public void AddEnemy()
{
if (CharPool.Count == 0)
{
gameLevel.levelUp();
TheForm.TimerCreateLetter.Interval = gameLevel.ENEMY_APPEAR;
TheForm.TimerMoveEnemies.Interval = gameLevel.ENEMY_SPEED;
generatePool();
}
int i = random.Next(0, CharPool.Count);
Char selected = CharPool[i];
CharPool.RemoveAt(i);
Enemy enemy = new Enemy(TheForm, findValidSpawn(), selected);
Enemies.Add(enemy);
TheForm.GetControls().Add(enemy);
}
private void DrawStrike(Enemy res)
{
Canon cannon = CannonToShot(res);
Graphics graphics = TheForm.CreateGraphics();
Point[] points = { new Point(cannon.Left + cannon.Width/2 - 8, cannon.Top), new Point(cannon.Left + cannon.Width/2 + 8, cannon.Top), new Point(res.Left + res.Width / 2 + 5, res.Top + res.Height / 2),
new Point(res.Left + res.Width / 2 - 5, res.Top + res.Height / 2)};
PathGradientBrush brush = new PathGradientBrush(points);
brush.CenterPoint = new Point(cannon.Left + cannon.Width / 2, cannon.Top);
brush.CenterColor = Color.DarkBlue;
brush.SurroundColors = new[] { Color.White, Color.Violet};
FillMode fillMode = FillMode.Winding;
graphics.FillPolygon(brush, points, fillMode);
TimerStrike.Start();
}
private Canon ClosestCannon(Enemy enemy)
{
int min = int.MaxValue;
Canon minCannon = null;
foreach (Canon cannon in Cannons)
{
if (Math.Abs(cannon.Left - enemy.Left) < min)
{
min = Math.Abs(cannon.Left - enemy.Left);
minCannon = cannon;
}
}
return minCannon;
}
private bool CanonIsHit(Enemy enemy)
{
if (Cannons.Count > 0)
return enemy.Top + enemy.Height >= Cannons[0].Top;
else
return false;
}
private Canon CannonToShot(Enemy enemy)
{
if (enemy.Left <= TheForm.Width / 3)
return Cannons[random.Next(Cannons.Count == 1 ? 0 : 1, Cannons.Count)];
else if (enemy.Left > 2 / 3 * TheForm.Width)
return Cannons[random.Next(0, Cannons.Count - 1)];
else
return Cannons[random.Next(0, Cannons.Count)];
}
/// <summary>
/// Checks if the spawn position does not overlap with the other letter
/// </summary>
/// <param name="left">Left coordinate for the test enemy</param>
/// <param name="enemy">Position of the already spawned enemy</param>
/// <returns>True if invalid position, false otherwise</returns>
private static bool checkInvalidSpawn(int left, Enemy enemy)
{
return ((left >= enemy.Left) && (left <= (enemy.Left + enemy.Width)) ||
(left <= enemy.Left) && (left >= (enemy.Left - enemy.Width))) && (enemy.Top <= ( enemy.Height + 56));
}