A Little Metaball Action

And now for something completely different…

The other day, for reasons I can’t even explain to myself, I googled for metaball examples. No real need, I just rather like the way they look, all blobby and stuff. Well, one of the first things to come up was this nifty example in Java by Gordon Williams. I promptly decompiled the java and ported it all over to Actionscript 3. Afterwards I emailed the author and asked if it would be all right to publish the AS source, and he kindly said it would be fine (I know, I know, it’s a bit of an ass backward way to operate, but if he hadn’t been kind enough to say it was all right, you wouldn’t be reading this now).

So this is the result I got (double click the thing to get it going or stop it):

As you can, it’s currently (at least on my machine) running at around a craptacular 11 frames per second. If anyone would like to try their hand at optimizing the sucker please have at the code below (and please post your results here – I’d like to see what people come up with).

A couple supporting classes :

Vect.as

package {
	
	/**
	 * @author Gordon Williams (http://www.rabidhamster.org/index.php)
	 * 
	 * Java to Actionscript port by:
	 * @author Devon O. Wolfgang (http://blog.onebyonedesign.com)
	 */

	public class Vect {
		
		public var d:Vector.<Number> = new Vector.<Number>();

		public function Vect(paramFloat1:Number, paramFloat2:Number, paramFloat3:Number) {
			d.length = 4;
			d.fixed = true;
			d[0] = paramFloat1;
			d[1] = paramFloat2;
			d[2] = paramFloat3;
			d[3] = 1.0;
		}

		public function magnitude():Number {
			return Math.sqrt(d[0] * d[0] + d[1] * d[1] + d[2] * d[2]);
		}

		public function equal(paramVect:Vect):Boolean {
			return ((paramVect.d[0] == d[0]) && (paramVect.d[1] == this.d[1]) && (paramVect.d[2] == this.d[2]));
		}

		public function mul(paramFloat:Number):void {
			d[0] *= paramFloat;
			d[1] *= paramFloat;
			d[2] *= paramFloat;
		}

		public function div(paramFloat:Number):void {
			d[0] /= paramFloat;
			d[1] /= paramFloat;
			d[2] /= paramFloat;
		}

		public function add(paramVect:Vect):void {
			d[0] += paramVect.d[0];
			d[1] += paramVect.d[1];
			d[2] += paramVect.d[2];
		}

		public function sub(paramVect:Vect):void {
			d[0] -= paramVect.d[0];
			d[1] -= paramVect.d[1];
			d[2] -= paramVect.d[2];
		}

		public function dot(paramVect:Vect):Number {
			return (d[0] * paramVect.d[0] + d[1] * paramVect.d[1] + d[2] * paramVect.d[2]);
		}

		public function cross(paramVect:Vect):Vect {
			return new Vect(d[1] * paramVect.d[2] - (d[2] * paramVect.d[1]), d[2] * paramVect.d[0] - (d[0] * paramVect.d[2]), d[0] * paramVect.d[1] - (d[1] * paramVect.d[0]));
		}

		public function normalize():void {
			mul(1.0 / magnitude());
		}

		public function project():void {
			d[2] += 256.0;
			d[0] *= 1024.0 / d[2];
			d[1] *= 1024.0 / d[2];
		}

		public function copy():Vect {
			return new Vect(d[0], d[1], d[2]);
		}
	}
}

package {

/**

* @author Gordon Williams (http://www.rabidhamster.org/index.php)

* Java to Actionscript port by:

* @author Devon O. Wolfgang (http://blog.onebyonedesign.com)

public class Vect {

public var d:Vector.<Number> = new Vector.<Number>();

public function Vect(paramFloat1:Number, paramFloat2:Number, paramFloat3:Number) {

d.length = 4;

d.fixed = true;

d[0] = paramFloat1;

d[1] = paramFloat2;

d[2] = paramFloat3;

d[3] = 1.0;

}

public function magnitude():Number {

return Math.sqrt(d[0] * d[0] + d[1] * d[1] + d[2] * d[2]);

}

public function equal(paramVect:Vect):Boolean {

return ((paramVect.d[0] == d[0]) && (paramVect.d[1] == this.d[1]) && (paramVect.d[2] == this.d[2]));

}

public function mul(paramFloat:Number):void {

d[0] *= paramFloat;

d[1] *= paramFloat;

d[2] *= paramFloat;

}

public function div(paramFloat:Number):void {

d[0] /= paramFloat;

d[1] /= paramFloat;

d[2] /= paramFloat;

}

public function add(paramVect:Vect):void {

d[0] += paramVect.d[0];

d[1] += paramVect.d[1];

d[2] += paramVect.d[2];

}

public function sub(paramVect:Vect):void {

d[0] -= paramVect.d[0];

d[1] -= paramVect.d[1];

d[2] -= paramVect.d[2];

}

public function dot(paramVect:Vect):Number {

return (d[0] * paramVect.d[0] + d[1] * paramVect.d[1] + d[2] * paramVect.d[2]);

}

public function cross(paramVect:Vect):Vect {

return new Vect(d[1] * paramVect.d[2] - (d[2] * paramVect.d[1]), d[2] * paramVect.d[0] - (d[0] * paramVect.d[2]), d[0] * paramVect.d[1] - (d[1] * paramVect.d[0]));

}

public function normalize():void {

mul(1.0 / magnitude());

}

public function project():void {

d[2] += 256.0;

d[0] *= 1024.0 / d[2];

d[1] *= 1024.0 / d[2];

}

public function copy():Vect {

return new Vect(d[0], d[1], d[2]);

}

Matrix.as

package {
	
	/**
	 * @author Gordon Williams (http://www.rabidhamster.org/index.php)
	 * 
	 * Java to Actionscript port by:
	 * @author Devon O. Wolfgang (http://blog.onebyonedesign.com)
	 */
	
	public class Matrix {
		
		public var m:Vector.<Vector.<Number>> = new Vector.<Vector.<Number>>();
		
		public function Matrix() {
			m.length = 4;
			m.fixed = true;
			var i:int = 4;
			while (i--) {
				var v:Vector.<Number> = new Vector.<Number>();
				v.length = 4;
				v.fixed = true;
				m[i] = v;
			}
			setZero();
		}

		public function setZero():void {
			for (var i:int = 0; i < 4; ++i) {
				for (var j:int = 0; j < 4; ++j ) { 
					this.m[i][j] = 0.0;
				}
			}
		}

		public function setIdentity():void {
			setZero();
			m[0][0] = 1.0;
			m[1][1] = 1.0;
			m[2][2] = 1.0;
			m[3][3] = 1.0;
		}

		public function setTranslate(...args:Array):void {
			if (args.length == 1) {
				setTranslate(args[0].d[0], args[0].d[1], args[0].d[2]);
			} else if (args.length == 3) {
				setIdentity();
				m[3][0] = args[0];
				m[3][1] = args[1];
				m[3][2] = args[2];
			}
		}

		public function setRotateX(paramFloat:Number):void  {
			setIdentity();
			m[2][2] = (m[1][1] = Math.cos(paramFloat));
			m[2][1] = (-(m[1][2] = Math.sin(paramFloat)));
		}

		public function setRotateY(paramFloat:Number):void {
			setIdentity();
			m[2][2] = (m[0][0] = Math.cos(paramFloat));
			m[0][2] = (-(m[2][0] = Math.sin(paramFloat)));
		}

		public function setRotateZ(paramFloat:Number):void {
			setIdentity();
			m[0][0] = (m[1][1] = Math.cos(paramFloat));
			m[1][0] = (-(m[0][1] = Math.sin(paramFloat)));
		}

		public function setScale(...args:Array):void {
			if (args.length == 1) {
				setScale(args[0].d[0], args[0].paramVect.d[1], args[0].paramVect.d[2]);
			} else if (args.length == 3) {
				setIdentity();
				m[0][0] = args[0];
				m[1][1] = args[1];
				m[2][2] = args[2];
			}
		}

		public function mul(paramMatrix:Matrix):Matrix {
			var localMatrix:Matrix = new Matrix();
			for (var i:int = 0; i < 4; ++i)
				for (var j:int = 0; j < 4; ++j)
					for (var k:int = 0; k < 4; ++k)
						localMatrix.m[i][j] += this.m[i][k] * paramMatrix.m[k][j];

			return localMatrix;
		}

		public function apply(paramVect:Vect):Vect {
			var localVect:Vect = new Vect(0.0, 0.0, 0.0);
			for (var i:int = 0; i < 4; ++i)
				for (var j:int = 0; j < 4; ++j)
					localVect.d[i] += paramVect.d[j] * m[j][i];

			return localVect;
		}

		public function copy():Matrix {
			var localMatrix:Matrix = new Matrix();
			for (var i:int = 0; i < 4; ++i)
				for (var j:int = 0; j < 4; ++j)
					localMatrix.m[i][j] = this.m[i][j];


			return localMatrix;
		}	
	}
}

100

101

102

103

104

105

106

107

108

109

110

111

112

package {

/**

* @author Gordon Williams (http://www.rabidhamster.org/index.php)

* Java to Actionscript port by:

* @author Devon O. Wolfgang (http://blog.onebyonedesign.com)

public class Matrix {

public var m:Vector.<Vector.<Number>> = new Vector.<Vector.<Number>>();

public function Matrix() {

m.length = 4;

m.fixed = true;

var i:int = 4;

while (i--) {

var v:Vector.<Number> = new Vector.<Number>();

v.length = 4;

v.fixed = true;

m[i] = v;

}

setZero();

}

public function setZero():void {

for (var i:int = 0; i < 4; ++i) {

for (var j:int = 0; j < 4; ++j ) {

this.m[i][j] = 0.0;

}

public function setIdentity():void {

setZero();

m[0][0] = 1.0;

m[1][1] = 1.0;

m[2][2] = 1.0;

m[3][3] = 1.0;

}

public function setTranslate(...args:Array):void {

if (args.length == 1) {

setTranslate(args[0].d[0], args[0].d[1], args[0].d[2]);

} else if (args.length == 3) {

setIdentity();

m[3][0] = args[0];

m[3][1] = args[1];

m[3][2] = args[2];

}

public function setRotateX(paramFloat:Number):void {

setIdentity();

m[2][2] = (m[1][1] = Math.cos(paramFloat));

m[2][1] = (-(m[1][2] = Math.sin(paramFloat)));

}

public function setRotateY(paramFloat:Number):void {

setIdentity();

m[2][2] = (m[0][0] = Math.cos(paramFloat));

m[0][2] = (-(m[2][0] = Math.sin(paramFloat)));

}

public function setRotateZ(paramFloat:Number):void {

setIdentity();

m[0][0] = (m[1][1] = Math.cos(paramFloat));

m[1][0] = (-(m[0][1] = Math.sin(paramFloat)));

}

public function setScale(...args:Array):void {

if (args.length == 1) {

setScale(args[0].d[0], args[0].paramVect.d[1], args[0].paramVect.d[2]);

} else if (args.length == 3) {

setIdentity();

m[0][0] = args[0];

m[1][1] = args[1];

m[2][2] = args[2];

}

public function mul(paramMatrix:Matrix):Matrix {

var localMatrix:Matrix = new Matrix();

for (var i:int = 0; i < 4; ++i)

for (var j:int = 0; j < 4; ++j)

for (var k:int = 0; k < 4; ++k)

localMatrix.m[i][j] += this.m[i][k] * paramMatrix.m[k][j];

return localMatrix;

}

public function apply(paramVect:Vect):Vect {

var localVect:Vect = new Vect(0.0, 0.0, 0.0);

for (var i:int = 0; i < 4; ++i)

for (var j:int = 0; j < 4; ++j)

localVect.d[i] += paramVect.d[j] * m[j][i];

return localVect;

}

public function copy():Matrix {

var localMatrix:Matrix = new Matrix();

for (var i:int = 0; i < 4; ++i)

for (var j:int = 0; j < 4; ++j)

localMatrix.m[i][j] = this.m[i][j];

return localMatrix;

}

And the main Metaball class :

package {
	
	/**
	 * @author Gordon Williams (http://www.rabidhamster.org/index.php)
	 * 
	 * Java to Actionscript port by:
	 * @author Devon O. Wolfgang (http://blog.onebyonedesign.com)
	 */

	import flash.display.Bitmap;
	import flash.display.BitmapData;
	import flash.display.Sprite;
	import flash.events.Event;
	import flash.utils.getTimer;


	public class MetaBall extends Sprite {
		
		private var MIDX:int;
		private var MIDY:int;
		private var MAXX:int;
		private var MAXY:int;
		
		private var _oldtime:Number;
		private var _newtime:Number;
		private var _timepass:Number;
		private var _time:Number;
		private var _pMatrix:Matrix;
		private var _pixels:Vector.<uint>;
		private var _grid:Vector.<Number> = new Vector.<Number>();
		private var _thresh:Number;
		private var _balls:Vector.<Vect> = new Vector.<Vect>();
		private var _ballFreq:Vector.<Vect> = new Vector.<Vect>();
		private var _ballOfs:Vector.<Vect> = new Vector.<Vect>();
		
		private var _meshData:Array;
		private var _squareData:Array;
		
		private var _canvas:BitmapData;
		private var _display:Bitmap;
		
		public function MetaBall(width:int, height:int, numBalls:int = 5) {
			
			_canvas = new BitmapData(width, height, false, 0x000000);
			_display = new Bitmap(_canvas);
			addChild(_display);
			
			_oldtime = 0;
			_newtime = 0;
			_timepass = 0.0;
			_time = 0.0;

			_grid.length = 4096;
			_grid.fixed = true;
			
			_thresh = 0.23;
			
			_balls.length = numBalls;
			_balls.fixed = true;
			_ballFreq.length = numBalls;
			_ballFreq.fixed = true;
			_ballOfs.length = numBalls;
			_ballOfs.fixed = true;
			
			MIDX = int(_canvas.width * .5);
			MIDY = int(_canvas.height * .5);
			MAXX = _canvas.width;
			MAXY = _canvas.height;

			_meshData = [ [], [ 0, 3 ], [ 1, 0 ], [ 1, 3 ], [ 3, 2 ], [ 0, 2 ],[ 3, 0, 1, 2 ],[ 1, 2 ], [ 2, 1 ], [ 0, 1, 2, 3 ], [ 2, 0 ], [ 2, 3 ], [ 3, 1 ], [ 0, 1], [ 3, 0 ], [] ];

			_squareData = [];
			
			init();
		}

		public function init():void {
			initBuffers();
			
			var len:int = _balls.length;
			for (var i:int = 0; i < len;  ++i) {
				_ballFreq[i] = new Vect(Math.random() + 0.5, Math.random() + 0.5, Math.random() + 0.5);
				_ballOfs[i] = new Vect(Math.random() * Math.PI, Math.random() * Math.PI, Math.random() * Math.PI);
			}
		}

		protected function initBuffers():void {
			_pixels = new Vector.<uint>();
			_pixels.length = _canvas.width * _canvas.height;
			_pixels.fixed = true;
		}

		private function ballVal(paramFloat1:Number, paramFloat2:Number, paramFloat3:Number):Number {
			var f:Number = paramFloat1 * paramFloat1 + paramFloat2 * paramFloat2 + paramFloat3 * paramFloat3;
			if (f > 1.0) return (1.0 / f); 
			return 1.0;
		}

		private function gridFill():void {
			var i:int = 0;
			var len:int = _balls.length;
			for (var j:int = 0; j < 16; ++j)
				for (var k:int = 0; k < 16; ++k)
					for (var l:int = 0; l < 16; ++l) {
						_grid[i] = 0.0;
						for (var i1:int = 0; i1 < len; ++i1)
							_grid[i] += ballVal(l + _balls[i1].d[0] - 8.0, k + _balls[i1].d[1] - 8.0, j + _balls[i1].d[2] - 8.0);
						++i;
					}
		}

		private function diff(paramFloat1:Number, paramFloat2:Number):Number {
			if (paramFloat2 != paramFloat1) {
				var f:Number = (_thresh - paramFloat1) / (paramFloat2 - paramFloat1);

				return f;
			}
			return 0.0;
		}

		private function getVectXY(paramInt:int, paramFloat1:Number, paramFloat2:Number, paramFloat3:Number):Vect {
			switch (paramInt) {
				case 0:
					return new Vect(paramFloat1 + diff(_squareData[0], _squareData[1]), paramFloat2, paramFloat3);
				case 1:
					return new Vect(paramFloat1 + 1.0, paramFloat2 + diff(_squareData[1], _squareData[3]), paramFloat3);
				case 2:
					return new Vect(paramFloat1 + diff(_squareData[2], _squareData[3]), paramFloat2 + 1.0, paramFloat3);
				case 3:
					return new Vect(paramFloat1, paramFloat2 + diff(_squareData[0], _squareData[2]), paramFloat3);
				default:
					return new Vect(0.0, 0.0, 0.0);
			}
		}

		private function getVectYZ(paramInt:int, paramFloat1:Number, paramFloat2:Number, paramFloat3:Number):Vect {
			switch (paramInt) {
				case 0:
					return new Vect(paramFloat1, paramFloat2 + diff(_squareData[0], _squareData[1]), paramFloat3);
				case 1:
					return new Vect(paramFloat1, paramFloat2 + 1.0, paramFloat3 + diff(_squareData[1], _squareData[3]));
				case 2:
					return new Vect(paramFloat1, paramFloat2 + diff(_squareData[2], _squareData[3]), paramFloat3 + 1.0);
				case 3:
					return new Vect(paramFloat1, paramFloat2, paramFloat3 + diff(_squareData[0], _squareData[2]));
				default:
					return new Vect(0.0, 0.0, 0.0);
			}
		}

		private function getVectZX(paramInt:int, paramFloat1:Number, paramFloat2:Number, paramFloat3:Number):Vect {
			switch (paramInt) {
				case 0:
					return new Vect(paramFloat1, paramFloat2, paramFloat3 + diff(_squareData[0], _squareData[1]));
				case 1:
					return new Vect(paramFloat1 + diff(_squareData[1], _squareData[3]), paramFloat2, paramFloat3 + 1.0);
				case 2:
					return new Vect(paramFloat1 + 1.0, paramFloat2, paramFloat3 + diff(_squareData[2], _squareData[3]));
				case 3:
					return new Vect(paramFloat1 + diff(_squareData[0], _squareData[2]), paramFloat2, paramFloat3);
				default:
					return new Vect(0.0, 0.0, 0.0);
			}
		}

		private function gridMesh():void {
			var i:int = 0;
			
			for (var j:int = 0; j < 15; ++j)
				for (var k:int = 0; k < 16; ++k)
					for (var l:int = 0; l < 16; ++l) {
						if ((l < 15) && (k < 15)) {
							var i1:int = 0;
							if ((_squareData[0] = _grid[i]) > _thresh) ++i1;
							if ((_squareData[1] = _grid[(i + 1)]) > _thresh) i1 += 2;
							if ((_squareData[2] = _grid[(i + 16)]) > _thresh) i1 += 4;
							if ((_squareData[3] = _grid[(i + 17)]) > _thresh) i1 += 8;
							var len:int = _meshData[i1].length;
							for (var i2:int = 0; i2 < len; i2 += 2)
								line(getVectXY(_meshData[i1][i2], l, k, j), getVectXY(_meshData[i1][(i2 + 1)], l, k, j));

							i1 = 0;
							if ((_squareData[0] = _grid[i]) > _thresh) ++i1;
							if ((_squareData[1] = _grid[(i + 16)]) > _thresh) i1 += 2;
							if ((_squareData[2] = _grid[(i + 256)]) > _thresh) i1 += 4;
							if ((_squareData[3] = _grid[(i + 272)]) > _thresh) i1 += 8;
							len = _meshData[i1].length;
							for (var i3:int = 0; i3 < len; i3 += 2)
								line(getVectYZ(_meshData[i1][i3], l, k, j), getVectYZ(_meshData[i1][(i3 + 1)], l, k, j));

							i1 = 0;
							if ((_squareData[0] = _grid[i]) > _thresh) ++i1;
							if ((_squareData[1] = _grid[(i + 256)]) > _thresh) i1 += 2;
							if ((_squareData[2] = _grid[(i + 1)]) > _thresh) i1 += 4;
							if ((_squareData[3] = _grid[(i + 257)]) > _thresh) i1 += 8;
							len = _meshData[i1].length;
							for (var i4:int = 0; i4 < len; i4 += 2)
								line(getVectZX(_meshData[i1][i4], l, k, j), getVectZX(_meshData[i1][(i4 + 1)], l, k, j));
						}
						++i;
					}
		}

		private function line(paramVect1:Vect, paramVect2:Vect):void {
			paramVect1 = _pMatrix.apply(paramVect1);
			paramVect2 = _pMatrix.apply(paramVect2);
			paramVect1.project();
			paramVect2.project();
			drawLineAA(paramVect1.d[0] + MIDX, paramVect1.d[1] + MIDY, paramVect2.d[0] + MIDX, paramVect2.d[1] + MIDY, 100);
		}

		public function paint():void {
			
			var i:int = _canvas.width * _canvas.height;
			var j:int = _canvas.width;
			
			
			for (var k:int = j; k < i - j; ++k) {
				// original line
				//this._pixels[k] = ((this._pixels[k] & 0xFF) * 7 + ((this._pixels[(k - 1)] & 0xFF) + (this._pixels[(k + 1)] & 0xFF) + (this._pixels[(k - j)] & 0xFF) + (this._pixels[(k + j)] & 0xFF)) * 2 >> 4);
				
				this._pixels[k] = ((_pixels[k] & 0xFF) * 3 + ((_pixels[(k - 1)] & 0xFF) + (_pixels[(k + 1)] & 0xFF) + (_pixels[(k - j)] & 0xFF) + (_pixels[(k + j)] & 0xFF)) * 2 >> 4);
				
			}

			_oldtime = _newtime;
			_newtime = getTimer();
			_timepass = _newtime - _oldtime;
			_timepass /= 1000.0;
			_time += _timepass;

			var localMatrix1:Matrix = new Matrix();

			var localMatrix2:Matrix = new Matrix();
			localMatrix2.setTranslate(-8.0, -8.0, -8.0);
			localMatrix1.setRotateX(_time);
			localMatrix2 = localMatrix2.mul(localMatrix1);
			localMatrix1.setRotateY(_time * 1.375);
			localMatrix2 = localMatrix2.mul(localMatrix1);
			localMatrix1.setScale(5.0, 5.0, 5.0);
			_pMatrix = localMatrix2.mul(localMatrix1);

			var l:int = _balls.length;
			while (l--)  {
				_balls[l] = new Vect((Math.sin(_ballFreq[l].d[0] * _time + _ballOfs[l].d[0]) * 3.5), (Math.sin(_ballFreq[l].d[1] * _time + _ballOfs[l].d[1]) * 3.5), (Math.sin(_ballFreq[l].d[2] * _time + _ballOfs[l].d[2]) * 3.5));
			}

			gridFill();

			gridMesh();
			
			_canvas.lock();
			var kk:int = 0;
			var ii:int = _canvas.height;
			while (ii--) {
				var jj:int = _canvas.width;
				while(jj--) {
					_canvas.setPixel(jj, ii, _pixels[kk]);
					kk++;
				}
			}
			_canvas.unlock();
		}

		public function start():void {
			_newtime = (_oldtime = getTimer());
			addEventListener(Event.ENTER_FRAME, update);
		}

		public function stop():void {
			removeEventListener(Event.ENTER_FRAME, update);
		}

		private function update(event:Event):void {
			paint();
		}

		private function drawLineAA(paramDouble1:Number, paramDouble2:Number, paramDouble3:Number, paramDouble4:Number,  paramInt:int):void {
			var i7:int;
			var i8:int;
			var i9:int;
			var i10:int;
			var i:int = int(65536.0 * paramDouble1);
			var j:int = int(65536.0 * paramDouble3);
			var k:int = int(65536.0 * paramDouble2);
			var l:int = int(65536.0 * paramDouble4);
			var i1:int = i;
			var i2:int = j;
			var i3:int = k;
			var i4:int = l;
			var i5:int = i2 - i1;
			var i6:int = i4 - i3;

			if (Math.abs(paramDouble3 - paramDouble1) > Math.abs(paramDouble4 - paramDouble2)) {
				if (i2 < i1) {
					i1 = j;
					i2 = i;
					i3 = l;
				}

				i7 = i3;
				i8 = (i5 >> 16 == 0) ? i6 : i6 / (i5 >> 16);

				for (i9 = i1 >> 16; i9 < i2 + 32767 >> 16; ++i9) {
					i10 = i7 >> 16;
					drawPixelAA(i9, i10, _canvas.width, i7, paramInt);
					i7 += i8;
				}
			} else {
				if (i4 < i3) {
					i1 = j;
					i3 = l;
					i4 = k;
				}

				i7 = i1;
				i8 = (i6 >> 16 == 0) ? i5 : i5 / (i6 >> 16);

				for (i9 = i3 >> 16; i9 < i4 + 32767 >> 16; ++i9) {
					i10 = i7 >> 16;
					drawPixelAA(i10, i9, 1, i7, paramInt);
					i7 += i8;
				}
			}
		}

		private function drawPixelAA(paramInt1:int, paramInt2:int, paramInt3:int, paramInt4:int, paramInt5:int):void {
			if ((paramInt2 >= 0) && (paramInt2 < _canvas.height - 1) && (paramInt1 >= 0) && (paramInt1 < _canvas.width - 1)) {
				var i:int = paramInt2 * _canvas.width + paramInt1;
				if ((i < 0) || (i >= _canvas.width * _canvas.height)) return;

				var l1:Number = this._pixels[i];
				var l2:Number = this._pixels[(i + paramInt3)];

				if (l1 < 0) l1 = 256 + l1;
				if (l2 < 0) l2 = 256 + l2;
				
				var l3:Number = paramInt4 & 0xFFFF;
				var l4:Number = 65536 - l3;

				var l5:Number = paramInt5 * l4 >> 16;
				var l6:Number = paramInt5 * l3 >> 16;

				l1 += l5;
				l2 += l6;

				this._pixels[i] = ((l1 < 255) ? l1 : 0x000000);
				if (paramInt3 != 0) {
					i += paramInt3;
					if ((i < 0) || (i >= _canvas.width * _canvas.height)) return;

					this._pixels[i] = ((l2 < 255) ? l2 : 0x000000);
				}
			}
		}
	}
}

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283

284

285

286

287

288

289

290

291

292

293

294

295

296

297

298

299

300

301

302

303

304

305

306

307

308

309

310

311

312

313

314

315

316

317

318

319

320

321

322

323

324

325

326

327

328

329

330

331

332

333

334

335

336

337

338

339

340

341

342

343

344

345

346

347

348

349

350

351

352

353

354

355

356

357

package {

/**

* @author Gordon Williams (http://www.rabidhamster.org/index.php)

* Java to Actionscript port by:

* @author Devon O. Wolfgang (http://blog.onebyonedesign.com)

import flash.display.Bitmap;

import flash.display.BitmapData;

import flash.display.Sprite;

import flash.events.Event;

import flash.utils.getTimer;

public class MetaBall extends Sprite {

private var MIDX:int;

private var MIDY:int;

private var MAXX:int;

private var MAXY:int;

private var _oldtime:Number;

private var _newtime:Number;

private var _timepass:Number;

private var _time:Number;

private var _pMatrix:Matrix;

private var _pixels:Vector.<uint>;

private var _grid:Vector.<Number> = new Vector.<Number>();

private var _thresh:Number;

private var _balls:Vector.<Vect> = new Vector.<Vect>();

private var _ballFreq:Vector.<Vect> = new Vector.<Vect>();

private var _ballOfs:Vector.<Vect> = new Vector.<Vect>();

private var _meshData:Array;

private var _squareData:Array;

private var _canvas:BitmapData;

private var _display:Bitmap;

public function MetaBall(width:int, height:int, numBalls:int = 5) {

_canvas = new BitmapData(width, height, false, 0x000000);

_display = new Bitmap(_canvas);

addChild(_display);

_oldtime = 0;

_newtime = 0;

_timepass = 0.0;

_time = 0.0;

_grid.length = 4096;

_grid.fixed = true;

_thresh = 0.23;

_balls.length = numBalls;

_balls.fixed = true;

_ballFreq.length = numBalls;

_ballFreq.fixed = true;

_ballOfs.length = numBalls;

_ballOfs.fixed = true;

MIDX = int(_canvas.width * .5);

MIDY = int(_canvas.height * .5);

MAXX = _canvas.width;

MAXY = _canvas.height;

_meshData = [ [], [ 0, 3 ], [ 1, 0 ], [ 1, 3 ], [ 3, 2 ], [ 0, 2 ],[ 3, 0, 1, 2 ],[ 1, 2 ], [ 2, 1 ], [ 0, 1, 2, 3 ], [ 2, 0 ], [ 2, 3 ], [ 3, 1 ], [ 0, 1], [ 3, 0 ], [] ];

_squareData = [];

init();

}

public function init():void {

initBuffers();

var len:int = _balls.length;

for (var i:int = 0; i < len; ++i) {

_ballFreq[i] = new Vect(Math.random() + 0.5, Math.random() + 0.5, Math.random() + 0.5);

_ballOfs[i] = new Vect(Math.random() * Math.PI, Math.random() * Math.PI, Math.random() * Math.PI);

}

protected function initBuffers():void {

_pixels = new Vector.<uint>();

_pixels.length = _canvas.width * _canvas.height;

_pixels.fixed = true;

}

private function ballVal(paramFloat1:Number, paramFloat2:Number, paramFloat3:Number):Number {

var f:Number = paramFloat1 * paramFloat1 + paramFloat2 * paramFloat2 + paramFloat3 * paramFloat3;

if (f > 1.0) return (1.0 / f);

return 1.0;

}

private function gridFill():void {

var i:int = 0;

var len:int = _balls.length;

for (var j:int = 0; j < 16; ++j)

for (var k:int = 0; k < 16; ++k)

for (var l:int = 0; l < 16; ++l) {

_grid[i] = 0.0;

for (var i1:int = 0; i1 < len; ++i1)

_grid[i] += ballVal(l + _balls[i1].d[0] - 8.0, k + _balls[i1].d[1] - 8.0, j + _balls[i1].d[2] - 8.0);

++i;

}

private function diff(paramFloat1:Number, paramFloat2:Number):Number {

if (paramFloat2 != paramFloat1) {

var f:Number = (_thresh - paramFloat1) / (paramFloat2 - paramFloat1);

return f;

}

return 0.0;

}

private function getVectXY(paramInt:int, paramFloat1:Number, paramFloat2:Number, paramFloat3:Number):Vect {

switch (paramInt) {

case 0:

return new Vect(paramFloat1 + diff(_squareData[0], _squareData[1]), paramFloat2, paramFloat3);

case 1:

return new Vect(paramFloat1 + 1.0, paramFloat2 + diff(_squareData[1], _squareData[3]), paramFloat3);

case 2:

return new Vect(paramFloat1 + diff(_squareData[2], _squareData[3]), paramFloat2 + 1.0, paramFloat3);

case 3:

return new Vect(paramFloat1, paramFloat2 + diff(_squareData[0], _squareData[2]), paramFloat3);

default:

return new Vect(0.0, 0.0, 0.0);

}

private function getVectYZ(paramInt:int, paramFloat1:Number, paramFloat2:Number, paramFloat3:Number):Vect {

switch (paramInt) {

case 0:

return new Vect(paramFloat1, paramFloat2 + diff(_squareData[0], _squareData[1]), paramFloat3);

case 1:

return new Vect(paramFloat1, paramFloat2 + 1.0, paramFloat3 + diff(_squareData[1], _squareData[3]));

case 2:

return new Vect(paramFloat1, paramFloat2 + diff(_squareData[2], _squareData[3]), paramFloat3 + 1.0);

case 3:

return new Vect(paramFloat1, paramFloat2, paramFloat3 + diff(_squareData[0], _squareData[2]));

default:

return new Vect(0.0, 0.0, 0.0);

}

private function getVectZX(paramInt:int, paramFloat1:Number, paramFloat2:Number, paramFloat3:Number):Vect {

switch (paramInt) {

case 0:

return new Vect(paramFloat1, paramFloat2, paramFloat3 + diff(_squareData[0], _squareData[1]));

case 1:

return new Vect(paramFloat1 + diff(_squareData[1], _squareData[3]), paramFloat2, paramFloat3 + 1.0);

case 2:

return new Vect(paramFloat1 + 1.0, paramFloat2, paramFloat3 + diff(_squareData[2], _squareData[3]));

case 3:

return new Vect(paramFloat1 + diff(_squareData[0], _squareData[2]), paramFloat2, paramFloat3);

default:

return new Vect(0.0, 0.0, 0.0);

}

private function gridMesh():void {

var i:int = 0;

for (var j:int = 0; j < 15; ++j)

for (var k:int = 0; k < 16; ++k)

for (var l:int = 0; l < 16; ++l) {

if ((l < 15) && (k < 15)) {

var i1:int = 0;

if ((_squareData[0] = _grid[i]) > _thresh) ++i1;

if ((_squareData[1] = _grid[(i + 1)]) > _thresh) i1 += 2;

if ((_squareData[2] = _grid[(i + 16)]) > _thresh) i1 += 4;

if ((_squareData[3] = _grid[(i + 17)]) > _thresh) i1 += 8;

var len:int = _meshData[i1].length;

for (var i2:int = 0; i2 < len; i2 += 2)

line(getVectXY(_meshData[i1][i2], l, k, j), getVectXY(_meshData[i1][(i2 + 1)], l, k, j));

i1 = 0;

if ((_squareData[0] = _grid[i]) > _thresh) ++i1;

if ((_squareData[1] = _grid[(i + 16)]) > _thresh) i1 += 2;

if ((_squareData[2] = _grid[(i + 256)]) > _thresh) i1 += 4;

if ((_squareData[3] = _grid[(i + 272)]) > _thresh) i1 += 8;

len = _meshData[i1].length;

for (var i3:int = 0; i3 < len; i3 += 2)

line(getVectYZ(_meshData[i1][i3], l, k, j), getVectYZ(_meshData[i1][(i3 + 1)], l, k, j));

i1 = 0;

if ((_squareData[0] = _grid[i]) > _thresh) ++i1;

if ((_squareData[1] = _grid[(i + 256)]) > _thresh) i1 += 2;

if ((_squareData[2] = _grid[(i + 1)]) > _thresh) i1 += 4;

if ((_squareData[3] = _grid[(i + 257)]) > _thresh) i1 += 8;

len = _meshData[i1].length;

for (var i4:int = 0; i4 < len; i4 += 2)

line(getVectZX(_meshData[i1][i4], l, k, j), getVectZX(_meshData[i1][(i4 + 1)], l, k, j));

}

++i;

}

private function line(paramVect1:Vect, paramVect2:Vect):void {

paramVect1 = _pMatrix.apply(paramVect1);

paramVect2 = _pMatrix.apply(paramVect2);

paramVect1.project();

paramVect2.project();

drawLineAA(paramVect1.d[0] + MIDX, paramVect1.d[1] + MIDY, paramVect2.d[0] + MIDX, paramVect2.d[1] + MIDY, 100);

}

public function paint():void {

var i:int = _canvas.width * _canvas.height;

var j:int = _canvas.width;

for (var k:int = j; k < i - j; ++k) {

// original line

//this._pixels[k] = ((this._pixels[k] & 0xFF) * 7 + ((this._pixels[(k - 1)] & 0xFF) + (this._pixels[(k + 1)] & 0xFF) + (this._pixels[(k - j)] & 0xFF) + (this._pixels[(k + j)] & 0xFF)) * 2 >> 4);

this._pixels[k] = ((_pixels[k] & 0xFF) * 3 + ((_pixels[(k - 1)] & 0xFF) + (_pixels[(k + 1)] & 0xFF) + (_pixels[(k - j)] & 0xFF) + (_pixels[(k + j)] & 0xFF)) * 2 >> 4);

}

_oldtime = _newtime;

_newtime = getTimer();

_timepass = _newtime - _oldtime;

_timepass /= 1000.0;

_time += _timepass;

var localMatrix1:Matrix = new Matrix();

var localMatrix2:Matrix = new Matrix();

localMatrix2.setTranslate(-8.0, -8.0, -8.0);

localMatrix1.setRotateX(_time);

localMatrix2 = localMatrix2.mul(localMatrix1);

localMatrix1.setRotateY(_time * 1.375);

localMatrix2 = localMatrix2.mul(localMatrix1);

localMatrix1.setScale(5.0, 5.0, 5.0);

_pMatrix = localMatrix2.mul(localMatrix1);

var l:int = _balls.length;

while (l--) {

_balls[l] = new Vect((Math.sin(_ballFreq[l].d[0] * _time + _ballOfs[l].d[0]) * 3.5), (Math.sin(_ballFreq[l].d[1] * _time + _ballOfs[l].d[1]) * 3.5), (Math.sin(_ballFreq[l].d[2] * _time + _ballOfs[l].d[2]) * 3.5));

}

gridFill();

gridMesh();

_canvas.lock();

var kk:int = 0;

var ii:int = _canvas.height;

while (ii--) {

var jj:int = _canvas.width;

while(jj--) {

_canvas.setPixel(jj, ii, _pixels[kk]);

kk++;

}

_canvas.unlock();

}

public function start():void {

_newtime = (_oldtime = getTimer());

addEventListener(Event.ENTER_FRAME, update);

}

public function stop():void {

removeEventListener(Event.ENTER_FRAME, update);

}

private function update(event:Event):void {

paint();

}

private function drawLineAA(paramDouble1:Number, paramDouble2:Number, paramDouble3:Number, paramDouble4:Number, paramInt:int):void {

var i7:int;

var i8:int;

var i9:int;

var i10:int;

var i:int = int(65536.0 * paramDouble1);

var j:int = int(65536.0 * paramDouble3);

var k:int = int(65536.0 * paramDouble2);

var l:int = int(65536.0 * paramDouble4);

var i1:int = i;

var i2:int = j;

var i3:int = k;

var i4:int = l;

var i5:int = i2 - i1;

var i6:int = i4 - i3;

if (Math.abs(paramDouble3 - paramDouble1) > Math.abs(paramDouble4 - paramDouble2)) {

if (i2 < i1) {

i1 = j;

i2 = i;

i3 = l;

}

i7 = i3;

i8 = (i5 >> 16 == 0) ? i6 : i6 / (i5 >> 16);

for (i9 = i1 >> 16; i9 < i2 + 32767 >> 16; ++i9) {

i10 = i7 >> 16;

drawPixelAA(i9, i10, _canvas.width, i7, paramInt);

i7 += i8;

}

} else {

if (i4 < i3) {

i1 = j;

i3 = l;

i4 = k;

}

i7 = i1;

i8 = (i6 >> 16 == 0) ? i5 : i5 / (i6 >> 16);

for (i9 = i3 >> 16; i9 < i4 + 32767 >> 16; ++i9) {

i10 = i7 >> 16;

drawPixelAA(i10, i9, 1, i7, paramInt);

i7 += i8;

}

private function drawPixelAA(paramInt1:int, paramInt2:int, paramInt3:int, paramInt4:int, paramInt5:int):void {

if ((paramInt2 >= 0) && (paramInt2 < _canvas.height - 1) && (paramInt1 >= 0) && (paramInt1 < _canvas.width - 1)) {

var i:int = paramInt2 * _canvas.width + paramInt1;

if ((i < 0) || (i >= _canvas.width * _canvas.height)) return;

var l1:Number = this._pixels[i];

var l2:Number = this._pixels[(i + paramInt3)];

if (l1 < 0) l1 = 256 + l1;

if (l2 < 0) l2 = 256 + l2;

var l3:Number = paramInt4 & 0xFFFF;

var l4:Number = 65536 - l3;

var l5:Number = paramInt5 * l4 >> 16;

var l6:Number = paramInt5 * l3 >> 16;

l1 += l5;

l2 += l6;

this._pixels[i] = ((l1 < 255) ? l1 : 0x000000);

if (paramInt3 != 0) {

i += paramInt3;

if ((i < 0) || (i >= _canvas.width * _canvas.height)) return;

this._pixels[i] = ((l2 < 255) ? l2 : 0x000000);

}

Intantiation is easy – just create a new Metaball instance specifying its width, height and the number of balls (defaults to five) and add it to your display list.

Have no idea what you could do with the thing, but it sure is purty…

3 Comments:

If you like metaballs, you might like this guys stuff. He demo’d at Flash On rThe Beach last week.

http://prinzipiell.com/

It’s not russian bride spam honest.

Glen · October 02, 2009
I did see that guy speak at Elevator Pitch session. Great stuff. Thanks for the link Glen. And for not posting russion bride spam…

Devon O. · October 06, 2009
this is pretty cool. Nice work

dominic · November 01, 2009

None of This Runs Eternal

Feeling Lucky?

The Tendency Towards Web Dependency

3 Comments:

Leave a Comment! Cancel reply

Devon O. Wolfgang

Categories

Recent Comments

Archives