車子的移動

max = 10;
speed = 0;

onEnterFrame = function() {
   with(car) {
                      posX = Math.cos (angle);    //這裡的圓的計算可以參考flash8的教學
                      posY = Math.sin (angle);
                     
                      if (Key.isDown(key.left) && speed != 0) degree -= 5;    //按左鍵角度-5
                      if (Key.isDown(key.right) && speed != 0)degree += 5;
                      if (Key.isDown(key.up) && speed < max) speed += 0.8;    //按向上鍵速度增加
                      if (Key.isDown(key.down) && speed > -max) speed -= 0.4;    //因為退車速度會比較慢
                     
                      _x += posX * speed;    //設定車子的x和y, 當然重要的步驟是以上的posX和posY, 還有下方的弧度計算
                      _y += posY * speed;
                      _rotation = degree;
                     
                      if ( speed > 0 ) speed -= 0.25;
      if ( speed < 0 ) speed += 0.25;      
                     
                      angle = (degree*(Math.PI/180));
   }
}