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// https://d3js.org/d3-path/ Version 1.0.5. Copyright 2017 Mike Bostock.
(function (global, factory) {
typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
typeof define === 'function' && define.amd ? define(['exports'], factory) :
(factory((global.d3 = global.d3 || {})));
}(this, (function (exports) { 'use strict';
var pi = Math.PI;
var tau = 2 * pi;
var epsilon = 1e-6;
var tauEpsilon = tau - epsilon;
function Path() {
this._x0 = this._y0 = // start of current subpath
this._x1 = this._y1 = null; // end of current subpath
this._ = "";
}
function path() {
return new Path;
}
Path.prototype = path.prototype = {
constructor: Path,
moveTo: function(x, y) {
this._ += "M" + (this._x0 = this._x1 = +x) + "," + (this._y0 = this._y1 = +y);
},
closePath: function() {
if (this._x1 !== null) {
this._x1 = this._x0, this._y1 = this._y0;
this._ += "Z";
}
},
lineTo: function(x, y) {
this._ += "L" + (this._x1 = +x) + "," + (this._y1 = +y);
},
quadraticCurveTo: function(x1, y1, x, y) {
this._ += "Q" + (+x1) + "," + (+y1) + "," + (this._x1 = +x) + "," + (this._y1 = +y);
},
bezierCurveTo: function(x1, y1, x2, y2, x, y) {
this._ += "C" + (+x1) + "," + (+y1) + "," + (+x2) + "," + (+y2) + "," + (this._x1 = +x) + "," + (this._y1 = +y);
},
arcTo: function(x1, y1, x2, y2, r) {
x1 = +x1, y1 = +y1, x2 = +x2, y2 = +y2, r = +r;
var x0 = this._x1,
y0 = this._y1,
x21 = x2 - x1,
y21 = y2 - y1,
x01 = x0 - x1,
y01 = y0 - y1,
l01_2 = x01 * x01 + y01 * y01;
// Is the radius negative? Error.
if (r < 0) throw new Error("negative radius: " + r);
// Is this path empty? Move to (x1,y1).
if (this._x1 === null) {
this._ += "M" + (this._x1 = x1) + "," + (this._y1 = y1);
}
// Or, is (x1,y1) coincident with (x0,y0)? Do nothing.
else if (!(l01_2 > epsilon)) {}
// Or, are (x0,y0), (x1,y1) and (x2,y2) collinear?
// Equivalently, is (x1,y1) coincident with (x2,y2)?
// Or, is the radius zero? Line to (x1,y1).
else if (!(Math.abs(y01 * x21 - y21 * x01) > epsilon) || !r) {
this._ += "L" + (this._x1 = x1) + "," + (this._y1 = y1);
}
// Otherwise, draw an arc!
else {
var x20 = x2 - x0,
y20 = y2 - y0,
l21_2 = x21 * x21 + y21 * y21,
l20_2 = x20 * x20 + y20 * y20,
l21 = Math.sqrt(l21_2),
l01 = Math.sqrt(l01_2),
l = r * Math.tan((pi - Math.acos((l21_2 + l01_2 - l20_2) / (2 * l21 * l01))) / 2),
t01 = l / l01,
t21 = l / l21;
// If the start tangent is not coincident with (x0,y0), line to.
if (Math.abs(t01 - 1) > epsilon) {
this._ += "L" + (x1 + t01 * x01) + "," + (y1 + t01 * y01);
}
this._ += "A" + r + "," + r + ",0,0," + (+(y01 * x20 > x01 * y20)) + "," + (this._x1 = x1 + t21 * x21) + "," + (this._y1 = y1 + t21 * y21);
}
},
arc: function(x, y, r, a0, a1, ccw) {
x = +x, y = +y, r = +r;
var dx = r * Math.cos(a0),
dy = r * Math.sin(a0),
x0 = x + dx,
y0 = y + dy,
cw = 1 ^ ccw,
da = ccw ? a0 - a1 : a1 - a0;
// Is the radius negative? Error.
if (r < 0) throw new Error("negative radius: " + r);
// Is this path empty? Move to (x0,y0).
if (this._x1 === null) {
this._ += "M" + x0 + "," + y0;
}
// Or, is (x0,y0) not coincident with the previous point? Line to (x0,y0).
else if (Math.abs(this._x1 - x0) > epsilon || Math.abs(this._y1 - y0) > epsilon) {
this._ += "L" + x0 + "," + y0;
}
// Is this arc empty? Were done.
if (!r) return;
// Does the angle go the wrong way? Flip the direction.
if (da < 0) da = da % tau + tau;
// Is this a complete circle? Draw two arcs to complete the circle.
if (da > tauEpsilon) {
this._ += "A" + r + "," + r + ",0,1," + cw + "," + (x - dx) + "," + (y - dy) + "A" + r + "," + r + ",0,1," + cw + "," + (this._x1 = x0) + "," + (this._y1 = y0);
}
// Is this arc non-empty? Draw an arc!
else if (da > epsilon) {
this._ += "A" + r + "," + r + ",0," + (+(da >= pi)) + "," + cw + "," + (this._x1 = x + r * Math.cos(a1)) + "," + (this._y1 = y + r * Math.sin(a1));
}
},
rect: function(x, y, w, h) {
this._ += "M" + (this._x0 = this._x1 = +x) + "," + (this._y0 = this._y1 = +y) + "h" + (+w) + "v" + (+h) + "h" + (-w) + "Z";
},
toString: function() {
return this._;
}
};
exports.path = path;
Object.defineProperty(exports, '__esModule', { value: true });
})));