1 package 2 { 3 import flash.display.BitmapData; 4 import flash.display.BlendMode; 5 import flash.display.DisplayObject; 6 import flash.display.Sprite; 7 import flash.geom.ColorTransform; 8 import flash.geom.Matrix; 9 import flash.geom.Point; 10 import flash.geom.Rectangle; 11 12 public class HitTest 13 { 14 /** 15 * 碰撞检测 16 * @param target1 17 * @param target2 18 * @param accurracy 19 * @return 20 */ 21 public static function complexHitTestObject( target1:DisplayObject, target2:DisplayObject, accurracy:Number = 1 ):Boolean 22 { 23 return complexIntersectionRectangle( target1, target2, accurracy ).width != 0; 24 } 25 /** 26 * 27 * @param target1 28 * @param target2 29 * @return 30 */ 31 public static function intersectionRectangle( target1:DisplayObject, target2:DisplayObject ):Rectangle 32 { 33 // If either of the items don't have a reference to stage, then they are not in a display list 34 // or if a simple hitTestObject is false, they cannot be intersecting. 35 if( !target1.root || !target2.root || !target1.hitTestObject( target2 ) ) return new Rectangle(); 36 // Get the bounds of each DisplayObject. 37 var bounds1:Rectangle = target1.getBounds( target1.root ); 38 var bounds2:Rectangle = target2.getBounds( target2.root ); 39 // Determine test area boundaries. 40 var intersection:Rectangle = new Rectangle(); 41 intersection.x = Math.max( bounds1.x, bounds2.x ); 42 intersection.y = Math.max( bounds1.y, bounds2.y ); 43 intersection.width = Math.min( ( bounds1.x + bounds1.width ) - intersection.x, ( bounds2.x + bounds2.width ) - intersection.x ); 44 intersection.height = Math.min( ( bounds1.y + bounds1.height ) - intersection.y, ( bounds2.y + bounds2.height ) - intersection.y ); 45 return intersection; 46 } 47 /** 48 * 49 * @param target1 50 * @param target2 51 * @param accurracy 52 * @return 53 */ 54 public static function complexIntersectionRectangle( target1:DisplayObject, target2:DisplayObject, accurracy:Number = 1 ):Rectangle 55 { 56 if( accurracy <= 0 ) throw new Error( "ArgumentError: Error #5001: Invalid value for accurracy", 5001 ); 57 // If a simple hitTestObject is false, they cannot be intersecting. 58 if( !target1.hitTestObject( target2 ) ) return new Rectangle(); 59 var hitRectangle:Rectangle = intersectionRectangle( target1, target2 ); 60 // If their boundaries are no interesecting, they cannot be intersecting. 61 if( hitRectangle.width * accurracy <1 || hitRectangle.height * accurracy <1 ) return new Rectangle(); 62 var bitmapData:BitmapData = new BitmapData( hitRectangle.width * accurracy, hitRectangle.height * accurracy, false, 0x000000 ); 63 // Draw the first target. 64 bitmapData.draw( target1, HitTest.getDrawMatrix( target1, hitRectangle, accurracy ), new ColorTransform( 1, 1, 1, 1, 255, -255, -255, 255 ) ); 65 // Overlay the second target. 66 bitmapData.draw( target2, HitTest.getDrawMatrix( target2, hitRectangle, accurracy ), new ColorTransform( 1, 1, 1, 1, 255, 255, 255, 255 ), BlendMode.DIFFERENCE ); 67 // Find the intersection. 68 var intersection:Rectangle = bitmapData.getColorBoundsRect( 0xFFFFFFFF,0xFF00FFFF ); 69 bitmapData.dispose(); 70 // Alter width and positions to compensate for accurracy 71 if( accurracy != 1 ) 72 { 73 intersection.x /= accurracy; 74 intersection.y /= accurracy; 75 intersection.width /= accurracy; 76 intersection.height /= accurracy; 77 } 78 intersection.x += hitRectangle.x; 79 intersection.y += hitRectangle.y; 80 return intersection; 81 } 82 /** 83 * 84 * @param target 85 * @param hitRectangle 86 * @param accurracy 87 * @return 88 */ 89 protected static function getDrawMatrix( target:DisplayObject, hitRectangle:Rectangle, accurracy:Number ):Matrix 90 { 91 var localToGlobal:Point;; 92 var matrix:Matrix; 93 var rootConcatenatedMatrix:Matrix = target.root.transform.concatenatedMatrix; 94 localToGlobal = target.localToGlobal( new Point( ) ); 95 matrix = target.transform.concatenatedMatrix; 96 matrix.tx = localToGlobal.x - hitRectangle.x; 97 matrix.ty = localToGlobal.y - hitRectangle.y; 98 matrix.a = matrix.a / rootConcatenatedMatrix.a; 99 matrix.d = matrix.d / rootConcatenatedMatrix.d; 100 if( accurracy != 1 ) matrix.scale( accurracy, accurracy ); 101 return matrix; 102 } 103 } 104 }