIMIT)
{
speed = TopMovementSpeed() * ((TURNING_MOVEMENT_LIMIT - deltaRotation) / TURNING_MOVEMENT_LIMIT);
}
Location.Position += (velocityVector * speed);
Location.Rotation = rotation;
if (Game.SurvivorSubsystem.SurvivorsCollisionManager.CheckForCollisionsWith(this) || Game.ZombiesSubsystem.ZombiesCollisionManager.CheckForCollisionsWith(this))
{
Location.Position = oldPosition;
Location.Rotation = oldRotation;
zombieStationaryTime += gameTime.ElapsedGameTime.TotalSeconds;
}
else
{
zombieStationaryTime = 0.0;
}
}
if (zombieStationaryTime >= ZOMBIE_MAXIMUM_STATIONARY_TIME)
{
Alive = false;
}
Single zombieAttackValue = 0.0f;
if (zombieAttackTime >= ZOMBIE_ATTACK_DELAY_TIME[(int)Game.Options.GameDifficulty])
{
zombieAttackValue = ZOMBIE_ATTACK_VALUE;
}
if (Game.SurvivorSubsystem.SurvivorsAttackManager.AttackWithMelee(this, zombieAttackValue) == AttackResults.Damage)
{
zombieAttackTime += gameTime.ElapsedGameTime.TotalSeconds;
}
else
{
zombieAttackTime = 0.0;
}
if (animating)
{
zombieAnimationTime += gameTime.ElapsedGameTime.TotalSeconds;
if (zombieAnimationTime >= ANIMATION_DELAY)
{
animationIndex++;
if (animationIndex < ANIMATION_CELL_INDICIES.Length)
{
currentCellIndex = ANIMATION_CELL_INDICIES[animationIndex];
zombieAnimationTime = 0.0;
}
else
{
currentCellIndex = 0;
animating = false;
}
}
}
}
}