/src/away3d/filters/tasks/Filter3DBlurTask.as

  1package away3d.filters.tasks
  2{
  3	import away3d.cameras.Camera3D;
  4	import away3d.core.managers.Stage3DProxy;
  5
  6	import flash.display3D.Context3DProgramType;
  7
  8	import flash.display3D.textures.Texture;
  9
 10	public class Filter3DBlurTask extends Filter3DTaskBase
 11	{
 12		private static const MAX_BLUR : int = 6;
 13		private var _blurX : uint;
 14		private var _blurY : uint;
 15		private var _data : Vector.<Number>;
 16		private var _stepX : Number = 1;
 17		private var _stepY : Number = 1;
 18		private var _numSamples : uint;
 19
 20		public function Filter3DBlurTask(blurX : uint = 3, blurY : uint = 3)
 21		{
 22			super();
 23			_blurX = blurX;
 24			_blurY = blurY;
 25			_data = Vector.<Number>([0, 0, 0, 1, 0, 0, 0, 0]);
 26		}
 27
 28		public function get blurX() : uint
 29		{
 30			return _blurX;
 31		}
 32
 33		public function set blurX(value : uint) : void
 34		{
 35			_blurX = value;
 36
 37			if (_blurX > MAX_BLUR) _stepX = _blurX/MAX_BLUR;
 38			else _stepX = 1;
 39
 40			invalidateProgram3D();
 41			updateBlurData();
 42		}
 43
 44		public function get blurY() : uint
 45		{
 46			return _blurY;
 47		}
 48
 49		public function set blurY(value : uint) : void
 50		{
 51			_blurY = value;
 52
 53			invalidateProgram3D();
 54			updateBlurData();
 55		}
 56
 57		override protected function getFragmentCode() : String
 58		{
 59			var code : String;
 60
 61			_numSamples = 0;
 62
 63			code = 		"mov ft0, v0	\n" +
 64						"sub ft0.y, v0.y, fc0.y\n";
 65
 66			for (var y : Number = 0; y <= _blurY; y += _stepY) {
 67				if (y > 0) code += "sub ft0.x, v0.x, fc0.x\n";
 68				for (var x : Number = 0; x <= _blurX; x += _stepX) {
 69					++_numSamples;
 70					if (x == 0 && y == 0)
 71						code += "tex ft1, ft0, fs0 <2d,nearest,clamp>\n";
 72					else
 73						code += "tex ft2, ft0, fs0 <2d,nearest,clamp>\n" +
 74								"add ft1, ft1, ft2 \n";
 75
 76					if (x < _blurX)
 77						code += "add ft0.x, ft0.x, fc1.x	\n";
 78				}
 79				if (y < _blurY) code += "add ft0.y, ft0.y, fc1.y	\n";
 80			}
 81
 82			code += "mul oc, ft1, fc0.z";
 83
 84			_data[2] = 1/_numSamples;
 85
 86			return code;
 87		}
 88
 89		override public function activate(stage3DProxy : Stage3DProxy, camera3D : Camera3D, depthTexture : Texture) : void
 90		{
 91			stage3DProxy.context3D.setProgramConstantsFromVector(Context3DProgramType.FRAGMENT, 0, _data, 2);
 92		}
 93
 94		override protected function updateTextures(stage : Stage3DProxy) : void
 95		{
 96			super.updateTextures(stage);
 97
 98			updateBlurData();
 99		}
100
101		private function updateBlurData() : void
102		{
103			// todo: must be normalized using view size ratio
104			var invW : Number = 1/_textureWidth;
105			var invH : Number = 1/_textureHeight;
106
107			if (_blurX > MAX_BLUR) _stepX = _blurX/MAX_BLUR;
108			else _stepX = 1;
109
110			if (_blurY > MAX_BLUR) _stepY = _blurY/MAX_BLUR;
111			else _stepY = 1;
112
113			_data[0] = _blurX*.5*invW;
114			_data[1] = _blurY*.5*invH;
115			_data[4] = _stepX*invW;
116			_data[5] = _stepY*invH;
117		}
118	}
119}