// https://d3js.org/d3-geo/ v3.1.0 Copyright 2010-2022 Mike Bostock, 2008-2012 Charles Karney (function (global, factory) { typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports, require('d3-array')) : typeof define === 'function' && define.amd ? define(['exports', 'd3-array'], factory) : (global = typeof globalThis !== 'undefined' ? globalThis : global || self, factory(global.d3 = global.d3 || {}, global.d3)); })(this, (function (exports, d3Array) { 'use strict'; var epsilon = 1e-6; var epsilon2 = 1e-12; var pi = Math.PI; var halfPi = pi / 2; var quarterPi = pi / 4; var tau = pi * 2; var degrees = 180 / pi; var radians = pi / 180; var abs = Math.abs; var atan = Math.atan; var atan2 = Math.atan2; var cos = Math.cos; var ceil = Math.ceil; var exp = Math.exp; var hypot = Math.hypot; var log = Math.log; var pow = Math.pow; var sin = Math.sin; var sign = Math.sign || function(x) { return x > 0 ? 1 : x < 0 ? -1 : 0; }; var sqrt = Math.sqrt; var tan = Math.tan; function acos(x) { return x > 1 ? 0 : x < -1 ? pi : Math.acos(x); } function asin(x) { return x > 1 ? halfPi : x < -1 ? -halfPi : Math.asin(x); } function haversin(x) { return (x = sin(x / 2)) * x; } function noop() {} function streamGeometry(geometry, stream) { if (geometry && streamGeometryType.hasOwnProperty(geometry.type)) { streamGeometryType[geometry.type](geometry, stream); } } var streamObjectType = { Feature: function(object, stream) { streamGeometry(object.geometry, stream); }, FeatureCollection: function(object, stream) { var features = object.features, i = -1, n = features.length; while (++i < n) streamGeometry(features[i].geometry, stream); } }; var streamGeometryType = { Sphere: function(object, stream) { stream.sphere(); }, Point: function(object, stream) { object = object.coordinates; stream.point(object[0], object[1], object[2]); }, MultiPoint: function(object, stream) { var coordinates = object.coordinates, i = -1, n = coordinates.length; while (++i < n) object = coordinates[i], stream.point(object[0], object[1], object[2]); }, LineString: function(object, stream) { streamLine(object.coordinates, stream, 0); }, MultiLineString: function(object, stream) { var coordinates = object.coordinates, i = -1, n = coordinates.length; while (++i < n) streamLine(coordinates[i], stream, 0); }, Polygon: function(object, stream) { streamPolygon(object.coordinates, stream); }, MultiPolygon: function(object, stream) { var coordinates = object.coordinates, i = -1, n = coordinates.length; while (++i < n) streamPolygon(coordinates[i], stream); }, GeometryCollection: function(object, stream) { var geometries = object.geometries, i = -1, n = geometries.length; while (++i < n) streamGeometry(geometries[i], stream); } }; function streamLine(coordinates, stream, closed) { var i = -1, n = coordinates.length - closed, coordinate; stream.lineStart(); while (++i < n) coordinate = coordinates[i], stream.point(coordinate[0], coordinate[1], coordinate[2]); stream.lineEnd(); } function streamPolygon(coordinates, stream) { var i = -1, n = coordinates.length; stream.polygonStart(); while (++i < n) streamLine(coordinates[i], stream, 1); stream.polygonEnd(); } function geoStream(object, stream) { if (object && streamObjectType.hasOwnProperty(object.type)) { streamObjectType[object.type](object, stream); } else { streamGeometry(object, stream); } } var areaRingSum$1 = new d3Array.Adder(); // hello? var areaSum$1 = new d3Array.Adder(), lambda00$2, phi00$2, lambda0$2, cosPhi0$1, sinPhi0$1; var areaStream$1 = { point: noop, lineStart: noop, lineEnd: noop, polygonStart: function() { areaRingSum$1 = new d3Array.Adder(); areaStream$1.lineStart = areaRingStart$1; areaStream$1.lineEnd = areaRingEnd$1; }, polygonEnd: function() { var areaRing = +areaRingSum$1; areaSum$1.add(areaRing < 0 ? tau + areaRing : areaRing); this.lineStart = this.lineEnd = this.point = noop; }, sphere: function() { areaSum$1.add(tau); } }; function areaRingStart$1() { areaStream$1.point = areaPointFirst$1; } function areaRingEnd$1() { areaPoint$1(lambda00$2, phi00$2); } function areaPointFirst$1(lambda, phi) { areaStream$1.point = areaPoint$1; lambda00$2 = lambda, phi00$2 = phi; lambda *= radians, phi *= radians; lambda0$2 = lambda, cosPhi0$1 = cos(phi = phi / 2 + quarterPi), sinPhi0$1 = sin(phi); } function areaPoint$1(lambda, phi) { lambda *= radians, phi *= radians; phi = phi / 2 + quarterPi; // half the angular distance from south pole // Spherical excess E for a spherical triangle with vertices: south pole, // previous point, current point. Uses a formula derived from Cagnoli’s // theorem. See Todhunter, Spherical Trig. (1871), Sec. 103, Eq. (2). var dLambda = lambda - lambda0$2, sdLambda = dLambda >= 0 ? 1 : -1, adLambda = sdLambda * dLambda, cosPhi = cos(phi), sinPhi = sin(phi), k = sinPhi0$1 * sinPhi, u = cosPhi0$1 * cosPhi + k * cos(adLambda), v = k * sdLambda * sin(adLambda); areaRingSum$1.add(atan2(v, u)); // Advance the previous points. lambda0$2 = lambda, cosPhi0$1 = cosPhi, sinPhi0$1 = sinPhi; } function area(object) { areaSum$1 = new d3Array.Adder(); geoStream(object, areaStream$1); return areaSum$1 * 2; } function spherical(cartesian) { return [atan2(cartesian[1], cartesian[0]), asin(cartesian[2])]; } function cartesian(spherical) { var lambda = spherical[0], phi = spherical[1], cosPhi = cos(phi); return [cosPhi * cos(lambda), cosPhi * sin(lambda), sin(phi)]; } function cartesianDot(a, b) { return a[0] * b[0] + a[1] * b[1] + a[2] * b[2]; } function cartesianCross(a, b) { return [a[1] * b[2] - a[2] * b[1], a[2] * b[0] - a[0] * b[2], a[0] * b[1] - a[1] * b[0]]; } // TODO return a function cartesianAddInPlace(a, b) { a[0] += b[0], a[1] += b[1], a[2] += b[2]; } function cartesianScale(vector, k) { return [vector[0] * k, vector[1] * k, vector[2] * k]; } // TODO return d function cartesianNormalizeInPlace(d) { var l = sqrt(d[0] * d[0] + d[1] * d[1] + d[2] * d[2]); d[0] /= l, d[1] /= l, d[2] /= l; } var lambda0$1, phi0, lambda1, phi1, // bounds lambda2, // previous lambda-coordinate lambda00$1, phi00$1, // first point p0, // previous 3D point deltaSum, ranges, range; var boundsStream$1 = { point: boundsPoint$1, lineStart: boundsLineStart, lineEnd: boundsLineEnd, polygonStart: function() { boundsStream$1.point = boundsRingPoint; boundsStream$1.lineStart = boundsRingStart; boundsStream$1.lineEnd = boundsRingEnd; deltaSum = new d3Array.Adder(); areaStream$1.polygonStart(); }, polygonEnd: function() { areaStream$1.polygonEnd(); boundsStream$1.point = boundsPoint$1; boundsStream$1.lineStart = boundsLineStart; boundsStream$1.lineEnd = boundsLineEnd; if (areaRingSum$1 < 0) lambda0$1 = -(lambda1 = 180), phi0 = -(phi1 = 90); else if (deltaSum > epsilon) phi1 = 90; else if (deltaSum < -epsilon) phi0 = -90; range[0] = lambda0$1, range[1] = lambda1; }, sphere: function() { lambda0$1 = -(lambda1 = 180), phi0 = -(phi1 = 90); } }; function boundsPoint$1(lambda, phi) { ranges.push(range = [lambda0$1 = lambda, lambda1 = lambda]); if (phi < phi0) phi0 = phi; if (phi > phi1) phi1 = phi; } function linePoint(lambda, phi) { var p = cartesian([lambda * radians, phi * radians]); if (p0) { var normal = cartesianCross(p0, p), equatorial = [normal[1], -normal[0], 0], inflection = cartesianCross(equatorial, normal); cartesianNormalizeInPlace(inflection); inflection = spherical(inflection); var delta = lambda - lambda2, sign = delta > 0 ? 1 : -1, lambdai = inflection[0] * degrees * sign, phii, antimeridian = abs(delta) > 180; if (antimeridian ^ (sign * lambda2 < lambdai && lambdai < sign * lambda)) { phii = inflection[1] * degrees; if (phii > phi1) phi1 = phii; } else if (lambdai = (lambdai + 360) % 360 - 180, antimeridian ^ (sign * lambda2 < lambdai && lambdai < sign * lambda)) { phii = -inflection[1] * degrees; if (phii < phi0) phi0 = phii; } else { if (phi < phi0) phi0 = phi; if (phi > phi1) phi1 = phi; } if (antimeridian) { if (lambda < lambda2) { if (angle(lambda0$1, lambda) > angle(lambda0$1, lambda1)) lambda1 = lambda; } else { if (angle(lambda, lambda1) > angle(lambda0$1, lambda1)) lambda0$1 = lambda; } } else { if (lambda1 >= lambda0$1) { if (lambda < lambda0$1) lambda0$1 = lambda; if (lambda > lambda1) lambda1 = lambda; } else { if (lambda > lambda2) { if (angle(lambda0$1, lambda) > angle(lambda0$1, lambda1)) lambda1 = lambda; } else { if (angle(lambda, lambda1) > angle(lambda0$1, lambda1)) lambda0$1 = lambda; } } } } else { ranges.push(range = [lambda0$1 = lambda, lambda1 = lambda]); } if (phi < phi0) phi0 = phi; if (phi > phi1) phi1 = phi; p0 = p, lambda2 = lambda; } function boundsLineStart() { boundsStream$1.point = linePoint; } function boundsLineEnd() { range[0] = lambda0$1, range[1] = lambda1; boundsStream$1.point = boundsPoint$1; p0 = null; } function boundsRingPoint(lambda, phi) { if (p0) { var delta = lambda - lambda2; deltaSum.add(abs(delta) > 180 ? delta + (delta > 0 ? 360 : -360) : delta); } else { lambda00$1 = lambda, phi00$1 = phi; } areaStream$1.point(lambda, phi); linePoint(lambda, phi); } function boundsRingStart() { areaStream$1.lineStart(); } function boundsRingEnd() { boundsRingPoint(lambda00$1, phi00$1); areaStream$1.lineEnd(); if (abs(deltaSum) > epsilon) lambda0$1 = -(lambda1 = 180); range[0] = lambda0$1, range[1] = lambda1; p0 = null; } // Finds the left-right distance between two longitudes. // This is almost the same as (lambda1 - lambda0 + 360°) % 360°, except that we want // the distance between ±180° to be 360°. function angle(lambda0, lambda1) { return (lambda1 -= lambda0) < 0 ? lambda1 + 360 : lambda1; } function rangeCompare(a, b) { return a[0] - b[0]; } function rangeContains(range, x) { return range[0] <= range[1] ? range[0] <= x && x <= range[1] : x < range[0] || range[1] < x; } function bounds(feature) { var i, n, a, b, merged, deltaMax, delta; phi1 = lambda1 = -(lambda0$1 = phi0 = Infinity); ranges = []; geoStream(feature, boundsStream$1); // First, sort ranges by their minimum longitudes. if (n = ranges.length) { ranges.sort(rangeCompare); // Then, merge any ranges that overlap. for (i = 1, a = ranges[0], merged = [a]; i < n; ++i) { b = ranges[i]; if (rangeContains(a, b[0]) || rangeContains(a, b[1])) { if (angle(a[0], b[1]) > angle(a[0], a[1])) a[1] = b[1]; if (angle(b[0], a[1]) > angle(a[0], a[1])) a[0] = b[0]; } else { merged.push(a = b); } } // Finally, find the largest gap between the merged ranges. // The final bounding box will be the inverse of this gap. for (deltaMax = -Infinity, n = merged.length - 1, i = 0, a = merged[n]; i <= n; a = b, ++i) { b = merged[i]; if ((delta = angle(a[1], b[0])) > deltaMax) deltaMax = delta, lambda0$1 = b[0], lambda1 = a[1]; } } ranges = range = null; return lambda0$1 === Infinity || phi0 === Infinity ? [[NaN, NaN], [NaN, NaN]] : [[lambda0$1, phi0], [lambda1, phi1]]; } var W0, W1, X0$1, Y0$1, Z0$1, X1$1, Y1$1, Z1$1, X2$1, Y2$1, Z2$1, lambda00, phi00, // first point x0$4, y0$4, z0; // previous point var centroidStream$1 = { sphere: noop, point: centroidPoint$1, lineStart: centroidLineStart$1, lineEnd: centroidLineEnd$1, polygonStart: function() { centroidStream$1.lineStart = centroidRingStart$1; centroidStream$1.lineEnd = centroidRingEnd$1; }, polygonEnd: function() { centroidStream$1.lineStart = centroidLineStart$1; centroidStream$1.lineEnd = centroidLineEnd$1; } }; // Arithmetic mean of Cartesian vectors. function centroidPoint$1(lambda, phi) { lambda *= radians, phi *= radians; var cosPhi = cos(phi); centroidPointCartesian(cosPhi * cos(lambda), cosPhi * sin(lambda), sin(phi)); } function centroidPointCartesian(x, y, z) { ++W0; X0$1 += (x - X0$1) / W0; Y0$1 += (y - Y0$1) / W0; Z0$1 += (z - Z0$1) / W0; } function centroidLineStart$1() { centroidStream$1.point = centroidLinePointFirst; } function centroidLinePointFirst(lambda, phi) { lambda *= radians, phi *= radians; var cosPhi = cos(phi); x0$4 = cosPhi * cos(lambda); y0$4 = cosPhi * sin(lambda); z0 = sin(phi); centroidStream$1.point = centroidLinePoint; centroidPointCartesian(x0$4, y0$4, z0); } function centroidLinePoint(lambda, phi) { lambda *= radians, phi *= radians; var cosPhi = cos(phi), x = cosPhi * cos(lambda), y = cosPhi * sin(lambda), z = sin(phi), w = atan2(sqrt((w = y0$4 * z - z0 * y) * w + (w = z0 * x - x0$4 * z) * w + (w = x0$4 * y - y0$4 * x) * w), x0$4 * x + y0$4 * y + z0 * z); W1 += w; X1$1 += w * (x0$4 + (x0$4 = x)); Y1$1 += w * (y0$4 + (y0$4 = y)); Z1$1 += w * (z0 + (z0 = z)); centroidPointCartesian(x0$4, y0$4, z0); } function centroidLineEnd$1() { centroidStream$1.point = centroidPoint$1; } // See J. E. Brock, The Inertia Tensor for a Spherical Triangle, // J. Applied Mechanics 42, 239 (1975). function centroidRingStart$1() { centroidStream$1.point = centroidRingPointFirst; } function centroidRingEnd$1() { centroidRingPoint(lambda00, phi00); centroidStream$1.point = centroidPoint$1; } function centroidRingPointFirst(lambda, phi) { lambda00 = lambda, phi00 = phi; lambda *= radians, phi *= radians; centroidStream$1.point = centroidRingPoint; var cosPhi = cos(phi); x0$4 = cosPhi * cos(lambda); y0$4 = cosPhi * sin(lambda); z0 = sin(phi); centroidPointCartesian(x0$4, y0$4, z0); } function centroidRingPoint(lambda, phi) { lambda *= radians, phi *= radians; var cosPhi = cos(phi), x = cosPhi * cos(lambda), y = cosPhi * sin(lambda), z = sin(phi), cx = y0$4 * z - z0 * y, cy = z0 * x - x0$4 * z, cz = x0$4 * y - y0$4 * x, m = hypot(cx, cy, cz), w = asin(m), // line weight = angle v = m && -w / m; // area weight multiplier X2$1.add(v * cx); Y2$1.add(v * cy); Z2$1.add(v * cz); W1 += w; X1$1 += w * (x0$4 + (x0$4 = x)); Y1$1 += w * (y0$4 + (y0$4 = y)); Z1$1 += w * (z0 + (z0 = z)); centroidPointCartesian(x0$4, y0$4, z0); } function centroid(object) { W0 = W1 = X0$1 = Y0$1 = Z0$1 = X1$1 = Y1$1 = Z1$1 = 0; X2$1 = new d3Array.Adder(); Y2$1 = new d3Array.Adder(); Z2$1 = new d3Array.Adder(); geoStream(object, centroidStream$1); var x = +X2$1, y = +Y2$1, z = +Z2$1, m = hypot(x, y, z); // If the area-weighted ccentroid is undefined, fall back to length-weighted ccentroid. if (m < epsilon2) { x = X1$1, y = Y1$1, z = Z1$1; // If the feature has zero length, fall back to arithmetic mean of point vectors. if (W1 < epsilon) x = X0$1, y = Y0$1, z = Z0$1; m = hypot(x, y, z); // If the feature still has an undefined ccentroid, then return. if (m < epsilon2) return [NaN, NaN]; } return [atan2(y, x) * degrees, asin(z / m) * degrees]; } function constant(x) { return function() { return x; }; } function compose(a, b) { function compose(x, y) { return x = a(x, y), b(x[0], x[1]); } if (a.invert && b.invert) compose.invert = function(x, y) { return x = b.invert(x, y), x && a.invert(x[0], x[1]); }; return compose; } function rotationIdentity(lambda, phi) { if (abs(lambda) > pi) lambda -= Math.round(lambda / tau) * tau; return [lambda, phi]; } rotationIdentity.invert = rotationIdentity; function rotateRadians(deltaLambda, deltaPhi, deltaGamma) { return (deltaLambda %= tau) ? (deltaPhi || deltaGamma ? compose(rotationLambda(deltaLambda), rotationPhiGamma(deltaPhi, deltaGamma)) : rotationLambda(deltaLambda)) : (deltaPhi || deltaGamma ? rotationPhiGamma(deltaPhi, deltaGamma) : rotationIdentity); } function forwardRotationLambda(deltaLambda) { return function(lambda, phi) { lambda += deltaLambda; if (abs(lambda) > pi) lambda -= Math.round(lambda / tau) * tau; return [lambda, phi]; }; } function rotationLambda(deltaLambda) { var rotation = forwardRotationLambda(deltaLambda); rotation.invert = forwardRotationLambda(-deltaLambda); return rotation; } function rotationPhiGamma(deltaPhi, deltaGamma) { var cosDeltaPhi = cos(deltaPhi), sinDeltaPhi = sin(deltaPhi), cosDeltaGamma = cos(deltaGamma), sinDeltaGamma = sin(deltaGamma); function rotation(lambda, phi) { var cosPhi = cos(phi), x = cos(lambda) * cosPhi, y = sin(lambda) * cosPhi, z = sin(phi), k = z * cosDeltaPhi + x * sinDeltaPhi; return [ atan2(y * cosDeltaGamma - k * sinDeltaGamma, x * cosDeltaPhi - z * sinDeltaPhi), asin(k * cosDeltaGamma + y * sinDeltaGamma) ]; } rotation.invert = function(lambda, phi) { var cosPhi = cos(phi), x = cos(lambda) * cosPhi, y = sin(lambda) * cosPhi, z = sin(phi), k = z * cosDeltaGamma - y * sinDeltaGamma; return [ atan2(y * cosDeltaGamma + z * sinDeltaGamma, x * cosDeltaPhi + k * sinDeltaPhi), asin(k * cosDeltaPhi - x * sinDeltaPhi) ]; }; return rotation; } function rotation(rotate) { rotate = rotateRadians(rotate[0] * radians, rotate[1] * radians, rotate.length > 2 ? rotate[2] * radians : 0); function forward(coordinates) { coordinates = rotate(coordinates[0] * radians, coordinates[1] * radians); return coordinates[0] *= degrees, coordinates[1] *= degrees, coordinates; } forward.invert = function(coordinates) { coordinates = rotate.invert(coordinates[0] * radians, coordinates[1] * radians); return coordinates[0] *= degrees, coordinates[1] *= degrees, coordinates; }; return forward; } // Generates a circle centered at [0°, 0°], with a given radius and precision. function circleStream(stream, radius, delta, direction, t0, t1) { if (!delta) return; var cosRadius = cos(radius), sinRadius = sin(radius), step = direction * delta; if (t0 == null) { t0 = radius + direction * tau; t1 = radius - step / 2; } else { t0 = circleRadius(cosRadius, t0); t1 = circleRadius(cosRadius, t1); if (direction > 0 ? t0 < t1 : t0 > t1) t0 += direction * tau; } for (var point, t = t0; direction > 0 ? t > t1 : t < t1; t -= step) { point = spherical([cosRadius, -sinRadius * cos(t), -sinRadius * sin(t)]); stream.point(point[0], point[1]); } } // Returns the signed angle of a cartesian point relative to [cosRadius, 0, 0]. function circleRadius(cosRadius, point) { point = cartesian(point), point[0] -= cosRadius; cartesianNormalizeInPlace(point); var radius = acos(-point[1]); return ((-point[2] < 0 ? -radius : radius) + tau - epsilon) % tau; } function circle() { var center = constant([0, 0]), radius = constant(90), precision = constant(6), ring, rotate, stream = {point: point}; function point(x, y) { ring.push(x = rotate(x, y)); x[0] *= degrees, x[1] *= degrees; } function circle() { var c = center.apply(this, arguments), r = radius.apply(this, arguments) * radians, p = precision.apply(this, arguments) * radians; ring = []; rotate = rotateRadians(-c[0] * radians, -c[1] * radians, 0).invert; circleStream(stream, r, p, 1); c = {type: "Polygon", coordinates: [ring]}; ring = rotate = null; return c; } circle.center = function(_) { return arguments.length ? (center = typeof _ === "function" ? _ : constant([+_[0], +_[1]]), circle) : center; }; circle.radius = function(_) { return arguments.length ? (radius = typeof _ === "function" ? _ : constant(+_), circle) : radius; }; circle.precision = function(_) { return arguments.length ? (precision = typeof _ === "function" ? _ : constant(+_), circle) : precision; }; return circle; } function clipBuffer() { var lines = [], line; return { point: function(x, y, m) { line.push([x, y, m]); }, lineStart: function() { lines.push(line = []); }, lineEnd: noop, rejoin: function() { if (lines.length > 1) lines.push(lines.pop().concat(lines.shift())); }, result: function() { var result = lines; lines = []; line = null; return result; } }; } function pointEqual(a, b) { return abs(a[0] - b[0]) < epsilon && abs(a[1] - b[1]) < epsilon; } function Intersection(point, points, other, entry) { this.x = point; this.z = points; this.o = other; // another intersection this.e = entry; // is an entry? this.v = false; // visited this.n = this.p = null; // next & previous } // A generalized polygon clipping algorithm: given a polygon that has been cut // into its visible line segments, and rejoins the segments by interpolating // along the clip edge. function clipRejoin(segments, compareIntersection, startInside, interpolate, stream) { var subject = [], clip = [], i, n; segments.forEach(function(segment) { if ((n = segment.length - 1) <= 0) return; var n, p0 = segment[0], p1 = segment[n], x; if (pointEqual(p0, p1)) { if (!p0[2] && !p1[2]) { stream.lineStart(); for (i = 0; i < n; ++i) stream.point((p0 = segment[i])[0], p0[1]); stream.lineEnd(); return; } // handle degenerate cases by moving the point p1[0] += 2 * epsilon; } subject.push(x = new Intersection(p0, segment, null, true)); clip.push(x.o = new Intersection(p0, null, x, false)); subject.push(x = new Intersection(p1, segment, null, false)); clip.push(x.o = new Intersection(p1, null, x, true)); }); if (!subject.length) return; clip.sort(compareIntersection); link(subject); link(clip); for (i = 0, n = clip.length; i < n; ++i) { clip[i].e = startInside = !startInside; } var start = subject[0], points, point; while (1) { // Find first unvisited intersection. var current = start, isSubject = true; while (current.v) if ((current = current.n) === start) return; points = current.z; stream.lineStart(); do { current.v = current.o.v = true; if (current.e) { if (isSubject) { for (i = 0, n = points.length; i < n; ++i) stream.point((point = points[i])[0], point[1]); } else { interpolate(current.x, current.n.x, 1, stream); } current = current.n; } else { if (isSubject) { points = current.p.z; for (i = points.length - 1; i >= 0; --i) stream.point((point = points[i])[0], point[1]); } else { interpolate(current.x, current.p.x, -1, stream); } current = current.p; } current = current.o; points = current.z; isSubject = !isSubject; } while (!current.v); stream.lineEnd(); } } function link(array) { if (!(n = array.length)) return; var n, i = 0, a = array[0], b; while (++i < n) { a.n = b = array[i]; b.p = a; a = b; } a.n = b = array[0]; b.p = a; } function longitude(point) { return abs(point[0]) <= pi ? point[0] : sign(point[0]) * ((abs(point[0]) + pi) % tau - pi); } function polygonContains(polygon, point) { var lambda = longitude(point), phi = point[1], sinPhi = sin(phi), normal = [sin(lambda), -cos(lambda), 0], angle = 0, winding = 0; var sum = new d3Array.Adder(); if (sinPhi === 1) phi = halfPi + epsilon; else if (sinPhi === -1) phi = -halfPi - epsilon; for (var i = 0, n = polygon.length; i < n; ++i) { if (!(m = (ring = polygon[i]).length)) continue; var ring, m, point0 = ring[m - 1], lambda0 = longitude(point0), phi0 = point0[1] / 2 + quarterPi, sinPhi0 = sin(phi0), cosPhi0 = cos(phi0); for (var j = 0; j < m; ++j, lambda0 = lambda1, sinPhi0 = sinPhi1, cosPhi0 = cosPhi1, point0 = point1) { var point1 = ring[j], lambda1 = longitude(point1), phi1 = point1[1] / 2 + quarterPi, sinPhi1 = sin(phi1), cosPhi1 = cos(phi1), delta = lambda1 - lambda0, sign = delta >= 0 ? 1 : -1, absDelta = sign * delta, antimeridian = absDelta > pi, k = sinPhi0 * sinPhi1; sum.add(atan2(k * sign * sin(absDelta), cosPhi0 * cosPhi1 + k * cos(absDelta))); angle += antimeridian ? delta + sign * tau : delta; // Are the longitudes either side of the point’s meridian (lambda), // and are the latitudes smaller than the parallel (phi)? if (antimeridian ^ lambda0 >= lambda ^ lambda1 >= lambda) { var arc = cartesianCross(cartesian(point0), cartesian(point1)); cartesianNormalizeInPlace(arc); var intersection = cartesianCross(normal, arc); cartesianNormalizeInPlace(intersection); var phiArc = (antimeridian ^ delta >= 0 ? -1 : 1) * asin(intersection[2]); if (phi > phiArc || phi === phiArc && (arc[0] || arc[1])) { winding += antimeridian ^ delta >= 0 ? 1 : -1; } } } } // First, determine whether the South pole is inside or outside: // // It is inside if: // * the polygon winds around it in a clockwise direction. // * the polygon does not (cumulatively) wind around it, but has a negative // (counter-clockwise) area. // // Second, count the (signed) number of times a segment crosses a lambda // from the point to the South pole. If it is zero, then the point is the // same side as the South pole. return (angle < -epsilon || angle < epsilon && sum < -epsilon2) ^ (winding & 1); } function clip(pointVisible, clipLine, interpolate, start) { return function(sink) { var line = clipLine(sink), ringBuffer = clipBuffer(), ringSink = clipLine(ringBuffer), polygonStarted = false, polygon, segments, ring; var clip = { point: point, lineStart: lineStart, lineEnd: lineEnd, polygonStart: function() { clip.point = pointRing; clip.lineStart = ringStart; clip.lineEnd = ringEnd; segments = []; polygon = []; }, polygonEnd: function() { clip.point = point; clip.lineStart = lineStart; clip.lineEnd = lineEnd; segments = d3Array.merge(segments); var startInside = polygonContains(polygon, start); if (segments.length) { if (!polygonStarted) sink.polygonStart(), polygonStarted = true; clipRejoin(segments, compareIntersection, startInside, interpolate, sink); } else if (startInside) { if (!polygonStarted) sink.polygonStart(), polygonStarted = true; sink.lineStart(); interpolate(null, null, 1, sink); sink.lineEnd(); } if (polygonStarted) sink.polygonEnd(), polygonStarted = false; segments = polygon = null; }, sphere: function() { sink.polygonStart(); sink.lineStart(); interpolate(null, null, 1, sink); sink.lineEnd(); sink.polygonEnd(); } }; function point(lambda, phi) { if (pointVisible(lambda, phi)) sink.point(lambda, phi); } function pointLine(lambda, phi) { line.point(lambda, phi); } function lineStart() { clip.point = pointLine; line.lineStart(); } function lineEnd() { clip.point = point; line.lineEnd(); } function pointRing(lambda, phi) { ring.push([lambda, phi]); ringSink.point(lambda, phi); } function ringStart() { ringSink.lineStart(); ring = []; } function ringEnd() { pointRing(ring[0][0], ring[0][1]); ringSink.lineEnd(); var clean = ringSink.clean(), ringSegments = ringBuffer.result(), i, n = ringSegments.length, m, segment, point; ring.pop(); polygon.push(ring); ring = null; if (!n) return; // No intersections. if (clean & 1) { segment = ringSegments[0]; if ((m = segment.length - 1) > 0) { if (!polygonStarted) sink.polygonStart(), polygonStarted = true; sink.lineStart(); for (i = 0; i < m; ++i) sink.point((point = segment[i])[0], point[1]); sink.lineEnd(); } return; } // Rejoin connected segments. // TODO reuse ringBuffer.rejoin()? if (n > 1 && clean & 2) ringSegments.push(ringSegments.pop().concat(ringSegments.shift())); segments.push(ringSegments.filter(validSegment)); } return clip; }; } function validSegment(segment) { return segment.length > 1; } // Intersections are sorted along the clip edge. For both antimeridian cutting // and circle clipping, the same comparison is used. function compareIntersection(a, b) { return ((a = a.x)[0] < 0 ? a[1] - halfPi - epsilon : halfPi - a[1]) - ((b = b.x)[0] < 0 ? b[1] - halfPi - epsilon : halfPi - b[1]); } var clipAntimeridian = clip( function() { return true; }, clipAntimeridianLine, clipAntimeridianInterpolate, [-pi, -halfPi] ); // Takes a line and cuts into visible segments. Return values: 0 - there were // intersections or the line was empty; 1 - no intersections; 2 - there were // intersections, and the first and last segments should be rejoined. function clipAntimeridianLine(stream) { var lambda0 = NaN, phi0 = NaN, sign0 = NaN, clean; // no intersections return { lineStart: function() { stream.lineStart(); clean = 1; }, point: function(lambda1, phi1) { var sign1 = lambda1 > 0 ? pi : -pi, delta = abs(lambda1 - lambda0); if (abs(delta - pi) < epsilon) { // line crosses a pole stream.point(lambda0, phi0 = (phi0 + phi1) / 2 > 0 ? halfPi : -halfPi); stream.point(sign0, phi0); stream.lineEnd(); stream.lineStart(); stream.point(sign1, phi0); stream.point(lambda1, phi0); clean = 0; } else if (sign0 !== sign1 && delta >= pi) { // line crosses antimeridian if (abs(lambda0 - sign0) < epsilon) lambda0 -= sign0 * epsilon; // handle degeneracies if (abs(lambda1 - sign1) < epsilon) lambda1 -= sign1 * epsilon; phi0 = clipAntimeridianIntersect(lambda0, phi0, lambda1, phi1); stream.point(sign0, phi0); stream.lineEnd(); stream.lineStart(); stream.point(sign1, phi0); clean = 0; } stream.point(lambda0 = lambda1, phi0 = phi1); sign0 = sign1; }, lineEnd: function() { stream.lineEnd(); lambda0 = phi0 = NaN; }, clean: function() { return 2 - clean; // if intersections, rejoin first and last segments } }; } function clipAntimeridianIntersect(lambda0, phi0, lambda1, phi1) { var cosPhi0, cosPhi1, sinLambda0Lambda1 = sin(lambda0 - lambda1); return abs(sinLambda0Lambda1) > epsilon ? atan((sin(phi0) * (cosPhi1 = cos(phi1)) * sin(lambda1) - sin(phi1) * (cosPhi0 = cos(phi0)) * sin(lambda0)) / (cosPhi0 * cosPhi1 * sinLambda0Lambda1)) : (phi0 + phi1) / 2; } function clipAntimeridianInterpolate(from, to, direction, stream) { var phi; if (from == null) { phi = direction * halfPi; stream.point(-pi, phi); stream.point(0, phi); stream.point(pi, phi); stream.point(pi, 0); stream.point(pi, -phi); stream.point(0, -phi); stream.point(-pi, -phi); stream.point(-pi, 0); stream.point(-pi, phi); } else if (abs(from[0] - to[0]) > epsilon) { var lambda = from[0] < to[0] ? pi : -pi; phi = direction * lambda / 2; stream.point(-lambda, phi); stream.point(0, phi); stream.point(lambda, phi); } else { stream.point(to[0], to[1]); } } function clipCircle(radius) { var cr = cos(radius), delta = 6 * radians, smallRadius = cr > 0, notHemisphere = abs(cr) > epsilon; // TODO optimise for this common case function interpolate(from, to, direction, stream) { circleStream(stream, radius, delta, direction, from, to); } function visible(lambda, phi) { return cos(lambda) * cos(phi) > cr; } // Takes a line and cuts into visible segments. Return values used for polygon // clipping: 0 - there were intersections or the line was empty; 1 - no // intersections 2 - there were intersections, and the first and last segments // should be rejoined. function clipLine(stream) { var point0, // previous point c0, // code for previous point v0, // visibility of previous point v00, // visibility of first point clean; // no intersections return { lineStart: function() { v00 = v0 = false; clean = 1; }, point: function(lambda, phi) { var point1 = [lambda, phi], point2, v = visible(lambda, phi), c = smallRadius ? v ? 0 : code(lambda, phi) : v ? code(lambda + (lambda < 0 ? pi : -pi), phi) : 0; if (!point0 && (v00 = v0 = v)) stream.lineStart(); if (v !== v0) { point2 = intersect(point0, point1); if (!point2 || pointEqual(point0, point2) || pointEqual(point1, point2)) point1[2] = 1; } if (v !== v0) { clean = 0; if (v) { // outside going in stream.lineStart(); point2 = intersect(point1, point0); stream.point(point2[0], point2[1]); } else { // inside going out point2 = intersect(point0, point1); stream.point(point2[0], point2[1], 2); stream.lineEnd(); } point0 = point2; } else if (notHemisphere && point0 && smallRadius ^ v) { var t; // If the codes for two points are different, or are both zero, // and there this segment intersects with the small circle. if (!(c & c0) && (t = intersect(point1, point0, true))) { clean = 0; if (smallRadius) { stream.lineStart(); stream.point(t[0][0], t[0][1]); stream.point(t[1][0], t[1][1]); stream.lineEnd(); } else { stream.point(t[1][0], t[1][1]); stream.lineEnd(); stream.lineStart(); stream.point(t[0][0], t[0][1], 3); } } } if (v && (!point0 || !pointEqual(point0, point1))) { stream.point(point1[0], point1[1]); } point0 = point1, v0 = v, c0 = c; }, lineEnd: function() { if (v0) stream.lineEnd(); point0 = null; }, // Rejoin first and last segments if there were intersections and the first // and last points were visible. clean: function() { return clean | ((v00 && v0) << 1); } }; } // Intersects the great circle between a and b with the clip circle. function intersect(a, b, two) { var pa = cartesian(a), pb = cartesian(b); // We have two planes, n1.p = d1 and n2.p = d2. // Find intersection line p(t) = c1 n1 + c2 n2 + t (n1 ⨯ n2). var n1 = [1, 0, 0], // normal n2 = cartesianCross(pa, pb), n2n2 = cartesianDot(n2, n2), n1n2 = n2[0], // cartesianDot(n1, n2), determinant = n2n2 - n1n2 * n1n2; // Two polar points. if (!determinant) return !two && a; var c1 = cr * n2n2 / determinant, c2 = -cr * n1n2 / determinant, n1xn2 = cartesianCross(n1, n2), A = cartesianScale(n1, c1), B = cartesianScale(n2, c2); cartesianAddInPlace(A, B); // Solve |p(t)|^2 = 1. var u = n1xn2, w = cartesianDot(A, u), uu = cartesianDot(u, u), t2 = w * w - uu * (cartesianDot(A, A) - 1); if (t2 < 0) return; var t = sqrt(t2), q = cartesianScale(u, (-w - t) / uu); cartesianAddInPlace(q, A); q = spherical(q); if (!two) return q; // Two intersection points. var lambda0 = a[0], lambda1 = b[0], phi0 = a[1], phi1 = b[1], z; if (lambda1 < lambda0) z = lambda0, lambda0 = lambda1, lambda1 = z; var delta = lambda1 - lambda0, polar = abs(delta - pi) < epsilon, meridian = polar || delta < epsilon; if (!polar && phi1 < phi0) z = phi0, phi0 = phi1, phi1 = z; // Check that the first point is between a and b. if (meridian ? polar ? phi0 + phi1 > 0 ^ q[1] < (abs(q[0] - lambda0) < epsilon ? phi0 : phi1) : phi0 <= q[1] && q[1] <= phi1 : delta > pi ^ (lambda0 <= q[0] && q[0] <= lambda1)) { var q1 = cartesianScale(u, (-w + t) / uu); cartesianAddInPlace(q1, A); return [q, spherical(q1)]; } } // Generates a 4-bit vector representing the location of a point relative to // the small circle's bounding box. function code(lambda, phi) { var r = smallRadius ? radius : pi - radius, code = 0; if (lambda < -r) code |= 1; // left else if (lambda > r) code |= 2; // right if (phi < -r) code |= 4; // below else if (phi > r) code |= 8; // above return code; } return clip(visible, clipLine, interpolate, smallRadius ? [0, -radius] : [-pi, radius - pi]); } function clipLine(a, b, x0, y0, x1, y1) { var ax = a[0], ay = a[1], bx = b[0], by = b[1], t0 = 0, t1 = 1, dx = bx - ax, dy = by - ay, r; r = x0 - ax; if (!dx && r > 0) return; r /= dx; if (dx < 0) { if (r < t0) return; if (r < t1) t1 = r; } else if (dx > 0) { if (r > t1) return; if (r > t0) t0 = r; } r = x1 - ax; if (!dx && r < 0) return; r /= dx; if (dx < 0) { if (r > t1) return; if (r > t0) t0 = r; } else if (dx > 0) { if (r < t0) return; if (r < t1) t1 = r; } r = y0 - ay; if (!dy && r > 0) return; r /= dy; if (dy < 0) { if (r < t0) return; if (r < t1) t1 = r; } else if (dy > 0) { if (r > t1) return; if (r > t0) t0 = r; } r = y1 - ay; if (!dy && r < 0) return; r /= dy; if (dy < 0) { if (r > t1) return; if (r > t0) t0 = r; } else if (dy > 0) { if (r < t0) return; if (r < t1) t1 = r; } if (t0 > 0) a[0] = ax + t0 * dx, a[1] = ay + t0 * dy; if (t1 < 1) b[0] = ax + t1 * dx, b[1] = ay + t1 * dy; return true; } var clipMax = 1e9, clipMin = -clipMax; // TODO Use d3-polygon’s polygonContains here for the ring check? // TODO Eliminate duplicate buffering in clipBuffer and polygon.push? function clipRectangle(x0, y0, x1, y1) { function visible(x, y) { return x0 <= x && x <= x1 && y0 <= y && y <= y1; } function interpolate(from, to, direction, stream) { var a = 0, a1 = 0; if (from == null || (a = corner(from, direction)) !== (a1 = corner(to, direction)) || comparePoint(from, to) < 0 ^ direction > 0) { do stream.point(a === 0 || a === 3 ? x0 : x1, a > 1 ? y1 : y0); while ((a = (a + direction + 4) % 4) !== a1); } else { stream.point(to[0], to[1]); } } function corner(p, direction) { return abs(p[0] - x0) < epsilon ? direction > 0 ? 0 : 3 : abs(p[0] - x1) < epsilon ? direction > 0 ? 2 : 1 : abs(p[1] - y0) < epsilon ? direction > 0 ? 1 : 0 : direction > 0 ? 3 : 2; // abs(p[1] - y1) < epsilon } function compareIntersection(a, b) { return comparePoint(a.x, b.x); } function comparePoint(a, b) { var ca = corner(a, 1), cb = corner(b, 1); return ca !== cb ? ca - cb : ca === 0 ? b[1] - a[1] : ca === 1 ? a[0] - b[0] : ca === 2 ? a[1] - b[1] : b[0] - a[0]; } return function(stream) { var activeStream = stream, bufferStream = clipBuffer(), segments, polygon, ring, x__, y__, v__, // first point x_, y_, v_, // previous point first, clean; var clipStream = { point: point, lineStart: lineStart, lineEnd: lineEnd, polygonStart: polygonStart, polygonEnd: polygonEnd }; function point(x, y) { if (visible(x, y)) activeStream.point(x, y); } function polygonInside() { var winding = 0; for (var i = 0, n = polygon.length; i < n; ++i) { for (var ring = polygon[i], j = 1, m = ring.length, point = ring[0], a0, a1, b0 = point[0], b1 = point[1]; j < m; ++j) { a0 = b0, a1 = b1, point = ring[j], b0 = point[0], b1 = point[1]; if (a1 <= y1) { if (b1 > y1 && (b0 - a0) * (y1 - a1) > (b1 - a1) * (x0 - a0)) ++winding; } else { if (b1 <= y1 && (b0 - a0) * (y1 - a1) < (b1 - a1) * (x0 - a0)) --winding; } } } return winding; } // Buffer geometry within a polygon and then clip it en masse. function polygonStart() { activeStream = bufferStream, segments = [], polygon = [], clean = true; } function polygonEnd() { var startInside = polygonInside(), cleanInside = clean && startInside, visible = (segments = d3Array.merge(segments)).length; if (cleanInside || visible) { stream.polygonStart(); if (cleanInside) { stream.lineStart(); interpolate(null, null, 1, stream); stream.lineEnd(); } if (visible) { clipRejoin(segments, compareIntersection, startInside, interpolate, stream); } stream.polygonEnd(); } activeStream = stream, segments = polygon = ring = null; } function lineStart() { clipStream.point = linePoint; if (polygon) polygon.push(ring = []); first = true; v_ = false; x_ = y_ = NaN; } // TODO rather than special-case polygons, simply handle them separately. // Ideally, coincident intersection points should be jittered to avoid // clipping issues. function lineEnd() { if (segments) { linePoint(x__, y__); if (v__ && v_) bufferStream.rejoin(); segments.push(bufferStream.result()); } clipStream.point = point; if (v_) activeStream.lineEnd(); } function linePoint(x, y) { var v = visible(x, y); if (polygon) ring.push([x, y]); if (first) { x__ = x, y__ = y, v__ = v; first = false; if (v) { activeStream.lineStart(); activeStream.point(x, y); } } else { if (v && v_) activeStream.point(x, y); else { var a = [x_ = Math.max(clipMin, Math.min(clipMax, x_)), y_ = Math.max(clipMin, Math.min(clipMax, y_))], b = [x = Math.max(clipMin, Math.min(clipMax, x)), y = Math.max(clipMin, Math.min(clipMax, y))]; if (clipLine(a, b, x0, y0, x1, y1)) { if (!v_) { activeStream.lineStart(); activeStream.point(a[0], a[1]); } activeStream.point(b[0], b[1]); if (!v) activeStream.lineEnd(); clean = false; } else if (v) { activeStream.lineStart(); activeStream.point(x, y); clean = false; } } } x_ = x, y_ = y, v_ = v; } return clipStream; }; } function extent() { var x0 = 0, y0 = 0, x1 = 960, y1 = 500, cache, cacheStream, clip; return clip = { stream: function(stream) { return cache && cacheStream === stream ? cache : cache = clipRectangle(x0, y0, x1, y1)(cacheStream = stream); }, extent: function(_) { return arguments.length ? (x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1], cache = cacheStream = null, clip) : [[x0, y0], [x1, y1]]; } }; } var lengthSum$1, lambda0, sinPhi0, cosPhi0; var lengthStream$1 = { sphere: noop, point: noop, lineStart: lengthLineStart, lineEnd: noop, polygonStart: noop, polygonEnd: noop }; function lengthLineStart() { lengthStream$1.point = lengthPointFirst$1; lengthStream$1.lineEnd = lengthLineEnd; } function lengthLineEnd() { lengthStream$1.point = lengthStream$1.lineEnd = noop; } function lengthPointFirst$1(lambda, phi) { lambda *= radians, phi *= radians; lambda0 = lambda, sinPhi0 = sin(phi), cosPhi0 = cos(phi); lengthStream$1.point = lengthPoint$1; } function lengthPoint$1(lambda, phi) { lambda *= radians, phi *= radians; var sinPhi = sin(phi), cosPhi = cos(phi), delta = abs(lambda - lambda0), cosDelta = cos(delta), sinDelta = sin(delta), x = cosPhi * sinDelta, y = cosPhi0 * sinPhi - sinPhi0 * cosPhi * cosDelta, z = sinPhi0 * sinPhi + cosPhi0 * cosPhi * cosDelta; lengthSum$1.add(atan2(sqrt(x * x + y * y), z)); lambda0 = lambda, sinPhi0 = sinPhi, cosPhi0 = cosPhi; } function length(object) { lengthSum$1 = new d3Array.Adder(); geoStream(object, lengthStream$1); return +lengthSum$1; } var coordinates = [null, null], object = {type: "LineString", coordinates: coordinates}; function distance(a, b) { coordinates[0] = a; coordinates[1] = b; return length(object); } var containsObjectType = { Feature: function(object, point) { return containsGeometry(object.geometry, point); }, FeatureCollection: function(object, point) { var features = object.features, i = -1, n = features.length; while (++i < n) if (containsGeometry(features[i].geometry, point)) return true; return false; } }; var containsGeometryType = { Sphere: function() { return true; }, Point: function(object, point) { return containsPoint(object.coordinates, point); }, MultiPoint: function(object, point) { var coordinates = object.coordinates, i = -1, n = coordinates.length; while (++i < n) if (containsPoint(coordinates[i], point)) return true; return false; }, LineString: function(object, point) { return containsLine(object.coordinates, point); }, MultiLineString: function(object, point) { var coordinates = object.coordinates, i = -1, n = coordinates.length; while (++i < n) if (containsLine(coordinates[i], point)) return true; return false; }, Polygon: function(object, point) { return containsPolygon(object.coordinates, point); }, MultiPolygon: function(object, point) { var coordinates = object.coordinates, i = -1, n = coordinates.length; while (++i < n) if (containsPolygon(coordinates[i], point)) return true; return false; }, GeometryCollection: function(object, point) { var geometries = object.geometries, i = -1, n = geometries.length; while (++i < n) if (containsGeometry(geometries[i], point)) return true; return false; } }; function containsGeometry(geometry, point) { return geometry && containsGeometryType.hasOwnProperty(geometry.type) ? containsGeometryType[geometry.type](geometry, point) : false; } function containsPoint(coordinates, point) { return distance(coordinates, point) === 0; } function containsLine(coordinates, point) { var ao, bo, ab; for (var i = 0, n = coordinates.length; i < n; i++) { bo = distance(coordinates[i], point); if (bo === 0) return true; if (i > 0) { ab = distance(coordinates[i], coordinates[i - 1]); if ( ab > 0 && ao <= ab && bo <= ab && (ao + bo - ab) * (1 - Math.pow((ao - bo) / ab, 2)) < epsilon2 * ab ) return true; } ao = bo; } return false; } function containsPolygon(coordinates, point) { return !!polygonContains(coordinates.map(ringRadians), pointRadians(point)); } function ringRadians(ring) { return ring = ring.map(pointRadians), ring.pop(), ring; } function pointRadians(point) { return [point[0] * radians, point[1] * radians]; } function contains(object, point) { return (object && containsObjectType.hasOwnProperty(object.type) ? containsObjectType[object.type] : containsGeometry)(object, point); } function graticuleX(y0, y1, dy) { var y = d3Array.range(y0, y1 - epsilon, dy).concat(y1); return function(x) { return y.map(function(y) { return [x, y]; }); }; } function graticuleY(x0, x1, dx) { var x = d3Array.range(x0, x1 - epsilon, dx).concat(x1); return function(y) { return x.map(function(x) { return [x, y]; }); }; } function graticule() { var x1, x0, X1, X0, y1, y0, Y1, Y0, dx = 10, dy = dx, DX = 90, DY = 360, x, y, X, Y, precision = 2.5; function graticule() { return {type: "MultiLineString", coordinates: lines()}; } function lines() { return d3Array.range(ceil(X0 / DX) * DX, X1, DX).map(X) .concat(d3Array.range(ceil(Y0 / DY) * DY, Y1, DY).map(Y)) .concat(d3Array.range(ceil(x0 / dx) * dx, x1, dx).filter(function(x) { return abs(x % DX) > epsilon; }).map(x)) .concat(d3Array.range(ceil(y0 / dy) * dy, y1, dy).filter(function(y) { return abs(y % DY) > epsilon; }).map(y)); } graticule.lines = function() { return lines().map(function(coordinates) { return {type: "LineString", coordinates: coordinates}; }); }; graticule.outline = function() { return { type: "Polygon", coordinates: [ X(X0).concat( Y(Y1).slice(1), X(X1).reverse().slice(1), Y(Y0).reverse().slice(1)) ] }; }; graticule.extent = function(_) { if (!arguments.length) return graticule.extentMinor(); return graticule.extentMajor(_).extentMinor(_); }; graticule.extentMajor = function(_) { if (!arguments.length) return [[X0, Y0], [X1, Y1]]; X0 = +_[0][0], X1 = +_[1][0]; Y0 = +_[0][1], Y1 = +_[1][1]; if (X0 > X1) _ = X0, X0 = X1, X1 = _; if (Y0 > Y1) _ = Y0, Y0 = Y1, Y1 = _; return graticule.precision(precision); }; graticule.extentMinor = function(_) { if (!arguments.length) return [[x0, y0], [x1, y1]]; x0 = +_[0][0], x1 = +_[1][0]; y0 = +_[0][1], y1 = +_[1][1]; if (x0 > x1) _ = x0, x0 = x1, x1 = _; if (y0 > y1) _ = y0, y0 = y1, y1 = _; return graticule.precision(precision); }; graticule.step = function(_) { if (!arguments.length) return graticule.stepMinor(); return graticule.stepMajor(_).stepMinor(_); }; graticule.stepMajor = function(_) { if (!arguments.length) return [DX, DY]; DX = +_[0], DY = +_[1]; return graticule; }; graticule.stepMinor = function(_) { if (!arguments.length) return [dx, dy]; dx = +_[0], dy = +_[1]; return graticule; }; graticule.precision = function(_) { if (!arguments.length) return precision; precision = +_; x = graticuleX(y0, y1, 90); y = graticuleY(x0, x1, precision); X = graticuleX(Y0, Y1, 90); Y = graticuleY(X0, X1, precision); return graticule; }; return graticule .extentMajor([[-180, -90 + epsilon], [180, 90 - epsilon]]) .extentMinor([[-180, -80 - epsilon], [180, 80 + epsilon]]); } function graticule10() { return graticule()(); } function interpolate(a, b) { var x0 = a[0] * radians, y0 = a[1] * radians, x1 = b[0] * radians, y1 = b[1] * radians, cy0 = cos(y0), sy0 = sin(y0), cy1 = cos(y1), sy1 = sin(y1), kx0 = cy0 * cos(x0), ky0 = cy0 * sin(x0), kx1 = cy1 * cos(x1), ky1 = cy1 * sin(x1), d = 2 * asin(sqrt(haversin(y1 - y0) + cy0 * cy1 * haversin(x1 - x0))), k = sin(d); var interpolate = d ? function(t) { var B = sin(t *= d) / k, A = sin(d - t) / k, x = A * kx0 + B * kx1, y = A * ky0 + B * ky1, z = A * sy0 + B * sy1; return [ atan2(y, x) * degrees, atan2(z, sqrt(x * x + y * y)) * degrees ]; } : function() { return [x0 * degrees, y0 * degrees]; }; interpolate.distance = d; return interpolate; } var identity$1 = x => x; var areaSum = new d3Array.Adder(), areaRingSum = new d3Array.Adder(), x00$2, y00$2, x0$3, y0$3; var areaStream = { point: noop, lineStart: noop, lineEnd: noop, polygonStart: function() { areaStream.lineStart = areaRingStart; areaStream.lineEnd = areaRingEnd; }, polygonEnd: function() { areaStream.lineStart = areaStream.lineEnd = areaStream.point = noop; areaSum.add(abs(areaRingSum)); areaRingSum = new d3Array.Adder(); }, result: function() { var area = areaSum / 2; areaSum = new d3Array.Adder(); return area; } }; function areaRingStart() { areaStream.point = areaPointFirst; } function areaPointFirst(x, y) { areaStream.point = areaPoint; x00$2 = x0$3 = x, y00$2 = y0$3 = y; } function areaPoint(x, y) { areaRingSum.add(y0$3 * x - x0$3 * y); x0$3 = x, y0$3 = y; } function areaRingEnd() { areaPoint(x00$2, y00$2); } var x0$2 = Infinity, y0$2 = x0$2, x1 = -x0$2, y1 = x1; var boundsStream = { point: boundsPoint, lineStart: noop, lineEnd: noop, polygonStart: noop, polygonEnd: noop, result: function() { var bounds = [[x0$2, y0$2], [x1, y1]]; x1 = y1 = -(y0$2 = x0$2 = Infinity); return bounds; } }; function boundsPoint(x, y) { if (x < x0$2) x0$2 = x; if (x > x1) x1 = x; if (y < y0$2) y0$2 = y; if (y > y1) y1 = y; } // TODO Enforce positive area for exterior, negative area for interior? var X0 = 0, Y0 = 0, Z0 = 0, X1 = 0, Y1 = 0, Z1 = 0, X2 = 0, Y2 = 0, Z2 = 0, x00$1, y00$1, x0$1, y0$1; var centroidStream = { point: centroidPoint, lineStart: centroidLineStart, lineEnd: centroidLineEnd, polygonStart: function() { centroidStream.lineStart = centroidRingStart; centroidStream.lineEnd = centroidRingEnd; }, polygonEnd: function() { centroidStream.point = centroidPoint; centroidStream.lineStart = centroidLineStart; centroidStream.lineEnd = centroidLineEnd; }, result: function() { var centroid = Z2 ? [X2 / Z2, Y2 / Z2] : Z1 ? [X1 / Z1, Y1 / Z1] : Z0 ? [X0 / Z0, Y0 / Z0] : [NaN, NaN]; X0 = Y0 = Z0 = X1 = Y1 = Z1 = X2 = Y2 = Z2 = 0; return centroid; } }; function centroidPoint(x, y) { X0 += x; Y0 += y; ++Z0; } function centroidLineStart() { centroidStream.point = centroidPointFirstLine; } function centroidPointFirstLine(x, y) { centroidStream.point = centroidPointLine; centroidPoint(x0$1 = x, y0$1 = y); } function centroidPointLine(x, y) { var dx = x - x0$1, dy = y - y0$1, z = sqrt(dx * dx + dy * dy); X1 += z * (x0$1 + x) / 2; Y1 += z * (y0$1 + y) / 2; Z1 += z; centroidPoint(x0$1 = x, y0$1 = y); } function centroidLineEnd() { centroidStream.point = centroidPoint; } function centroidRingStart() { centroidStream.point = centroidPointFirstRing; } function centroidRingEnd() { centroidPointRing(x00$1, y00$1); } function centroidPointFirstRing(x, y) { centroidStream.point = centroidPointRing; centroidPoint(x00$1 = x0$1 = x, y00$1 = y0$1 = y); } function centroidPointRing(x, y) { var dx = x - x0$1, dy = y - y0$1, z = sqrt(dx * dx + dy * dy); X1 += z * (x0$1 + x) / 2; Y1 += z * (y0$1 + y) / 2; Z1 += z; z = y0$1 * x - x0$1 * y; X2 += z * (x0$1 + x); Y2 += z * (y0$1 + y); Z2 += z * 3; centroidPoint(x0$1 = x, y0$1 = y); } function PathContext(context) { this._context = context; } PathContext.prototype = { _radius: 4.5, pointRadius: function(_) { return this._radius = _, this; }, polygonStart: function() { this._line = 0; }, polygonEnd: function() { this._line = NaN; }, lineStart: function() { this._point = 0; }, lineEnd: function() { if (this._line === 0) this._context.closePath(); this._point = NaN; }, point: function(x, y) { switch (this._point) { case 0: { this._context.moveTo(x, y); this._point = 1; break; } case 1: { this._context.lineTo(x, y); break; } default: { this._context.moveTo(x + this._radius, y); this._context.arc(x, y, this._radius, 0, tau); break; } } }, result: noop }; var lengthSum = new d3Array.Adder(), lengthRing, x00, y00, x0, y0; var lengthStream = { point: noop, lineStart: function() { lengthStream.point = lengthPointFirst; }, lineEnd: function() { if (lengthRing) lengthPoint(x00, y00); lengthStream.point = noop; }, polygonStart: function() { lengthRing = true; }, polygonEnd: function() { lengthRing = null; }, result: function() { var length = +lengthSum; lengthSum = new d3Array.Adder(); return length; } }; function lengthPointFirst(x, y) { lengthStream.point = lengthPoint; x00 = x0 = x, y00 = y0 = y; } function lengthPoint(x, y) { x0 -= x, y0 -= y; lengthSum.add(sqrt(x0 * x0 + y0 * y0)); x0 = x, y0 = y; } // Simple caching for constant-radius points. let cacheDigits, cacheAppend, cacheRadius, cacheCircle; class PathString { constructor(digits) { this._append = digits == null ? append : appendRound(digits); this._radius = 4.5; this._ = ""; } pointRadius(_) { this._radius = +_; return this; } polygonStart() { this._line = 0; } polygonEnd() { this._line = NaN; } lineStart() { this._point = 0; } lineEnd() { if (this._line === 0) this._ += "Z"; this._point = NaN; } point(x, y) { switch (this._point) { case 0: { this._append`M${x},${y}`; this._point = 1; break; } case 1: { this._append`L${x},${y}`; break; } default: { this._append`M${x},${y}`; if (this._radius !== cacheRadius || this._append !== cacheAppend) { const r = this._radius; const s = this._; this._ = ""; // stash the old string so we can cache the circle path fragment this._append`m0,${r}a${r},${r} 0 1,1 0,${-2 * r}a${r},${r} 0 1,1 0,${2 * r}z`; cacheRadius = r; cacheAppend = this._append; cacheCircle = this._; this._ = s; } this._ += cacheCircle; break; } } } result() { const result = this._; this._ = ""; return result.length ? result : null; } } function append(strings) { let i = 1; this._ += strings[0]; for (const j = strings.length; i < j; ++i) { this._ += arguments[i] + strings[i]; } } function appendRound(digits) { const d = Math.floor(digits); if (!(d >= 0)) throw new RangeError(`invalid digits: ${digits}`); if (d > 15) return append; if (d !== cacheDigits) { const k = 10 ** d; cacheDigits = d; cacheAppend = function append(strings) { let i = 1; this._ += strings[0]; for (const j = strings.length; i < j; ++i) { this._ += Math.round(arguments[i] * k) / k + strings[i]; } }; } return cacheAppend; } function index(projection, context) { let digits = 3, pointRadius = 4.5, projectionStream, contextStream; function path(object) { if (object) { if (typeof pointRadius === "function") contextStream.pointRadius(+pointRadius.apply(this, arguments)); geoStream(object, projectionStream(contextStream)); } return contextStream.result(); } path.area = function(object) { geoStream(object, projectionStream(areaStream)); return areaStream.result(); }; path.measure = function(object) { geoStream(object, projectionStream(lengthStream)); return lengthStream.result(); }; path.bounds = function(object) { geoStream(object, projectionStream(boundsStream)); return boundsStream.result(); }; path.centroid = function(object) { geoStream(object, projectionStream(centroidStream)); return centroidStream.result(); }; path.projection = function(_) { if (!arguments.length) return projection; projectionStream = _ == null ? (projection = null, identity$1) : (projection = _).stream; return path; }; path.context = function(_) { if (!arguments.length) return context; contextStream = _ == null ? (context = null, new PathString(digits)) : new PathContext(context = _); if (typeof pointRadius !== "function") contextStream.pointRadius(pointRadius); return path; }; path.pointRadius = function(_) { if (!arguments.length) return pointRadius; pointRadius = typeof _ === "function" ? _ : (contextStream.pointRadius(+_), +_); return path; }; path.digits = function(_) { if (!arguments.length) return digits; if (_ == null) digits = null; else { const d = Math.floor(_); if (!(d >= 0)) throw new RangeError(`invalid digits: ${_}`); digits = d; } if (context === null) contextStream = new PathString(digits); return path; }; return path.projection(projection).digits(digits).context(context); } function transform(methods) { return { stream: transformer(methods) }; } function transformer(methods) { return function(stream) { var s = new TransformStream; for (var key in methods) s[key] = methods[key]; s.stream = stream; return s; }; } function TransformStream() {} TransformStream.prototype = { constructor: TransformStream, point: function(x, y) { this.stream.point(x, y); }, sphere: function() { this.stream.sphere(); }, lineStart: function() { this.stream.lineStart(); }, lineEnd: function() { this.stream.lineEnd(); }, polygonStart: function() { this.stream.polygonStart(); }, polygonEnd: function() { this.stream.polygonEnd(); } }; function fit(projection, fitBounds, object) { var clip = projection.clipExtent && projection.clipExtent(); projection.scale(150).translate([0, 0]); if (clip != null) projection.clipExtent(null); geoStream(object, projection.stream(boundsStream)); fitBounds(boundsStream.result()); if (clip != null) projection.clipExtent(clip); return projection; } function fitExtent(projection, extent, object) { return fit(projection, function(b) { var w = extent[1][0] - extent[0][0], h = extent[1][1] - extent[0][1], k = Math.min(w / (b[1][0] - b[0][0]), h / (b[1][1] - b[0][1])), x = +extent[0][0] + (w - k * (b[1][0] + b[0][0])) / 2, y = +extent[0][1] + (h - k * (b[1][1] + b[0][1])) / 2; projection.scale(150 * k).translate([x, y]); }, object); } function fitSize(projection, size, object) { return fitExtent(projection, [[0, 0], size], object); } function fitWidth(projection, width, object) { return fit(projection, function(b) { var w = +width, k = w / (b[1][0] - b[0][0]), x = (w - k * (b[1][0] + b[0][0])) / 2, y = -k * b[0][1]; projection.scale(150 * k).translate([x, y]); }, object); } function fitHeight(projection, height, object) { return fit(projection, function(b) { var h = +height, k = h / (b[1][1] - b[0][1]), x = -k * b[0][0], y = (h - k * (b[1][1] + b[0][1])) / 2; projection.scale(150 * k).translate([x, y]); }, object); } var maxDepth = 16, // maximum depth of subdivision cosMinDistance = cos(30 * radians); // cos(minimum angular distance) function resample(project, delta2) { return +delta2 ? resample$1(project, delta2) : resampleNone(project); } function resampleNone(project) { return transformer({ point: function(x, y) { x = project(x, y); this.stream.point(x[0], x[1]); } }); } function resample$1(project, delta2) { function resampleLineTo(x0, y0, lambda0, a0, b0, c0, x1, y1, lambda1, a1, b1, c1, depth, stream) { var dx = x1 - x0, dy = y1 - y0, d2 = dx * dx + dy * dy; if (d2 > 4 * delta2 && depth--) { var a = a0 + a1, b = b0 + b1, c = c0 + c1, m = sqrt(a * a + b * b + c * c), phi2 = asin(c /= m), lambda2 = abs(abs(c) - 1) < epsilon || abs(lambda0 - lambda1) < epsilon ? (lambda0 + lambda1) / 2 : atan2(b, a), p = project(lambda2, phi2), x2 = p[0], y2 = p[1], dx2 = x2 - x0, dy2 = y2 - y0, dz = dy * dx2 - dx * dy2; if (dz * dz / d2 > delta2 // perpendicular projected distance || abs((dx * dx2 + dy * dy2) / d2 - 0.5) > 0.3 // midpoint close to an end || a0 * a1 + b0 * b1 + c0 * c1 < cosMinDistance) { // angular distance resampleLineTo(x0, y0, lambda0, a0, b0, c0, x2, y2, lambda2, a /= m, b /= m, c, depth, stream); stream.point(x2, y2); resampleLineTo(x2, y2, lambda2, a, b, c, x1, y1, lambda1, a1, b1, c1, depth, stream); } } } return function(stream) { var lambda00, x00, y00, a00, b00, c00, // first point lambda0, x0, y0, a0, b0, c0; // previous point var resampleStream = { point: point, lineStart: lineStart, lineEnd: lineEnd, polygonStart: function() { stream.polygonStart(); resampleStream.lineStart = ringStart; }, polygonEnd: function() { stream.polygonEnd(); resampleStream.lineStart = lineStart; } }; function point(x, y) { x = project(x, y); stream.point(x[0], x[1]); } function lineStart() { x0 = NaN; resampleStream.point = linePoint; stream.lineStart(); } function linePoint(lambda, phi) { var c = cartesian([lambda, phi]), p = project(lambda, phi); resampleLineTo(x0, y0, lambda0, a0, b0, c0, x0 = p[0], y0 = p[1], lambda0 = lambda, a0 = c[0], b0 = c[1], c0 = c[2], maxDepth, stream); stream.point(x0, y0); } function lineEnd() { resampleStream.point = point; stream.lineEnd(); } function ringStart() { lineStart(); resampleStream.point = ringPoint; resampleStream.lineEnd = ringEnd; } function ringPoint(lambda, phi) { linePoint(lambda00 = lambda, phi), x00 = x0, y00 = y0, a00 = a0, b00 = b0, c00 = c0; resampleStream.point = linePoint; } function ringEnd() { resampleLineTo(x0, y0, lambda0, a0, b0, c0, x00, y00, lambda00, a00, b00, c00, maxDepth, stream); resampleStream.lineEnd = lineEnd; lineEnd(); } return resampleStream; }; } var transformRadians = transformer({ point: function(x, y) { this.stream.point(x * radians, y * radians); } }); function transformRotate(rotate) { return transformer({ point: function(x, y) { var r = rotate(x, y); return this.stream.point(r[0], r[1]); } }); } function scaleTranslate(k, dx, dy, sx, sy) { function transform(x, y) { x *= sx; y *= sy; return [dx + k * x, dy - k * y]; } transform.invert = function(x, y) { return [(x - dx) / k * sx, (dy - y) / k * sy]; }; return transform; } function scaleTranslateRotate(k, dx, dy, sx, sy, alpha) { if (!alpha) return scaleTranslate(k, dx, dy, sx, sy); var cosAlpha = cos(alpha), sinAlpha = sin(alpha), a = cosAlpha * k, b = sinAlpha * k, ai = cosAlpha / k, bi = sinAlpha / k, ci = (sinAlpha * dy - cosAlpha * dx) / k, fi = (sinAlpha * dx + cosAlpha * dy) / k; function transform(x, y) { x *= sx; y *= sy; return [a * x - b * y + dx, dy - b * x - a * y]; } transform.invert = function(x, y) { return [sx * (ai * x - bi * y + ci), sy * (fi - bi * x - ai * y)]; }; return transform; } function projection(project) { return projectionMutator(function() { return project; })(); } function projectionMutator(projectAt) { var project, k = 150, // scale x = 480, y = 250, // translate lambda = 0, phi = 0, // center deltaLambda = 0, deltaPhi = 0, deltaGamma = 0, rotate, // pre-rotate alpha = 0, // post-rotate angle sx = 1, // reflectX sy = 1, // reflectX theta = null, preclip = clipAntimeridian, // pre-clip angle x0 = null, y0, x1, y1, postclip = identity$1, // post-clip extent delta2 = 0.5, // precision projectResample, projectTransform, projectRotateTransform, cache, cacheStream; function projection(point) { return projectRotateTransform(point[0] * radians, point[1] * radians); } function invert(point) { point = projectRotateTransform.invert(point[0], point[1]); return point && [point[0] * degrees, point[1] * degrees]; } projection.stream = function(stream) { return cache && cacheStream === stream ? cache : cache = transformRadians(transformRotate(rotate)(preclip(projectResample(postclip(cacheStream = stream))))); }; projection.preclip = function(_) { return arguments.length ? (preclip = _, theta = undefined, reset()) : preclip; }; projection.postclip = function(_) { return arguments.length ? (postclip = _, x0 = y0 = x1 = y1 = null, reset()) : postclip; }; projection.clipAngle = function(_) { return arguments.length ? (preclip = +_ ? clipCircle(theta = _ * radians) : (theta = null, clipAntimeridian), reset()) : theta * degrees; }; projection.clipExtent = function(_) { return arguments.length ? (postclip = _ == null ? (x0 = y0 = x1 = y1 = null, identity$1) : clipRectangle(x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1]), reset()) : x0 == null ? null : [[x0, y0], [x1, y1]]; }; projection.scale = function(_) { return arguments.length ? (k = +_, recenter()) : k; }; projection.translate = function(_) { return arguments.length ? (x = +_[0], y = +_[1], recenter()) : [x, y]; }; projection.center = function(_) { return arguments.length ? (lambda = _[0] % 360 * radians, phi = _[1] % 360 * radians, recenter()) : [lambda * degrees, phi * degrees]; }; projection.rotate = function(_) { return arguments.length ? (deltaLambda = _[0] % 360 * radians, deltaPhi = _[1] % 360 * radians, deltaGamma = _.length > 2 ? _[2] % 360 * radians : 0, recenter()) : [deltaLambda * degrees, deltaPhi * degrees, deltaGamma * degrees]; }; projection.angle = function(_) { return arguments.length ? (alpha = _ % 360 * radians, recenter()) : alpha * degrees; }; projection.reflectX = function(_) { return arguments.length ? (sx = _ ? -1 : 1, recenter()) : sx < 0; }; projection.reflectY = function(_) { return arguments.length ? (sy = _ ? -1 : 1, recenter()) : sy < 0; }; projection.precision = function(_) { return arguments.length ? (projectResample = resample(projectTransform, delta2 = _ * _), reset()) : sqrt(delta2); }; projection.fitExtent = function(extent, object) { return fitExtent(projection, extent, object); }; projection.fitSize = function(size, object) { return fitSize(projection, size, object); }; projection.fitWidth = function(width, object) { return fitWidth(projection, width, object); }; projection.fitHeight = function(height, object) { return fitHeight(projection, height, object); }; function recenter() { var center = scaleTranslateRotate(k, 0, 0, sx, sy, alpha).apply(null, project(lambda, phi)), transform = scaleTranslateRotate(k, x - center[0], y - center[1], sx, sy, alpha); rotate = rotateRadians(deltaLambda, deltaPhi, deltaGamma); projectTransform = compose(project, transform); projectRotateTransform = compose(rotate, projectTransform); projectResample = resample(projectTransform, delta2); return reset(); } function reset() { cache = cacheStream = null; return projection; } return function() { project = projectAt.apply(this, arguments); projection.invert = project.invert && invert; return recenter(); }; } function conicProjection(projectAt) { var phi0 = 0, phi1 = pi / 3, m = projectionMutator(projectAt), p = m(phi0, phi1); p.parallels = function(_) { return arguments.length ? m(phi0 = _[0] * radians, phi1 = _[1] * radians) : [phi0 * degrees, phi1 * degrees]; }; return p; } function cylindricalEqualAreaRaw(phi0) { var cosPhi0 = cos(phi0); function forward(lambda, phi) { return [lambda * cosPhi0, sin(phi) / cosPhi0]; } forward.invert = function(x, y) { return [x / cosPhi0, asin(y * cosPhi0)]; }; return forward; } function conicEqualAreaRaw(y0, y1) { var sy0 = sin(y0), n = (sy0 + sin(y1)) / 2; // Are the parallels symmetrical around the Equator? if (abs(n) < epsilon) return cylindricalEqualAreaRaw(y0); var c = 1 + sy0 * (2 * n - sy0), r0 = sqrt(c) / n; function project(x, y) { var r = sqrt(c - 2 * n * sin(y)) / n; return [r * sin(x *= n), r0 - r * cos(x)]; } project.invert = function(x, y) { var r0y = r0 - y, l = atan2(x, abs(r0y)) * sign(r0y); if (r0y * n < 0) l -= pi * sign(x) * sign(r0y); return [l / n, asin((c - (x * x + r0y * r0y) * n * n) / (2 * n))]; }; return project; } function conicEqualArea() { return conicProjection(conicEqualAreaRaw) .scale(155.424) .center([0, 33.6442]); } function albers() { return conicEqualArea() .parallels([29.5, 45.5]) .scale(1070) .translate([480, 250]) .rotate([96, 0]) .center([-0.6, 38.7]); } // The projections must have mutually exclusive clip regions on the sphere, // as this will avoid emitting interleaving lines and polygons. function multiplex(streams) { var n = streams.length; return { point: function(x, y) { var i = -1; while (++i < n) streams[i].point(x, y); }, sphere: function() { var i = -1; while (++i < n) streams[i].sphere(); }, lineStart: function() { var i = -1; while (++i < n) streams[i].lineStart(); }, lineEnd: function() { var i = -1; while (++i < n) streams[i].lineEnd(); }, polygonStart: function() { var i = -1; while (++i < n) streams[i].polygonStart(); }, polygonEnd: function() { var i = -1; while (++i < n) streams[i].polygonEnd(); } }; } // A composite projection for the United States, configured by default for // 960×500. The projection also works quite well at 960×600 if you change the // scale to 1285 and adjust the translate accordingly. The set of standard // parallels for each region comes from USGS, which is published here: // http://egsc.usgs.gov/isb/pubs/MapProjections/projections.html#albers function albersUsa() { var cache, cacheStream, lower48 = albers(), lower48Point, alaska = conicEqualArea().rotate([154, 0]).center([-2, 58.5]).parallels([55, 65]), alaskaPoint, // EPSG:3338 hawaii = conicEqualArea().rotate([157, 0]).center([-3, 19.9]).parallels([8, 18]), hawaiiPoint, // ESRI:102007 point, pointStream = {point: function(x, y) { point = [x, y]; }}; function albersUsa(coordinates) { var x = coordinates[0], y = coordinates[1]; return point = null, (lower48Point.point(x, y), point) || (alaskaPoint.point(x, y), point) || (hawaiiPoint.point(x, y), point); } albersUsa.invert = function(coordinates) { var k = lower48.scale(), t = lower48.translate(), x = (coordinates[0] - t[0]) / k, y = (coordinates[1] - t[1]) / k; return (y >= 0.120 && y < 0.234 && x >= -0.425 && x < -0.214 ? alaska : y >= 0.166 && y < 0.234 && x >= -0.214 && x < -0.115 ? hawaii : lower48).invert(coordinates); }; albersUsa.stream = function(stream) { return cache && cacheStream === stream ? cache : cache = multiplex([lower48.stream(cacheStream = stream), alaska.stream(stream), hawaii.stream(stream)]); }; albersUsa.precision = function(_) { if (!arguments.length) return lower48.precision(); lower48.precision(_), alaska.precision(_), hawaii.precision(_); return reset(); }; albersUsa.scale = function(_) { if (!arguments.length) return lower48.scale(); lower48.scale(_), alaska.scale(_ * 0.35), hawaii.scale(_); return albersUsa.translate(lower48.translate()); }; albersUsa.translate = function(_) { if (!arguments.length) return lower48.translate(); var k = lower48.scale(), x = +_[0], y = +_[1]; lower48Point = lower48 .translate(_) .clipExtent([[x - 0.455 * k, y - 0.238 * k], [x + 0.455 * k, y + 0.238 * k]]) .stream(pointStream); alaskaPoint = alaska .translate([x - 0.307 * k, y + 0.201 * k]) .clipExtent([[x - 0.425 * k + epsilon, y + 0.120 * k + epsilon], [x - 0.214 * k - epsilon, y + 0.234 * k - epsilon]]) .stream(pointStream); hawaiiPoint = hawaii .translate([x - 0.205 * k, y + 0.212 * k]) .clipExtent([[x - 0.214 * k + epsilon, y + 0.166 * k + epsilon], [x - 0.115 * k - epsilon, y + 0.234 * k - epsilon]]) .stream(pointStream); return reset(); }; albersUsa.fitExtent = function(extent, object) { return fitExtent(albersUsa, extent, object); }; albersUsa.fitSize = function(size, object) { return fitSize(albersUsa, size, object); }; albersUsa.fitWidth = function(width, object) { return fitWidth(albersUsa, width, object); }; albersUsa.fitHeight = function(height, object) { return fitHeight(albersUsa, height, object); }; function reset() { cache = cacheStream = null; return albersUsa; } return albersUsa.scale(1070); } function azimuthalRaw(scale) { return function(x, y) { var cx = cos(x), cy = cos(y), k = scale(cx * cy); if (k === Infinity) return [2, 0]; return [ k * cy * sin(x), k * sin(y) ]; } } function azimuthalInvert(angle) { return function(x, y) { var z = sqrt(x * x + y * y), c = angle(z), sc = sin(c), cc = cos(c); return [ atan2(x * sc, z * cc), asin(z && y * sc / z) ]; } } var azimuthalEqualAreaRaw = azimuthalRaw(function(cxcy) { return sqrt(2 / (1 + cxcy)); }); azimuthalEqualAreaRaw.invert = azimuthalInvert(function(z) { return 2 * asin(z / 2); }); function azimuthalEqualArea() { return projection(azimuthalEqualAreaRaw) .scale(124.75) .clipAngle(180 - 1e-3); } var azimuthalEquidistantRaw = azimuthalRaw(function(c) { return (c = acos(c)) && c / sin(c); }); azimuthalEquidistantRaw.invert = azimuthalInvert(function(z) { return z; }); function azimuthalEquidistant() { return projection(azimuthalEquidistantRaw) .scale(79.4188) .clipAngle(180 - 1e-3); } function mercatorRaw(lambda, phi) { return [lambda, log(tan((halfPi + phi) / 2))]; } mercatorRaw.invert = function(x, y) { return [x, 2 * atan(exp(y)) - halfPi]; }; function mercator() { return mercatorProjection(mercatorRaw) .scale(961 / tau); } function mercatorProjection(project) { var m = projection(project), center = m.center, scale = m.scale, translate = m.translate, clipExtent = m.clipExtent, x0 = null, y0, x1, y1; // clip extent m.scale = function(_) { return arguments.length ? (scale(_), reclip()) : scale(); }; m.translate = function(_) { return arguments.length ? (translate(_), reclip()) : translate(); }; m.center = function(_) { return arguments.length ? (center(_), reclip()) : center(); }; m.clipExtent = function(_) { return arguments.length ? ((_ == null ? x0 = y0 = x1 = y1 = null : (x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1])), reclip()) : x0 == null ? null : [[x0, y0], [x1, y1]]; }; function reclip() { var k = pi * scale(), t = m(rotation(m.rotate()).invert([0, 0])); return clipExtent(x0 == null ? [[t[0] - k, t[1] - k], [t[0] + k, t[1] + k]] : project === mercatorRaw ? [[Math.max(t[0] - k, x0), y0], [Math.min(t[0] + k, x1), y1]] : [[x0, Math.max(t[1] - k, y0)], [x1, Math.min(t[1] + k, y1)]]); } return reclip(); } function tany(y) { return tan((halfPi + y) / 2); } function conicConformalRaw(y0, y1) { var cy0 = cos(y0), n = y0 === y1 ? sin(y0) : log(cy0 / cos(y1)) / log(tany(y1) / tany(y0)), f = cy0 * pow(tany(y0), n) / n; if (!n) return mercatorRaw; function project(x, y) { if (f > 0) { if (y < -halfPi + epsilon) y = -halfPi + epsilon; } else { if (y > halfPi - epsilon) y = halfPi - epsilon; } var r = f / pow(tany(y), n); return [r * sin(n * x), f - r * cos(n * x)]; } project.invert = function(x, y) { var fy = f - y, r = sign(n) * sqrt(x * x + fy * fy), l = atan2(x, abs(fy)) * sign(fy); if (fy * n < 0) l -= pi * sign(x) * sign(fy); return [l / n, 2 * atan(pow(f / r, 1 / n)) - halfPi]; }; return project; } function conicConformal() { return conicProjection(conicConformalRaw) .scale(109.5) .parallels([30, 30]); } function equirectangularRaw(lambda, phi) { return [lambda, phi]; } equirectangularRaw.invert = equirectangularRaw; function equirectangular() { return projection(equirectangularRaw) .scale(152.63); } function conicEquidistantRaw(y0, y1) { var cy0 = cos(y0), n = y0 === y1 ? sin(y0) : (cy0 - cos(y1)) / (y1 - y0), g = cy0 / n + y0; if (abs(n) < epsilon) return equirectangularRaw; function project(x, y) { var gy = g - y, nx = n * x; return [gy * sin(nx), g - gy * cos(nx)]; } project.invert = function(x, y) { var gy = g - y, l = atan2(x, abs(gy)) * sign(gy); if (gy * n < 0) l -= pi * sign(x) * sign(gy); return [l / n, g - sign(n) * sqrt(x * x + gy * gy)]; }; return project; } function conicEquidistant() { return conicProjection(conicEquidistantRaw) .scale(131.154) .center([0, 13.9389]); } var A1 = 1.340264, A2 = -0.081106, A3 = 0.000893, A4 = 0.003796, M = sqrt(3) / 2, iterations = 12; function equalEarthRaw(lambda, phi) { var l = asin(M * sin(phi)), l2 = l * l, l6 = l2 * l2 * l2; return [ lambda * cos(l) / (M * (A1 + 3 * A2 * l2 + l6 * (7 * A3 + 9 * A4 * l2))), l * (A1 + A2 * l2 + l6 * (A3 + A4 * l2)) ]; } equalEarthRaw.invert = function(x, y) { var l = y, l2 = l * l, l6 = l2 * l2 * l2; for (var i = 0, delta, fy, fpy; i < iterations; ++i) { fy = l * (A1 + A2 * l2 + l6 * (A3 + A4 * l2)) - y; fpy = A1 + 3 * A2 * l2 + l6 * (7 * A3 + 9 * A4 * l2); l -= delta = fy / fpy, l2 = l * l, l6 = l2 * l2 * l2; if (abs(delta) < epsilon2) break; } return [ M * x * (A1 + 3 * A2 * l2 + l6 * (7 * A3 + 9 * A4 * l2)) / cos(l), asin(sin(l) / M) ]; }; function equalEarth() { return projection(equalEarthRaw) .scale(177.158); } function gnomonicRaw(x, y) { var cy = cos(y), k = cos(x) * cy; return [cy * sin(x) / k, sin(y) / k]; } gnomonicRaw.invert = azimuthalInvert(atan); function gnomonic() { return projection(gnomonicRaw) .scale(144.049) .clipAngle(60); } function identity() { var k = 1, tx = 0, ty = 0, sx = 1, sy = 1, // scale, translate and reflect alpha = 0, ca, sa, // angle x0 = null, y0, x1, y1, // clip extent kx = 1, ky = 1, transform = transformer({ point: function(x, y) { var p = projection([x, y]); this.stream.point(p[0], p[1]); } }), postclip = identity$1, cache, cacheStream; function reset() { kx = k * sx; ky = k * sy; cache = cacheStream = null; return projection; } function projection (p) { var x = p[0] * kx, y = p[1] * ky; if (alpha) { var t = y * ca - x * sa; x = x * ca + y * sa; y = t; } return [x + tx, y + ty]; } projection.invert = function(p) { var x = p[0] - tx, y = p[1] - ty; if (alpha) { var t = y * ca + x * sa; x = x * ca - y * sa; y = t; } return [x / kx, y / ky]; }; projection.stream = function(stream) { return cache && cacheStream === stream ? cache : cache = transform(postclip(cacheStream = stream)); }; projection.postclip = function(_) { return arguments.length ? (postclip = _, x0 = y0 = x1 = y1 = null, reset()) : postclip; }; projection.clipExtent = function(_) { return arguments.length ? (postclip = _ == null ? (x0 = y0 = x1 = y1 = null, identity$1) : clipRectangle(x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1]), reset()) : x0 == null ? null : [[x0, y0], [x1, y1]]; }; projection.scale = function(_) { return arguments.length ? (k = +_, reset()) : k; }; projection.translate = function(_) { return arguments.length ? (tx = +_[0], ty = +_[1], reset()) : [tx, ty]; }; projection.angle = function(_) { return arguments.length ? (alpha = _ % 360 * radians, sa = sin(alpha), ca = cos(alpha), reset()) : alpha * degrees; }; projection.reflectX = function(_) { return arguments.length ? (sx = _ ? -1 : 1, reset()) : sx < 0; }; projection.reflectY = function(_) { return arguments.length ? (sy = _ ? -1 : 1, reset()) : sy < 0; }; projection.fitExtent = function(extent, object) { return fitExtent(projection, extent, object); }; projection.fitSize = function(size, object) { return fitSize(projection, size, object); }; projection.fitWidth = function(width, object) { return fitWidth(projection, width, object); }; projection.fitHeight = function(height, object) { return fitHeight(projection, height, object); }; return projection; } function naturalEarth1Raw(lambda, phi) { var phi2 = phi * phi, phi4 = phi2 * phi2; return [ lambda * (0.8707 - 0.131979 * phi2 + phi4 * (-0.013791 + phi4 * (0.003971 * phi2 - 0.001529 * phi4))), phi * (1.007226 + phi2 * (0.015085 + phi4 * (-0.044475 + 0.028874 * phi2 - 0.005916 * phi4))) ]; } naturalEarth1Raw.invert = function(x, y) { var phi = y, i = 25, delta; do { var phi2 = phi * phi, phi4 = phi2 * phi2; phi -= delta = (phi * (1.007226 + phi2 * (0.015085 + phi4 * (-0.044475 + 0.028874 * phi2 - 0.005916 * phi4))) - y) / (1.007226 + phi2 * (0.015085 * 3 + phi4 * (-0.044475 * 7 + 0.028874 * 9 * phi2 - 0.005916 * 11 * phi4))); } while (abs(delta) > epsilon && --i > 0); return [ x / (0.8707 + (phi2 = phi * phi) * (-0.131979 + phi2 * (-0.013791 + phi2 * phi2 * phi2 * (0.003971 - 0.001529 * phi2)))), phi ]; }; function naturalEarth1() { return projection(naturalEarth1Raw) .scale(175.295); } function orthographicRaw(x, y) { return [cos(y) * sin(x), sin(y)]; } orthographicRaw.invert = azimuthalInvert(asin); function orthographic() { return projection(orthographicRaw) .scale(249.5) .clipAngle(90 + epsilon); } function stereographicRaw(x, y) { var cy = cos(y), k = 1 + cos(x) * cy; return [cy * sin(x) / k, sin(y) / k]; } stereographicRaw.invert = azimuthalInvert(function(z) { return 2 * atan(z); }); function stereographic() { return projection(stereographicRaw) .scale(250) .clipAngle(142); } function transverseMercatorRaw(lambda, phi) { return [log(tan((halfPi + phi) / 2)), -lambda]; } transverseMercatorRaw.invert = function(x, y) { return [-y, 2 * atan(exp(x)) - halfPi]; }; function transverseMercator() { var m = mercatorProjection(transverseMercatorRaw), center = m.center, rotate = m.rotate; m.center = function(_) { return arguments.length ? center([-_[1], _[0]]) : (_ = center(), [_[1], -_[0]]); }; m.rotate = function(_) { return arguments.length ? rotate([_[0], _[1], _.length > 2 ? _[2] + 90 : 90]) : (_ = rotate(), [_[0], _[1], _[2] - 90]); }; return rotate([0, 0, 90]) .scale(159.155); } exports.geoAlbers = albers; exports.geoAlbersUsa = albersUsa; exports.geoArea = area; exports.geoAzimuthalEqualArea = azimuthalEqualArea; exports.geoAzimuthalEqualAreaRaw = azimuthalEqualAreaRaw; exports.geoAzimuthalEquidistant = azimuthalEquidistant; exports.geoAzimuthalEquidistantRaw = azimuthalEquidistantRaw; exports.geoBounds = bounds; exports.geoCentroid = centroid; exports.geoCircle = circle; exports.geoClipAntimeridian = clipAntimeridian; exports.geoClipCircle = clipCircle; exports.geoClipExtent = extent; exports.geoClipRectangle = clipRectangle; exports.geoConicConformal = conicConformal; exports.geoConicConformalRaw = conicConformalRaw; exports.geoConicEqualArea = conicEqualArea; exports.geoConicEqualAreaRaw = conicEqualAreaRaw; exports.geoConicEquidistant = conicEquidistant; exports.geoConicEquidistantRaw = conicEquidistantRaw; exports.geoContains = contains; exports.geoDistance = distance; exports.geoEqualEarth = equalEarth; exports.geoEqualEarthRaw = equalEarthRaw; exports.geoEquirectangular = equirectangular; exports.geoEquirectangularRaw = equirectangularRaw; exports.geoGnomonic = gnomonic; exports.geoGnomonicRaw = gnomonicRaw; exports.geoGraticule = graticule; exports.geoGraticule10 = graticule10; exports.geoIdentity = identity; exports.geoInterpolate = interpolate; exports.geoLength = length; exports.geoMercator = mercator; exports.geoMercatorRaw = mercatorRaw; exports.geoNaturalEarth1 = naturalEarth1; exports.geoNaturalEarth1Raw = naturalEarth1Raw; exports.geoOrthographic = orthographic; exports.geoOrthographicRaw = orthographicRaw; exports.geoPath = index; exports.geoProjection = projection; exports.geoProjectionMutator = projectionMutator; exports.geoRotation = rotation; exports.geoStereographic = stereographic; exports.geoStereographicRaw = stereographicRaw; exports.geoStream = geoStream; exports.geoTransform = transform; exports.geoTransverseMercator = transverseMercator; exports.geoTransverseMercatorRaw = transverseMercatorRaw; }));