原理很简单，用点到直线的距离进行判断，没加回帧，所以如果加上碰撞反应，会有问题，代码如下：
import fc.math.Degree;
class Wall {
private var _wall:MovieClip;
private var _cenx:Number;
private var _ceny:Number;
private var _k:Number;
private var a1:Number;
private var b1:Number;
private var c1:Number;
public function Wall(w) {
_wall = w;
init();
}
public function get target():MovieClip {
return _wall;
}
private function init():Void {
_cenx = _wall._x;
_ceny = _wall._y;
_k = Degree.tanD(_wall._rotation);
a1 = -_k;
b1 = 1;
c1 = _k*_cenx-_ceny;
}
public function checkCollision(mc):Boolean {
var x0 = mc._x;
var y0 = mc._y;
var r = mc._width/2;
var t1 = a1*x0+b1*y0+c1;
var t2 = a1*a1+b1*b1;
return t1*t1/t2<r*r;
}
}
//test
import Wall;
var t1 = [new Wall(line1), new Wall(line2), new Wall(line3), new Wall(line4)];
setInterval(test, 30);
function test() {
for (var i in t1) {
var t = t1[i].checkCollision(mc);
if (t) {
t1[i].target.gotoAndStop(2);
} else {
t1[i].target.gotoAndStop(1);
}
}
}
拖动进行测试：