flash on 2012-11-9

by mutantleg 09 Nov 2012

Embed

/**
 * Copyright mutantleg ( http://wonderfl.net/user/mutantleg )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/2oTp
 */

package {
    import flash.text.TextField;
    import flash.events.Event;
    import flash.display.Sprite;
    public class FlashTest extends Sprite {
        

        
        public var deb:TextField;
        
        public function FlashTest() {
            
            deb = new TextField();
            addChild(deb);
            
            stage.addEventListener(Event.ENTER_FRAME, onEnter);
        }
        
        //based on 
        //http://clb.demon.fi/MathGeoLib/docs/Line.cpp_code.html

      
      public var dt:Number = 0;
      
      public function cpLineLine(      ax:Number, ay:Number,
      bx:Number, by:Number,
       cx:Number, cy:Number,
      dx:Number, dy:Number):Number
      {
          //ax 0
          //ay 0
          //bx 0
          //by 0
          
          var d0232:Number;
          var d3210:Number;
          var d3232:Number;
          var mu:Number;
          
          d0232 =  (ax - cx) * (dx-cx) + (ay - cy) * (dy - cy);
          d3210 =  (dx - cx) * (bx - ax) + (dy - cy) * (by - ay);
          d3232 =  (dx - cx) * (dx - cx) + (dy - cy) * (dy - cy);
          
          var d0210:Number;
          var d1010:Number;
         
          
          d0210 = (ax-cx) * (bx-ax) + (ay-cy) * (by - ay);
          d1010 = (bx-ax)*(bx-ax) + (by-ay) * (by-ay);
         
         mu = (d0232 * d3210 - d0210*d3232) / (d1010 * d3232 - d3210*d3210);
          
          dt = (d0232 + mu * d3210) / d3232;
          
          /*
          float mu = (d0232 * d3210 -
           Dmnop(v,0,2,1,0)*d3232) /
            (Dmnop(v,1,0,1,0)*Dmnop(v,3,2,3,2) -
             Dmnop(v,3,2,1,0)*Dmnop(v,3,2,1,0));
             */
          
  //           float d0232 = Dmnop(v,0,2,3,2);
 //        float d3210 = Dmnop(v,3,2,1,0);
  //       float d3232 = Dmnop(v,3,2,3,2);
       
       return mu;   
      }//cplineline
        
        public function onEnter(e:Event):void
        {
            var ax:Number = 50;
            var ay:Number = 90;
            var bx:Number = 120;
            var by:Number = 300;
            
            var cx:Number = 300;
            var cy:Number = 30;
            var dx:Number = 50;
            var dy:Number = 350;
            
            var t:Number;
            
          
            
            dx = mouseX;
            dy = mouseY;
                     
            t = cpLineLine(ax,ay,bx,by,cx,cy,dx,dy);
             
            
            graphics.clear();
            
            graphics.lineStyle(2,0);
            
            graphics.moveTo(ax,ay);
            graphics.lineTo(bx,by);
            
            graphics.moveTo(cx,cy);
            graphics.lineTo(dx,dy);
            
            
            var kx:Number;
            var ky:Number;
            
            if (t > 1) { t = 1;}
            if (t < 0) { t = 0;}
            
            kx = ax + (bx - ax) * t;
            ky = ay + (by - ay) * t;
            
            graphics.drawCircle(kx, ky, 16);
            
            var ux:Number;
            var uy:Number;
            var u:Number;
            
         
            u = lineCirc3(cx,cy,dx,dy,kx,ky,16);
            
          
            ux = cx + (dx - cx) * u;
            uy = cy + (dy - cy) * u;
            
         
            deb.text = "t " + t + " \n dt " + dt + " \n u " + u;
       
         
            
            graphics.drawCircle(ux, uy, 4);
            
            graphics.lineStyle(1,0);
            
            graphics.moveTo(kx,ky);
            graphics.lineTo(ux,uy);
            
            
        }//onenter
        
        
        //based on
        //http://www.geometrictools.com/SamplePhysics/CollisionsMovingSphereTriangle/RTSphereTriangle.cpp
        
        public function lineCirc3(
        ax:Number, ay:Number, bx:Number, by:Number,
        cx:Number, cy:Number, rad:Number):Number
        {
          
          var rsq:Number
          var vx:Number;
          var vy:Number;
          var mx:Number;
          var my:Number;
          var q2:Number;
          var q1:Number;
          var q0:Number;
          var disc:Number;
          
          rsq = rad * rad;
          
          mx = cx - ax;
          my = cy - ay;
          vx = ax - bx;
          vy = ay - by;
          
          q2 = (vx*vx +vy*vy);
          q1 = (vx*mx + vy*my);
          q0 = (mx*mx + my*my) - rsq;
          
          disc = q1*q1 - q0 * q2;
          
          if (disc < 0) { return 999; }
          
          var invq2:Number;
          var rootdisc:Number;
          var root0:Number;
          var root1:Number;
          
          invq2 = 1 / q2;
          rootdisc = Math.sqrt(disc);
          root0 = (-q1 - rootdisc) * invq2;
          root1 = (-q1 + rootdisc) * invq2;

          
          return root0;
        }//linecirc3
        
        
        
        
        
        
        
    }//classend
}