/// <summary>
/// Update the enemy's movement
/// </summary>
/// <param name="gameTime">A representation of the time since the last update</param>
public void UpdateMovement(GameTime gameTime)
{
float relitiveX = World.player.position.X + World.player.offset.X - position.X;
float relitiveY = World.player.position.Y + World.player.offset.Y - position.Y;
float relitiveMagnitude = (float)Math.Sqrt(Math.Pow(relitiveX, 2) + Math.Pow(relitiveY, 2));
float tanDirection = MathHelper.ToDegrees((float)Math.Atan(relitiveY / relitiveX));
PlayerDirection = relitiveX < 0 ? tanDirection + 180 : tanDirection;
float timeDeltaMultiplier = (float)((double)gameTime.ElapsedGameTime.TotalSeconds * (double)Constants.TIMEDELTACONSTANT);
if (FollowPlayer && FollowingPlayer)
{
turnCounter = 0;
turnTime = 0;
turnRate = 0;
breakTime = 0;
breakTimer = 0;
if (direction < PlayerDirection)
{
direction += timeDeltaMultiplier;
}
else if (direction > PlayerDirection)
{
direction -= timeDeltaMultiplier;
}
if (relitiveMagnitude < 75)
{
FollowingPlayer = false;
turnCounter = 0;
turnTime = 1;
turnRate = World.random.Next(0, 2) == 0 ? -1 : 1;
breakTime = turnTime + World.random.Next(2, 6);
}
}
else if (FollowPlayer && !FollowingPlayer)
{
FollowingPlayer = breakTimer > breakTime;
if (turnCounter < 2)
{
direction += turnRate * timeDeltaMultiplier;
}
turnCounter += gameTime.ElapsedGameTime.TotalSeconds;
breakTimer += gameTime.ElapsedGameTime.TotalSeconds;
}
position.X += (float)(Velocity * timeDeltaMultiplier * Math.Cos(MathHelper.ToRadians(direction)));
position.Y += (float)(Velocity * timeDeltaMultiplier * Math.Sin(MathHelper.ToRadians(direction)));
drawPosition = position + offset;
drawDirection = direction + 90;
rotatedRectangle = new RotatedRectangle(CollisionRectangle, MathHelper.ToRadians(drawDirection));
}
/// <summary>
/// Construct the enemy
/// </summary>
/// <param name="sprite">The sprite to render</param>
/// <param name="startPos">The initial position of the enemy</param>
/// <param name="followPlayer">If the enemy should follow the player</param>
/// <param name="health">The maximum health of the player</param>
/// <param name="velocity">The maximum velocity of the player</param>
public Enemy(SpriteSheet.Sprite sprite, Vector2 startPos, bool followPlayer, int health, float velocity) : base(sprite, startPos, 0)
{
FollowingPlayer = FollowPlayer = followPlayer;
Explosions = new Explosion[2];
for (int i = 0; i < Explosions.Length; i++)
{
Explosions[i] = new Explosion(SpriteSheet.ExplosionSprites);
}
Lasers = new Laser[10];
for (int i = 0; i < Lasers.Length; i++)
{
Lasers[i] = new Laser(SpriteSheet.Sprite.LaserRed, 6f);
}
Health = health;
doUpdate = true;
Velocity = velocity;
PlayerDirection = 0;
Alive = true;
rotatedRectangle = new RotatedRectangle(CollisionRectangle, MathHelper.ToRadians(drawDirection));
}
public void Update(GameTime gameTime)
{
if (Keyboard.GetState().IsKeyDown(Keys.P) && debugSwitch)
{
debugPositions ^= true; debugSwitch = false;
}
else if (!Keyboard.GetState().IsKeyDown(Keys.P))
{
debugSwitch = true;
}
if (0 == flickerCount++)
{
Stars[random.Next(Stars.Count)].doDraw ^= true;
}
flickerCount %= 20;
foreach (Entity entity in Entities)
{
entity.Update(gameTime);
}
if (debugPositions)
{
int currentIndex = 0;
for (int i = 0; i < player.CollisionPoints.Length; i++)
{
hitPointVisuals[currentIndex].coordinates = player.CollisionPoints[currentIndex++];
}
hitPointVisuals[currentIndex++].coordinates = player.position;
for (int i = 0; i < enemies.Length; i++)
{
RotatedRectangle newRectangle = (enemies[i].rotatedRectangle + enemies[i].position);
hitPointVisuals[currentIndex++].coordinates = newRectangle.TopLeft;
hitPointVisuals[currentIndex++].coordinates = newRectangle.TopRight;
hitPointVisuals[currentIndex++].coordinates = newRectangle.BottomLeft;
hitPointVisuals[currentIndex++].coordinates = newRectangle.BottomRight;
}
}
CollisionDetection();
}
public bool Intersects(RotatedRectangle rectangle)
{
return(false);
}