public override void Update(double elapsedTime)
{
if (!working)
{
if (disposing)
{
if (disposingTime > 0)
{
angle += (float)elapsedTime * 360 * 3;
_alpha = disposingTime / 12.0f;
disposingTime--; //注销计时-1
}
else
{
disposing = false;
disabled = true; //在最后的旋转特效以后，同意注销此子弹
}
}
return;
}
speed += 2; //每帧速度+1
if (Datas.CurrentEnemys.Count > 0)
{
double distance = 100000000; //取一个极端数值，使每一个求得值都会小于这个值
double lastdistance = distance;
foreach (Enemy e in Datas.CurrentEnemys) //将离Player距离最短的作为跟踪对象
{
if (e.Position.X < -200 || e.Position.X > 200 || e.Position.Y < -40 || e.Position.Y > 500)
continue;
distance = (Datas.CurrentPlayer.Position.X - e.Position.X) * (Datas.CurrentPlayer.Position.X - e.Position.X) +
(Datas.CurrentPlayer.Position.Y - e.Position.Y) * (Datas.CurrentPlayer.Position.Y - e.Position.Y);
if (distance < lastdistance)
{
FollowEnemy = e;
}
lastdistance = distance;
}
}
if (Position.X < -190 || Position.X > 190 || Position.Y < -20 || Position.Y > 450)
{
speed = 0;
working = false;
disabled = true;
}
move(elapsedTime);
//跟踪旋转
if (FollowEnemy != null && !FollowEnemy.disabled && FollowEnemy.living)
{
Vector2D vct = new Vector2D(FollowEnemy.Position.X - Position.X,
FollowEnemy.Position.Y - Position.Y);
if (!(vct.X == 0 && vct.Y == 0))
{
double distance = vct.X * vct.X + vct.Y * vct.Y;
double percent = distance / 40000;
if (percent > 1)
percent = 1;
percent = 1 - percent;
float addangle = (float)percent * 1080;
vct.Normalize();
double vct_angle = vct.GetAngle(); //目标的角度值
double dir_angle = Direction.GetAngle(); //当前方向的角度值
if (vct_angle < dir_angle)
{
if (dir_angle - vct_angle < 180)
{
Direction.rotate( (addangle + rotateSpeed) * (float)elapsedTime);
double d_2 = Direction.GetAngle();
if (d_2 > dir_angle) //如果左旋转后反而比原本角度更大，则证明旋转过度
{
Direction.X = vct.X;
Direction.Y = vct.Y;
}
else if (d_2 < vct_angle) //如果旋转后跑到方向角左边，则证明旋转过度
{
Direction.X = vct.X;
Direction.Y = vct.Y;
}
}
else
{
Direction.rotate((- addangle -rotateSpeed) * (float)elapsedTime);
double d_2 = Direction.GetAngle();
if (d_2 < dir_angle) //如果旋转后反而比原本角度更小，则证明旋转过了一周
{
if (d_2 > vct_angle)
{
Direction.X = vct.X;
Direction.Y = vct.Y;
}
}
}
}
else if (vct_angle > dir_angle)
{
if (vct_angle - dir_angle < 180)
{
Direction.rotate((-addangle -rotateSpeed) * (float)elapsedTime);
double d_2 = Direction.GetAngle();
if (d_2 < dir_angle)
{
Direction.X = vct.X;
Direction.Y = vct.Y;
}
else if (d_2 > vct_angle)
{
Direction.X = vct.X;
Direction.Y = vct.Y;
}
}
else
{
Direction.rotate((addangle + rotateSpeed) * (float)elapsedTime);
double d_2 = Direction.GetAngle();
if (d_2 > dir_angle)
{
if (d_2 < vct_angle)
{
Direction.X = vct.X;
Direction.Y = vct.Y;
}
}
}
}
}
}
}
/// <summary>
/// 对敌人的技能判定
/// </summary>
/// <param name="e">判定的敌人对象</param>
/// <param name="msg">返回的判定信息</param>
/// <returns>是否进入判定域</returns>
public virtual bool AttackCollision(Enemy e, ref MessageManager msg)
{
return false;
}