/// <summary>
/// Sets the new target building
/// </summary>
/// <param name="building"> Target building </param>
void setTargetBuilding(BuildingEntity building)
{
building.OnDeath += (a, b) =>
{
if (targetBuilding != null)
{
targetBuilding.Delete();
}
hasTarget = attacking = false;
};
targetBuilding = building;
}
/// <summary>
/// Update enemy logic
/// </summary>
public override void Update(GameTime gameTime)
{
// update animations
updateAnimations(gameTime);
float delta = (float)gameTime.ElapsedGameTime.TotalSeconds;
// if the enemy doesn't have a target and isn't entering,
// find a new target building
if (!isEntering && !hasTarget)
{
aquireNewTargetBuilding();
}
float speed = delta * walkSpeed;
// follow target path if the enemy isn't attacking
if (!attacking && path.Count > 1)
{
// get the position of our current target
var target = world.Grid[path[0]].Position +
properties.TargetNodeOffset;
// set our enemy walking
currentAnimation = "Walk";
shadowAnimation = "ShadowWalk";
if (Vector2.Distance(target, position) <= speed)
{
// we aren't entering anymore
isEntering = false;
path.RemoveAt(0);
// new node
var node = world.Grid[path[0]];
// new target position
var newTarget = node.Position +
properties.TargetNodeOffset;
if (node.Occupant != null &&
node.Occupant.BuildingType == Building.Barricade)
{
var tmpBuilding = targetBuilding;
targetBuilding = node.Occupant;
attacking = true;
targetBuilding.OnDeath += delegate
{
if (targetBuilding != null)
{
targetBuilding.Delete();
}
targetBuilding = tmpBuilding;
attacking = false;
hasTarget = true;
setTargetPosition(newTarget);
};
}
else
{
// set the new target position
setTargetPosition(newTarget);
}
// reached the destination, start attacking
if (path.Count == 1)
{
attacking = true;
// set our idle animation
currentAnimation = "Idle";
shadowAnimation = "ShadowIdle";
// set our idle animation frame to the frame
// prescribed by the building attack node
setIdleFrame(destinationFrame);
}
}
}
else if (attacking)
{
lastAttacked -= gameTime.ElapsedGameTime;
if (lastAttacked <= TimeSpan.Zero)
{
lastAttacked = attackInterval;
// attack the target building, we've reached our attack
// interval
attackTargetBuilding();
}
// make sure we're idle
velocity = Vector2.Zero;
}
// move the enemy based on our velocity
position += velocity * speed;
// update enemy bullet logic
checkBulletCollision();
}