// forked from JuanSierra's flash on 2009-4-21
package {
    import flash.display.Sprite;
    import flash.events.*;    
    import flash.display.*;
    import flash.text.*;
    import flash.events.*;
    import flash.display.Sprite; 
    import flash.display.StageAlign; 
    import flash.display.StageScaleMode;

[SWF(backgroundColor="0x333333", frameRate="30")]

public class FlashTest extends Sprite
    {
        private var beam:Sprite = new Sprite();
        private var a:Number=0.08;
        private var v:Number=0.05;
    
        
        public function FlashTest() {
            var anchoBeam:int = 100;
            var numLineas:int = 5;
            
            for(var i:int=0; i<numLineas; i++)
            {
                beam.graphics.lineStyle(1,0xff0000);  
                beam.graphics.moveTo((anchoBeam/numLineas)*i,0);  
                beam.graphics.lineTo((anchoBeam/numLineas)*i, 40); 
            }
            addChild(beam);
            beam.x=100;
            addEventListener(Event.ENTER_FRAME,pintar);
        }

private function pintar(event:Event):void
        {
            if(beam.y<400)
            {
                v+=a;
                beam.y+=v;
                beam.x=5*Math.sin(beam.y); 
            }
        }
    }
 }
     class HitTest {
          import flash.display.DisplayObject;
          import flash.display.BitmapData;
          import flash.geom.ColorTransform;
          import flash.geom.Matrix;
          import flash.geom.Rectangle;
          
          /**
           * hitTestObject checks to see if two display objects have collided from
           * http://www.adventuresinactionscript.com/blog/15032008/actionscript-3-hit...
           * Based on Grant Skinner & Troy Gilberts collision detection functions
           *
           * @param  object1      the first object to be tested
           * @param  object2      the second object to be tested
           * @param  pixelPerfect check bounding rectangle only if set to false
           * @param  tolerance    alpha tolerance value
           * @return intersecting rectangle if the objects have collided, or null if no collision
           * @see         hitTestObject
           */ 
          static public function hitTestObject(object1:DisplayObject, object2:DisplayObject, pixelPerfect:Boolean=true, tolerance:int = 255):Rectangle {
               
               // quickly rule out anything that isn't in our hitregion
               if (object1.hitTestObject(object2)) {
               
                    // get bounds:
                    var bounds1:Rectangle = object1.getBounds(object1.parent);
                    var bounds2:Rectangle = object2.getBounds(object2.parent);
                                   
                    // determine test area boundaries:
                    var bounds:Rectangle = bounds1.intersection(bounds2);
                    bounds.x = Math.floor(bounds.x);
                    bounds.y = Math.floor(bounds.y);
                    bounds.width = Math.ceil(bounds.width);
                    bounds.height = Math.ceil(bounds.height);
                              
                    //ignore collisions smaller than 1 pixel
                    if ((bounds.width < 1) || (bounds.height < 1))
                         return null;
                         
                    if (!pixelPerfect)
                         return bounds;
               
                    // set up the image to use:
                    var img:BitmapData = new BitmapData(bounds.width, bounds.height, false);
                    
                    // draw in the first image:
                    var mat:Matrix = object1.transform.concatenatedMatrix;
                    mat.translate( -bounds.left, -bounds.top);
                    img.draw(object1,mat, new ColorTransform(1,1,1,1,255,-255,-255,tolerance));
                    
                    // overlay the second image:
                    mat = object2.transform.concatenatedMatrix;
                    mat.translate( -bounds.left, -bounds.top);
                    img.draw(object2,mat, new ColorTransform(1,1,1,1,255,255,255,tolerance),"difference");
                    
                    // find the intersection:
                    var intersection:Rectangle = img.getColorBoundsRect(0xFFFFFFFF,0xFF00FFFF);
                    
                    // if there is no intersection, return null:
                    if (intersection.width == 0) { return null; }
                    
                    // adjust the intersection to account for the bounds:
                    intersection.offset(bounds.left, bounds.top);
                    
                    return intersection;
               }
               else
                    return null;
          }         
          
     }

forked from: flash on 2009-4-21