在光标处拍摄子弹Flash AS3

Question

我正在使用AS3制作闪光灯的自上而下射击游戏，并且在从WASD键向光标移动的船上发射子弹时遇到了一些问题。子弹创建的不错，但它们随机方向而不是指向按下空间时光标所在的位置。

这是子弹类的代码：

package{ 
import flash.display.MovieClip; 
import flash.events.Event; 
import flash.ui.Mouse; 
import flash.events.MouseEvent; 
import flash.geom.Point; 

public class Bullet extends MovieClip 
{ 
    var speed:Number; 
    var moveX:Number; 
    var moveY:Number; 
    var shipX:Number; 
    var shipY:Number; 

    function Bullet(target:Ship) 
    { 
     speed = 20; 
     shipX = target.x; 
     shipY = target.y; 

     graphics.lineStyle(7,0x000000); 
     graphics.moveTo(-2,0); 
     graphics.lineTo(2,0); 

     graphics.lineStyle(3,0xffffff); 
     graphics.moveTo(-2,0); 
     graphics.lineTo(2,0); 

     addEventListener(Event.ADDED_TO_STAGE, onStage); 

    } 

    function onStage (e:Event) 
    { 
     /*addEventListener("enterFrame", enterFrame); 

     /*var mc = 
     var angleRadian = Math.atan2(mouseY - mc.y, mouseX - mc.x); 
     var angleDegree = angleRadian * 180/Math.PI; 
     mc.rotation = angleDegree;*/ 

     /*Ship.y += speed * Math.sin((Ship.rotation - 90) * (Math.PI/180)); 
     Ship.x += speed * Math.cos((Ship.rotation - 90) * (Math.PI/180));*/ 



     trace(stage.mouseY); 
     var cy:Number = stage.mouseY - shipY; 
     var cx:Number = stage.mouseX - shipX; 

     moveX = cx/cy; 
     moveY = (cy < 0) ? -1 : 1; 
     var Radians:Number = Math.atan2(cy,cx); 
     var Degrees:Number = Radians * 180/Math.PI;*/ 
    } 
    function enterFrame(e:Event) 
    { 
     /*this.x += speed;*/ 

     this.x += moveX * speed; 
     this.y += moveY * speed; 



     if (this.x > 900) 
     { 
      removeEventListener("enterFrame",enterFrame); 
      stage.removeChild(this); 
     } 
     if (this.x < 0) 
     { 
      removeEventListener("enterFrame",enterFrame); 
      stage.removeChild(this); 
     } 
     if (this.y > 800) 
     { 
      removeEventListener("enterFrame",enterFrame); 
      stage.removeChild(this); 
     } 
     if (this.y < 0) 
     { 
      removeEventListener("enterFrame",enterFrame); 
      stage.removeChild(this); 
     } 

     for(var i in Enemy.list) 
      { 
       if(this.hitTestObject(Enemy.list[i])) 
       { 
        removeEventListener("enterFrame", enterFrame); 
        stage.removeChild(this); 
        Enemy.list[i].kill(); 
        break; 
       } 
      } 
    } 
} 

}

任何让子弹妥善火的帮助，将不胜感激！

Answer 1

x和y速度应分别是角度的cos和sin（弧度）的结果。

即

var angle:Number = Math.atan2(cy, cx); 
moveX = Math.cos(angle); 
moveY = Math.sin(angle); 

然后通过速度（这你已经做）乘这两种。

而且，你不需要计算度，除非你要旋转的图形：

rotation = angle * 180/Math.PI;