as3打造过点作已知直线的垂线,求垂足坐标

var Arr:Array=new Array();
Arr.push({m_type:null});//0
Arr.push({m_type:"point",m_x:100,m_y:100});//1
Arr.push({m_type:"point",m_x:200,m_y:200});//2
Arr.push({m_type:"line2",m_p1:1,m_p2:2});   //3
Arr.push({m_type:"point",m_x:150,m_y:100});//4
//以上是一个点4和一条线3，求垂足坐标.
chuizu(4,3);
function chuizu(point:Number,line:Number){
var point_x:Number =Arr[point].m_x;
var point_y:Number =Arr[point].m_y;
var line_p1:Number =Arr[line].m_p1;
var line_p2:Number =Arr[line].m_p2;
var line_p1_x:Number =Arr[line_p1].m_x;
var line_p1_y:Number =Arr[line_p1].m_y;
var line_p2_x:Number =Arr[line_p2].m_x;
var line_p2_y:Number =Arr[line_p2].m_y;
var line_k1:Number =(line_p2_y-line_p1_y)/(line_p2_x-line_p1_x);
var line_b1:Number =line_p1_y-line_k1*line_p1_x;
var line_k2:Number =-1/line_k1;
var line_b2:Number =point_y-line_k2*point_x;
var node_x:Number =(line_b1-line_b2)/(line_k2-line_k1);
var node_y:Number =(line_k2*line_b1-line_k1*line_b2)/(line_k2-line_k1);
trace(node_x,node_y);
}
本文转自：http://www.5uflash.com/flashjiaocheng/Flash-as3-jiaocheng/1949.html