C# 如何使用角度进行拍摄？

坐着做一个2d射击游戏，我的玩家需要能够使用角度从左到右射击。我的问题是，我找不到一个办法使这项工作顺利进行

那么我如何计算以特定角度射出子弹的角度呢

我在player类中的代码

class Player
{
    //Player 
    public Rectangle playercollisionbox;
    public Texture2D Playertexture;
    public Vector2 Position = new Vector2(470, 850);



    //Bullet
    public Texture2D bulletTexture;
    //How fast you shoot
    public float bulletDelay = 1;
    public List<Bullet> bulletList;

    //Angle bullet
    public float spriterotation = 0;
    public float speed = 1;
    public Vector2 bulletposition;


    //Health
    public int Health;
    public Vector2 healthbarposition = new Vector2(20, 40);
    public Texture2D healthbartexture;
    public Rectangle healthrectangle;


    //Contructor
    public Player()
    {
        bulletList = new List<Bullet>();
        Health = 200;
    }

    public void LoadContent(ContentManager Content)
    {

        bulletTexture = Content.Load<Texture2D>(@"images/projectile2");
        healthbartexture = Content.Load<Texture2D>(@"images/HealthBar");




    }

    public void Update(GameTime gameTime)
    {


        KeyboardState keyboardState = Keyboard.GetState();

        playercollisionbox = new Rectangle((int)Position.X, (int)Position.Y, Playertexture.Width, Playertexture.Height); 
        //Player movement
        if (keyboardState.IsKeyDown(Keys.Up))
        {
            Position.Y -= 7;
        }

        if (keyboardState.IsKeyDown(Keys.Left))
        {
            Position.X -= 7;
        }
        if (keyboardState.IsKeyDown(Keys.Down))
        {
            Position.Y += 7;
        }
        if (keyboardState.IsKeyDown(Keys.Right))
        {
            Position.X += 7;
        }
        //Player movement

        healthrectangle = new Rectangle((int)healthbarposition.X, (int)healthbarposition.Y, Health, 25);

        //Off-screen block
        if (Position.X < 0)
        {
            Position.X = 0;
        }
        if (Position.Y < 0)
        {
            Position.Y = 0;
        }
        if (Position.X > 943)
        {
            Position.X = 943;
        }
        if (Position.Y > 904)
        {
            Position.Y = 904;
        }

        //Bullet
        if (keyboardState.IsKeyDown(Keys.Space))
        {
            Shoot();
        }
        UpdateBullet();

    }

    public virtual void Draw(SpriteBatch spriteBatch)
    {

        spriteBatch.Draw(Playertexture, Position, Color.White);
        foreach (Bullet b in bulletList)
        {
            b.Draw(spriteBatch);
        }
        spriteBatch.Draw(healthbartexture, healthrectangle, Color.White);
    }
    //Shooting method 
    public void Shoot()
    {
        if (bulletDelay >= 0)
        {
            bulletDelay--;
        }
        if (bulletDelay <= 0)
        {
            //First Bullet
            Bullet newBullet = new Bullet(bulletTexture);
            newBullet.position = new Vector2(Position.X + 40 - newBullet.texture.Width / 2, Position.Y - 40);
            newBullet.isVisible = true;
            //Second Bullet





            if (bulletDelay == 0)
            {
                bulletDelay = 20;
            }

            if (bulletList.Count() < 20)
            {
                bulletList.Add(newBullet); 
            }


        }
    }
    //Updating bullet after shooting
    public void UpdateBullet()
    {
        //speed on nullet
        foreach (Bullet b in bulletList)
        {

            b.position.Y = b.position.Y - b.speed;
            b.bulletcollisionbox = new Rectangle((int)b.position.X, (int)b.position.Y, b.texture.Width, b.texture.Height);

            //outside screen removes it
            if (b.position.Y <= 0)
            {
                b.isVisible = false;
            }
        }

        for (int i = 0; i < bulletList.Count; i++)
          {
              if (!bulletList[i].isVisible)
              {
                  bulletList.RemoveAt(i);
                  i--;
              }
          }

    }

 }

---

实际上，我有一个自制的小库，我在我所有的XNA项目中都使用它。助手函数之一是：

/// <summary>
/// Converts a given angle into a Vector2.
/// </summary>
/// <param name="angle">The angle (in radians).</param>
/// <param name="normalize">True to normalize the resultant vector, otherwise false.</param>
/// <returns>A vector representing the specified angle.</returns>
public static Vector2 Vector2FromAngle(double angle, bool normalize = true)
{
    Vector2 vector = new Vector2((float)Math.Cos(angle), (float)Math.Sin(angle));
    if (vector != Vector2.Zero && normalize)
        vector.Normalize();
    return vector;
}

//
///将给定角度转换为矢量2。
/// 
///角度（弧度）。
///True以规范化结果向量，否则为false。
///表示指定角度的向量。
公共静态向量2向量2Fromangle（双角度，布尔规格化=真）
{
vector2vector=新的Vector2（（float）Math.Cos（angle），（float）Math.Sin（angle））；
if（vector！=Vector2.Zero&&normalize）
vector.Normalize（）；
返回向量；
}

请随意使用它！它返回的向量就是子弹的轨迹

---

如果您不熟悉如何将度转换为弧度，

radians=degrees*pi/180

以及如何将角度转换回

degrees=radians*180/pi

弧度中两个向量之间的角度

Math.Atan2(b.Y - a.Y,b.X - a.X);

子弹方向

Vector2 direction = playerPosition - enemyPosition;
direction.Normalize();

---

然后通过方向向量增加子弹位置

Hi！谢谢你的回答。我不明白的是，我会替换“角度”而不是位置吗？不要真的找到放置角度的地方，让子弹找到那个位置。如果你能再描述一下我是如何做到这一点的，那就太好了。这里是使用角度吗？“newBullet.position=newvector2（position.X+40-newBullet.texture.Width/2，position.Y-40）；”您还可以使用

MathHelper.ToRadians

进行转换，反之亦然

position+=newNormalizedVector*速度

Vector2 direction = playerPosition - enemyPosition;
direction.Normalize();