GZ/nwyj/WebContent/admin/scripts/dojo/dojox/gfx/decompose.js

if (!dojo._hasResource["dojox.gfx.decompose"]) { // _hasResource checks added
													// by build. Do not use
													// _hasResource directly in
													// your code.
	dojo._hasResource["dojox.gfx.decompose"] = true;
	dojo.provide("dojox.gfx.decompose");

	dojo.require("dojox.gfx.matrix");

	(function() {
		var m = dojox.gfx.matrix;

		var eq = function(/* Number */a, /* Number */b) {
			// summary: compare two FP numbers for equality
			return Math.abs(a - b) <= 1e-6 * (Math.abs(a) + Math.abs(b)); // Boolean
		};

		var calcFromValues = function(/* Number */r1, /* Number */m1, /* Number */
				r2, /* Number */m2) {
			// summary: uses two close FP ration and their original magnitudes
			// to approximate the result
			if (!isFinite(r1)) {
				return r2; // Number
			} else if (!isFinite(r2)) {
				return r1; // Number
			}
			m1 = Math.abs(m1), m2 = Math.abs(m2);
			return (m1 * r1 + m2 * r2) / (m1 + m2); // Number
		};

		var transpose = function(/* dojox.gfx.matrix.Matrix2D */matrix) {
			// matrix: dojox.gfx.matrix.Matrix2D: a 2D matrix-like object
			var M = new m.Matrix2D(matrix);
			return dojo.mixin(M, {
						dx : 0,
						dy : 0,
						xy : M.yx,
						yx : M.xy
					}); // dojox.gfx.matrix.Matrix2D
		};

		var scaleSign = function(/* dojox.gfx.matrix.Matrix2D */matrix) {
			return (matrix.xx * matrix.yy < 0 || matrix.xy * matrix.yx > 0)
					? -1
					: 1; // Number
		};

		var eigenvalueDecomposition = function(
/* dojox.gfx.matrix.Matrix2D */matrix) {
			// matrix: dojox.gfx.matrix.Matrix2D: a 2D matrix-like object
			var M = m.normalize(matrix), b = -M.xx - M.yy, c = M.xx * M.yy
					- M.xy * M.yx, d = Math.sqrt(b * b - 4 * c), l1 = -(b + (b < 0
					? -d
					: d))
					/ 2, l2 = c / l1, vx1 = M.xy / (l1 - M.xx), vy1 = 1, vx2 = M.xy
					/ (l2 - M.xx), vy2 = 1;
			if (eq(l1, l2)) {
				vx1 = 1, vy1 = 0, vx2 = 0, vy2 = 1;
			}
			if (!isFinite(vx1)) {
				vx1 = 1, vy1 = (l1 - M.xx) / M.xy;
				if (!isFinite(vy1)) {
					vx1 = (l1 - M.yy) / M.yx, vy1 = 1;
					if (!isFinite(vx1)) {
						vx1 = 1, vy1 = M.yx / (l1 - M.yy);
					}
				}
			}
			if (!isFinite(vx2)) {
				vx2 = 1, vy2 = (l2 - M.xx) / M.xy;
				if (!isFinite(vy2)) {
					vx2 = (l2 - M.yy) / M.yx, vy2 = 1;
					if (!isFinite(vx2)) {
						vx2 = 1, vy2 = M.yx / (l2 - M.yy);
					}
				}
			}
			var d1 = Math.sqrt(vx1 * vx1 + vy1 * vy1), d2 = Math.sqrt(vx2 * vx2
					+ vy2 * vy2);
			if (!isFinite(vx1 /= d1)) {
				vx1 = 0;
			}
			if (!isFinite(vy1 /= d1)) {
				vy1 = 0;
			}
			if (!isFinite(vx2 /= d2)) {
				vx2 = 0;
			}
			if (!isFinite(vy2 /= d2)) {
				vy2 = 0;
			}
			return { // Object
				value1 : l1,
				value2 : l2,
				vector1 : {
					x : vx1,
					y : vy1
				},
				vector2 : {
					x : vx2,
					y : vy2
				}
			};
		};

		var decomposeSR = function(/* dojox.gfx.matrix.Matrix2D */M, /* Object */
				result) {
			// summary: decomposes a matrix into [scale, rotate]; no checks are
			// done.
			var sign = scaleSign(M), a = result.angle1 = (Math
					.atan2(M.yx, M.yy) + Math.atan2(-sign * M.xy, sign * M.xx))
					/ 2, cos = Math.cos(a), sin = Math.sin(a);
			result.sx = calcFromValues(M.xx / cos, cos, -M.xy / sin, sin);
			result.sy = calcFromValues(M.yy / cos, cos, M.yx / sin, sin);
			return result; // Object
		};

		var decomposeRS = function(/* dojox.gfx.matrix.Matrix2D */M, /* Object */
				result) {
			// summary: decomposes a matrix into [rotate, scale]; no checks are
			// done
			var sign = scaleSign(M), a = result.angle2 = (Math.atan2(sign
							* M.yx, sign * M.xx) + Math.atan2(-M.xy, M.yy))
					/ 2, cos = Math.cos(a), sin = Math.sin(a);
			result.sx = calcFromValues(M.xx / cos, cos, M.yx / sin, sin);
			result.sy = calcFromValues(M.yy / cos, cos, -M.xy / sin, sin);
			return result; // Object
		};

		dojox.gfx.decompose = function(matrix) {
			// summary: decompose a 2D matrix into translation, scaling, and
			// rotation components
			// description: this function decompose a matrix into four logical
			// components:
			// translation, rotation, scaling, and one more rotation using SVD.
			// The components should be applied in following order:
			// | [translate, rotate(angle2), scale, rotate(angle1)]
			// matrix: dojox.gfx.matrix.Matrix2D: a 2D matrix-like object
			var M = m.normalize(matrix), result = {
				dx : M.dx,
				dy : M.dy,
				sx : 1,
				sy : 1,
				angle1 : 0,
				angle2 : 0
			};
			// detect case: [scale]
			if (eq(M.xy, 0) && eq(M.yx, 0)) {
				return dojo.mixin(result, {
							sx : M.xx,
							sy : M.yy
						}); // Object
			}
			// detect case: [scale, rotate]
			if (eq(M.xx * M.yx, -M.xy * M.yy)) {
				return decomposeSR(M, result); // Object
			}
			// detect case: [rotate, scale]
			if (eq(M.xx * M.xy, -M.yx * M.yy)) {
				return decomposeRS(M, result); // Object
			}
			// do SVD
			var MT = transpose(M), u = eigenvalueDecomposition([M, MT]), v = eigenvalueDecomposition([
					MT, M]), U = new m.Matrix2D({
						xx : u.vector1.x,
						xy : u.vector2.x,
						yx : u.vector1.y,
						yy : u.vector2.y
					}), VT = new m.Matrix2D({
						xx : v.vector1.x,
						xy : v.vector1.y,
						yx : v.vector2.x,
						yy : v.vector2.y
					}), S = new m.Matrix2D([m.invert(U), M, m.invert(VT)]);
			decomposeSR(VT, result);
			S.xx *= result.sx;
			S.yy *= result.sy;
			decomposeRS(U, result);
			S.xx *= result.sx;
			S.yy *= result.sy;
			return dojo.mixin(result, {
						sx : S.xx,
						sy : S.yy
					}); // Object
		};
	})();

}