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/*Copyright (c) 2004-2006, The Dojo FoundationAll Rights Reserved.Licensed under the Academic Free License version 2.1 or above OR themodified BSD license. For more information on Dojo licensing, see:http://dojotoolkit.org/community/licensing.shtml*/dojo.provide("dojo.math.curves");dojo.require("dojo.math");dojo.math.curves = {Line:function (start, end) {this.start = start;this.end = end;this.dimensions = start.length;for (var i = 0; i < start.length; i++) {start[i] = Number(start[i]);}for (var i = 0; i < end.length; i++) {end[i] = Number(end[i]);}this.getValue = function (n) {var retVal = new Array(this.dimensions);for (var i = 0; i < this.dimensions; i++) {retVal[i] = ((this.end[i] - this.start[i]) * n) + this.start[i];}return retVal;};return this;}, Bezier:function (pnts) {this.getValue = function (step) {if (step >= 1) {return this.p[this.p.length - 1];}if (step <= 0) {return this.p[0];}var retVal = new Array(this.p[0].length);for (var k = 0; j < this.p[0].length; k++) {retVal[k] = 0;}for (var j = 0; j < this.p[0].length; j++) {var C = 0;var D = 0;for (var i = 0; i < this.p.length; i++) {C += this.p[i][j] * this.p[this.p.length - 1][0] * dojo.math.bernstein(step, this.p.length, i);}for (var l = 0; l < this.p.length; l++) {D += this.p[this.p.length - 1][0] * dojo.math.bernstein(step, this.p.length, l);}retVal[j] = C / D;}return retVal;};this.p = pnts;return this;}, CatmullRom:function (pnts, c) {this.getValue = function (step) {var percent = step * (this.p.length - 1);var node = Math.floor(percent);var progress = percent - node;var i0 = node - 1;if (i0 < 0) {i0 = 0;}var i = node;var i1 = node + 1;if (i1 >= this.p.length) {i1 = this.p.length - 1;}var i2 = node + 2;if (i2 >= this.p.length) {i2 = this.p.length - 1;}var u = progress;var u2 = progress * progress;var u3 = progress * progress * progress;var retVal = new Array(this.p[0].length);for (var k = 0; k < this.p[0].length; k++) {var x1 = (-this.c * this.p[i0][k]) + ((2 - this.c) * this.p[i][k]) + ((this.c - 2) * this.p[i1][k]) + (this.c * this.p[i2][k]);var x2 = (2 * this.c * this.p[i0][k]) + ((this.c - 3) * this.p[i][k]) + ((3 - 2 * this.c) * this.p[i1][k]) + (-this.c * this.p[i2][k]);var x3 = (-this.c * this.p[i0][k]) + (this.c * this.p[i1][k]);var x4 = this.p[i][k];retVal[k] = x1 * u3 + x2 * u2 + x3 * u + x4;}return retVal;};if (!c) {this.c = 0.7;} else {this.c = c;}this.p = pnts;return this;}, Arc:function (start, end, ccw) {var center = dojo.math.points.midpoint(start, end);var sides = dojo.math.points.translate(dojo.math.points.invert(center), start);var rad = Math.sqrt(Math.pow(sides[0], 2) + Math.pow(sides[1], 2));var theta = dojo.math.radToDeg(Math.atan(sides[1] / sides[0]));if (sides[0] < 0) {theta -= 90;} else {theta += 90;}dojo.math.curves.CenteredArc.call(this, center, rad, theta, theta + (ccw ? -180 : 180));}, CenteredArc:function (center, radius, start, end) {this.center = center;this.radius = radius;this.start = start || 0;this.end = end;this.getValue = function (n) {var retVal = new Array(2);var theta = dojo.math.degToRad(this.start + ((this.end - this.start) * n));retVal[0] = this.center[0] + this.radius * Math.sin(theta);retVal[1] = this.center[1] - this.radius * Math.cos(theta);return retVal;};return this;}, Circle:function (center, radius) {dojo.math.curves.CenteredArc.call(this, center, radius, 0, 360);return this;}, Path:function () {var curves = [];var weights = [];var ranges = [];var totalWeight = 0;this.add = function (curve, weight) {if (weight < 0) {dojo.raise("dojo.math.curves.Path.add: weight cannot be less than 0");}curves.push(curve);weights.push(weight);totalWeight += weight;computeRanges();};this.remove = function (curve) {for (var i = 0; i < curves.length; i++) {if (curves[i] == curve) {curves.splice(i, 1);totalWeight -= weights.splice(i, 1)[0];break;}}computeRanges();};this.removeAll = function () {curves = [];weights = [];totalWeight = 0;};this.getValue = function (n) {var found = false, value = 0;for (var i = 0; i < ranges.length; i++) {var r = ranges[i];if (n >= r[0] && n < r[1]) {var subN = (n - r[0]) / r[2];value = curves[i].getValue(subN);found = true;break;}}if (!found) {value = curves[curves.length - 1].getValue(1);}for (var j = 0; j < i; j++) {value = dojo.math.points.translate(value, curves[j].getValue(1));}return value;};function computeRanges() {var start = 0;for (var i = 0; i < weights.length; i++) {var end = start + weights[i] / totalWeight;var len = end - start;ranges[i] = [start, end, len];start = end;}}return this;}};