From 15dda93e3b0ce91fd294a09b0a194b07403a9fff Mon Sep 17 00:00:00 2001
From: Jason Davies <jason@jasondavies.com>
Date: Mon, 12 Sep 2011 17:23:32 +0100
Subject: [PATCH] Reinstate d3.geo.greatCircle.polyline.

For backwards compatibility.
---
 d3.geo.js                         | 52 +++++++++++++++----------------
 d3.geo.min.js                     |  2 +-
 examples/azimuthal/azimuthal.html |  2 +-
 examples/azimuthal/azimuthal.js   |  2 +-
 src/geo/clip.js                   |  4 +--
 src/geo/greatCircle.js            | 48 ++++++++++++++--------------
 test/geo/greatCircle-test.js      | 12 +++----
 7 files changed, 61 insertions(+), 61 deletions(-)

diff --git a/d3.geo.js b/d3.geo.js
index 5cb4b3bbfb839..e03cc67467e44 100644
--- a/d3.geo.js
+++ b/d3.geo.js
@@ -622,15 +622,22 @@ function d3_geo_boundsPolygon(o, f) {
 }
 // From http://williams.best.vwh.net/avform.htm#Intermediate
 d3.geo.greatCircle = function() {
-  var coordinates = Object,
+  var source = d3_geo_greatCircleSource,
+      target = d3_geo_greatCircleTarget,
+      coordinates = Object, // for use with polyline
       precision = 1,
       radius = d3_geo_earthRadius;
   // TODO: breakAtDateLine?
 
   function greatCircle(d, i) {
-    return d3_geo_greatCirclePath(coordinates.call(this, d, i), precision);
+    return d3_geo_greatCirclePath([
+      source.call(this, d, i), target.call(this, d, i)], precision);
   }
 
+  greatCircle.polyline = function(d, i) {
+    return d3_geo_greatCirclePath(coordinates.call(this, d, i), precision);
+  };
+
   greatCircle.coordinates = function(x) {
     if (!arguments.length) return coordinates;
     coordinates = x;
@@ -651,29 +658,16 @@ d3.geo.greatCircle = function() {
 
   // Haversine formula for great-circle distance.
   greatCircle.distance = function(d, i) {
-    d = coordinates.call(this, d, i);
-    if (d.length < 2) return NaN;
-
-    var from = d[0],
-        to,
+    var from = source.call(this, d, i),
+        to = target.call(this, d, i),
         x0 = from[0] * d3_radians,
         y0 = from[1] * d3_radians,
-        n = d.length,
-        i = 0,
-        s = 0;
-
-    while (++i < n) {
-      to = d[i];
-      var x1 = to[0] * d3_radians,
-          y1 = to[1] * d3_radians,
-          sy = Math.sin((y1 - y0) / 2),
-          sx = Math.sin((x1 - x0) / 2),
-          a = sy * sy + Math.cos(y0) * Math.cos(y1) * sx * sx;
-      x0 = x1;
-      y0 = y1;
-      s += radius * 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
-    }
-    return s;
+        x1 = to[0] * d3_radians,
+        y1 = to[1] * d3_radians,
+        sy = Math.sin((y1 - y0) / 2),
+        sx = Math.sin((x1 - x0) / 2),
+        a = sy * sy + Math.cos(y0) * Math.cos(y1) * sx * sx;
+    return radius * 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
   };
 
   return greatCircle;
@@ -727,6 +721,14 @@ function d3_geo_greatCirclePath(coordinates, precision) {
 
   return path;
 }
+
+function d3_geo_greatCircleSource(d) {
+  return d.source;
+}
+
+function d3_geo_greatCircleTarget(d) {
+  return d.target;
+}
 d3.geo.clip = function() {
   var origin = [0, 0],
       angle = 90,
@@ -790,9 +792,7 @@ d3.geo.clip = function() {
   return clip;
 }
 
-var d3_geo_clipGreatCircle = d3.geo.greatCircle().coordinates(function(d) {
-  return [d.source, d.target];
-});
+var d3_geo_clipGreatCircle = d3.geo.greatCircle();
 
 function d3_geo_clipIntersect(from, to, f) {
   var x0 = from[0] * d3_radians,
diff --git a/d3.geo.min.js b/d3.geo.min.js
index 2b9062607f867..17aa763d926ca 100644
--- a/d3.geo.min.js
+++ b/d3.geo.min.js
@@ -1 +1 @@
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B=Math.sin(v-z)/w,C=Math.sin(z)/w,D=B*m*k+C*t*r,E=B*m*l+C*t*s,F=B*n+C*u;o.push([Math.atan2(E,D)/a,Math.atan2(F,Math.sqrt(D*D+E*E))/a])}o.push(h),i=p,j=q,k=r,l=s,m=t,n=u}return o}function n(a,b){for(var c=a.coordinates[0],d=0,e=c.length;d<e;d++)b.apply(null,c[d])}function m(a,b){b.apply(null,a.coordinates)}function l(a,b){for(var c=a.coordinates,d=0,e=c.length;d<e;d++)for(var f=c[d][0],g=0,h=f.length;g<h;g++)b.apply(null,f[g])}function k(a,b){for(var c=a.coordinates,d=0,e=c.length;d<e;d++)for(var f=c[d],g=0,h=f.length;g<h;g++)b.apply(null,f[g])}function j(a,b){for(var c=a.coordinates,d=0,e=c.length;d<e;d++)b.apply(null,c[d])}function i(a,b){for(var c=a.features,d=0,e=c.length;d<e;d++)f(c[d].geometry,b)}function h(a,b){f(a.geometry,b)}function f(a,b){a.type in g&&g[a.type](a,b)}function e(a,b){return b&&b.type in a?a[b.type](b):""}function d(){return 0}function c(a){return"m0,"+a+"a"+a+","+a+" 0 1,1 0,"+ -2*a+"a"+a+","+a+" 0 1,1 0,"+2*a+"z"}d3.geo={};var a=Math.PI/180,b=6371;d3.geo.azimuthal=function(){function j(c){var g=c[0]*a-f,j=c[1]*a,k=Math.cos(g),l=Math.sin(g),m=Math.cos(j),n=Math.sin(j),o=b!=="orthographic"?i*n+h*m*k:null,p,q=b==="stereographic"?1/(1+o):b==="gnomonic"?1/o:b==="equidistant"?(p=Math.acos(o),p?p/Math.sin(p):0):b==="equalarea"?Math.sqrt(2/(1+o)):1,r=q*m*l,s=q*(i*m*k-h*n);return[d*r+e[0],d*s+e[1]]}var b="orthographic",c,d=200,e=[480,250],f,g,h,i;j.invert=function(c){var g=(c[0]-e[0])/d,j=(c[1]-e[1])/d,k=Math.sqrt(g*g+j*j),l=b==="stereographic"?2*Math.atan(k):b==="gnomonic"?Math.atan(k):b==="equidistant"?k:b==="equalarea"?2*Math.asin(.5*k):Math.asin(k),m=Math.sin(l),n=Math.cos(l);return[(f+Math.atan2(g*m,k*h*n+j*i*m))/a,Math.asin(n*i-(k?j*m*h/k:0))/a]},j.mode=function(a){if(!arguments.length)return b;b=a+"";return j},j.origin=function(b){if(!arguments.length)return c;c=b,f=c[0]*a,g=c[1]*a,h=Math.cos(g),i=Math.sin(g);return j},j.scale=function(a){if(!arguments.length)return d;d=+a;return j},j.translate=function(a){if(!arguments.length)return e;e=[+a[0],+a[1]];return j};return j.origin([0,0])},d3.geo.albers=function(){function k(){var d=a*c[0],e=a*c[1],k=a*b[1],l=Math.sin(d),m=Math.cos(d);f=a*b[0],g=.5*(l+Math.sin(e)),h=m*m+2*g*l,i=Math.sqrt(h-2*g*Math.sin(k))/g;return j}function j(b){var c=g*(a*b[0]-f),j=Math.sqrt(h-2*g*Math.sin(a*b[1]))/g;return[d*j*Math.sin(c)+e[0],d*(j*Math.cos(c)-i)+e[1]]}var b=[-98,38],c=[29.5,45.5],d=1e3,e=[480,250],f,g,h,i;j.invert=function(b){var c=(b[0]-e[0])/d,j=(b[1]-e[1])/d,k=i+j,l=Math.atan2(c,k),m=Math.sqrt(c*c+k*k);return[(f+l/g)/a,Math.asin((h-m*m*g*g)/(2*g))/a]},j.origin=function(a){if(!arguments.length)return b;b=[+a[0],+a[1]];return k()},j.parallels=function(a){if(!arguments.length)return c;c=[+a[0],+a[1]];return k()},j.scale=function(a){if(!arguments.length)return d;d=+a;return j},j.translate=function(a){if(!arguments.length)return e;e=[+a[0],+a[1]];return j};return k()},d3.geo.albersUsa=function(){function e(e){var f=e[0],g=e[1];return(g>50?b:f<-140?c:g<21?d:a)(e)}var a=d3.geo.albers(),b=d3.geo.albers().origin([-160,60]).parallels([55,65]),c=d3.geo.albers().origin([-160,20]).parallels([8,18]),d=d3.geo.albers().origin([-60,10]).parallels([8,18]);e.scale=function(f){if(!arguments.length)return a.scale();a.scale(f),b.scale(f*.6),c.scale(f),d.scale(f*1.5);return e.translate(a.translate())},e.translate=function(f){if(!arguments.length)return a.translate();var g=a.scale()/1e3,h=f[0],i=f[1];a.translate(f),b.translate([h-400*g,i+170*g]),c.translate([h-190*g,i+200*g]),d.translate([h+580*g,i+430*g]);return e};return e.scale(a.scale())},d3.geo.mercator=function(){function d(d){var e=d[0]/360,f=-(Math.log(Math.tan(Math.PI/4+d[1]*a/2))/a)/360;return[b*e+c[0],b*Math.max(-0.5,Math.min(.5,f))+c[1]]}var b=500,c=[480,250];d.invert=function(d){var e=(d[0]-c[0])/b,f=(d[1]-c[1])/b;return[360*e,2*Math.atan(Math.exp(-360*f*a))/a-90]},d.scale=function(a){if(!arguments.length)return b;b=+a;return d},d.translate=function(a){if(!arguments.length)return c;c=[+a[0],+a[1]];return d};return d},d3.geo.path=function(){function o(a){return Math.abs(d3.geom.polygon(a.map(f)).area())}function m(a){var b=d3.geom.polygon(a[0].map(f)),c=b.centroid(1),d=c[0],e=c[1],g=Math.abs(b.area()),h=0,i=a.length;while(++h<i)b=d3.geom.polygon(a[h].map(f)),c=b.centroid(1),d-=c[0],e-=c[1],g-=Math.abs(b.area());return[d,e,6*g]}function l(a){var b=o(a[0]),c=0,d=a.length;while(++c<d)b-=o(a[c]);return b}function i(a){return f(a).join(",")}function h(d,f){typeof a=="function"&&(b=c(a.apply(this,arguments)));return e(j,d)}var a=4.5,b=c(a),f=d3.geo.albersUsa(),g=Object,j={FeatureCollection:function(a){var b=[],c=a.features,d=-1,f=c.length;while(++d<f)b.push(e(j,c[d].geometry));return b.join("")},Feature:function(a){return e(j,a.geometry)},Point:function(a){var c=g.call(this,[a.coordinates]);return c.length?"M"+i(c[0])+b:""},MultiPoint:function(a){var c=[],d=g.call(this,a.coordinates),e=-1,f=d.length;while(++e<f)c.push("M",i(d[e]),b);return c.join("")},LineString:function(a){var b=["M"],c=g.call(this,a.coordinates),d=-1,e=c.length;while(++d<e)b.push(i(c[d]),"L");b.pop();return b.join("")},MultiLineString:function(a){var b=[],c=a.coordinates,d=-1,e=c.length,f,h,j;while(++d<e){f=g.call(this,c[d]),h=-1,j=f.length,b.push("M");while(++h<j)b.push(i(f[h]),"L");b.pop()}return b.join("")},Polygon:function(a){var b=[],c=a.coordinates,d=-1,e=c.length,f,h,j;while(++d<e){f=g.call(this,c[d]),h=-1,j=f.length-1;if(j<1)continue;b.push("M");while(++h<j)b.push(i(f[h]),"L");b[b.length-1]="Z"}return b.join("")},MultiPolygon:function(a){var b=[],c=a.coordinates,d=-1,e=c.length,f,h,j,k,l,m;while(++d<e){f=c[d],h=-1,j=f.length;while(++h<j){k=g.call(this,f[h]),l=-1,m=k.length-1;if(m<1)continue;b.push("M");while(++l<m)b.push(i(k[l]),"L");b[b.length-1]="Z"}}return b.join("")},GeometryCollection:function(a){var b=[],c=a.geometries,d=-1,f=c.length;while(++d<f)b.push(e(j,c[d]));return b.join("")}},k={FeatureCollection:function(a){var b=0,c=a.features,d=-1,f=c.length;while(++d<f)b+=e(k,c[d]);return b},Feature:function(a){return e(k,a.geometry)},Point:d,MultiPoint:d,LineString:d,MultiLineString:d,Polygon:function(a){return l(a.coordinates)},MultiPolygon:function(a){var b=0,c=a.coordinates,d=-1,e=c.length;while(++d<e)b+=l(c[d]);return b},GeometryCollection:function(a){var b=0,c=a.geometries,d=-1,f=c.length;while(++d<f)b+=e(k,c[d]);return b}},n={Feature:function(a){return e(n,a.geometry)},Polygon:function(a){var b=m(a.coordinates);return[b[0]/b[2],b[1]/b[2]]},MultiPolygon:function(a){var b=0,c=a.coordinates,d,e=0,f=0,g=0,h=-1,i=c.length;while(++h<i)d=m(c[h]),e+=d[0],f+=d[1],g+=d[2];return[e/g,f/g]}};h.projection=function(a){f=a;return h},h.clip=function(a){if(!arguments.length)return g;g=a;return h},h.area=function(a){return e(k,a)},h.centroid=function(a){return e(n,a)},h.pointRadius=function(d){typeof d=="function"?a=d:(a=+d,b=c(a));return h};return h},d3.geo.bounds=function(a){var b=Infinity,c=Infinity,d=-Infinity,e=-Infinity;f(a,function(a,f){a<b&&(b=a),a>d&&(d=a),f<c&&(c=f),f>e&&(e=f)});return[[b,c],[d,e]]};var g={Feature:h,FeatureCollection:i,LineString:j,MultiLineString:k,MultiPoint:j,MultiPolygon:l,Point:m,Polygon:n};d3.geo.greatCircle=function(){function h(a,b){return o([c.call(this,a,b),d.call(this,a,b)],f)}var c=p,d=q,e=Object,f=1,g=b;h.polyline=function(a,b){return o(e.call(this,a,b),f)},h.coordinates=function(a){if(!arguments.length)return e;e=a;return h},h.precision=function(a){if(!arguments.length)return f;f=+a;return h},h.radius=function(a){if(!arguments.length)return g;g=+a;return h},h.distance=function(b,e){var f=c.call(this,b,e),h=d.call(this,b,e),i=f[0]*a,j=f[1]*a,k=h[0]*a,l=h[1]*a,m=Math.sin((l-j)/2),n=Math.sin((k-i)/2),o=m*m+Math.cos(j)*Math.cos(l)*n*n;return g*2*Math.atan2(Math.sqrt(o),Math.sqrt(1-o))};return h},d3.geo.clip=function(){function f(b,c){var b=e.call(this,b,c),f={source:a,target:null},g=b.length,c=-1,h,i=[],j=null,k=null,l,m;while(++c<g)f.target=b[c],l=r.distance(f),l<d?(k&&i.push(s(k,f.target,(m-d)/(m-l))),i.push(b[c]),j=k=null):(k=f.target,!j&&i.length&&(i.push(s(i[i.length-1],k,(d-m)/(l-m))),j=k)),m=l;k&&i.length&&(f.target=i[0],l=r.distance(f),i.push(s(k,f.target,(m-d)/(m-l))));return i}var a=[0,0],c=90,d=b*c/180*Math.PI,e=Object;f.coordinates=function(a){if(!arguments.length)return e;e=a;return f},f.origin=function(b){if(!arguments.length)return a;a=b;return f},f.angle=function(a){if(!arguments.length)return c;c=+a,d=b*c/180*Math.PI;return f};return f};var r=d3.geo.greatCircle()})()
\ No newline at end of file
diff --git a/examples/azimuthal/azimuthal.html b/examples/azimuthal/azimuthal.html
index bb8b963ff8cb3..195aea1af1443 100644
--- a/examples/azimuthal/azimuthal.html
+++ b/examples/azimuthal/azimuthal.html
@@ -91,7 +91,7 @@ <h3>Azimuthal Projection</h3>
 $("#mode").change(function() {
   var mode = $(this).val();
   xy.mode(mode);
-  path.clip(mode === "gnomonic" ? clip : circle);
+  path.clip(mode === "gnomonic" ? clip : circle.polyline);
   refresh(500);
 });
 
diff --git a/examples/azimuthal/azimuthal.js b/examples/azimuthal/azimuthal.js
index 0221983eff873..b8013749284a2 100644
--- a/examples/azimuthal/azimuthal.js
+++ b/examples/azimuthal/azimuthal.js
@@ -1,7 +1,7 @@
 var xy = d3.geo.azimuthal().scale(240).mode("stereographic"),
     clip = d3.geo.clip().angle(89),
     circle = d3.geo.greatCircle().precision(10).coordinates(clip),
-    path = d3.geo.path().projection(xy).clip(circle),
+    path = d3.geo.path().projection(xy).clip(circle.polyline),
     svg = d3.select("body").append("svg:svg");
 
 d3.json("../data/world-countries.json", function(collection) {
diff --git a/src/geo/clip.js b/src/geo/clip.js
index dc932bbcc31c7..a2f96e7a65769 100644
--- a/src/geo/clip.js
+++ b/src/geo/clip.js
@@ -61,9 +61,7 @@ d3.geo.clip = function() {
   return clip;
 }
 
-var d3_geo_clipGreatCircle = d3.geo.greatCircle().coordinates(function(d) {
-  return [d.source, d.target];
-});
+var d3_geo_clipGreatCircle = d3.geo.greatCircle();
 
 function d3_geo_clipIntersect(from, to, f) {
   var x0 = from[0] * d3_radians,
diff --git a/src/geo/greatCircle.js b/src/geo/greatCircle.js
index 2423de91aefc1..4c5dffbd1bd6a 100644
--- a/src/geo/greatCircle.js
+++ b/src/geo/greatCircle.js
@@ -1,14 +1,21 @@
 // From http://williams.best.vwh.net/avform.htm#Intermediate
 d3.geo.greatCircle = function() {
-  var coordinates = Object,
+  var source = d3_geo_greatCircleSource,
+      target = d3_geo_greatCircleTarget,
+      coordinates = Object, // for use with polyline
       precision = 1,
       radius = d3_geo_earthRadius;
   // TODO: breakAtDateLine?
 
   function greatCircle(d, i) {
-    return d3_geo_greatCirclePath(coordinates.call(this, d, i), precision);
+    return d3_geo_greatCirclePath([
+      source.call(this, d, i), target.call(this, d, i)], precision);
   }
 
+  greatCircle.polyline = function(d, i) {
+    return d3_geo_greatCirclePath(coordinates.call(this, d, i), precision);
+  };
+
   greatCircle.coordinates = function(x) {
     if (!arguments.length) return coordinates;
     coordinates = x;
@@ -29,29 +36,16 @@ d3.geo.greatCircle = function() {
 
   // Haversine formula for great-circle distance.
   greatCircle.distance = function(d, i) {
-    d = coordinates.call(this, d, i);
-    if (d.length < 2) return NaN;
-
-    var from = d[0],
-        to,
+    var from = source.call(this, d, i),
+        to = target.call(this, d, i),
         x0 = from[0] * d3_radians,
         y0 = from[1] * d3_radians,
-        n = d.length,
-        i = 0,
-        s = 0;
-
-    while (++i < n) {
-      to = d[i];
-      var x1 = to[0] * d3_radians,
-          y1 = to[1] * d3_radians,
-          sy = Math.sin((y1 - y0) / 2),
-          sx = Math.sin((x1 - x0) / 2),
-          a = sy * sy + Math.cos(y0) * Math.cos(y1) * sx * sx;
-      x0 = x1;
-      y0 = y1;
-      s += radius * 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
-    }
-    return s;
+        x1 = to[0] * d3_radians,
+        y1 = to[1] * d3_radians,
+        sy = Math.sin((y1 - y0) / 2),
+        sx = Math.sin((x1 - x0) / 2),
+        a = sy * sy + Math.cos(y0) * Math.cos(y1) * sx * sx;
+    return radius * 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
   };
 
   return greatCircle;
@@ -105,3 +99,11 @@ function d3_geo_greatCirclePath(coordinates, precision) {
 
   return path;
 }
+
+function d3_geo_greatCircleSource(d) {
+  return d.source;
+}
+
+function d3_geo_greatCircleTarget(d) {
+  return d.target;
+}
diff --git a/test/geo/greatCircle-test.js b/test/geo/greatCircle-test.js
index 9c0b084cb90ac..24c41f085bc55 100644
--- a/test/geo/greatCircle-test.js
+++ b/test/geo/greatCircle-test.js
@@ -13,14 +13,14 @@ suite.addBatch({
       return d3.geo.greatCircle().precision(7.5);
     },
     "distance": function(circle) {
-      assert.equal(circle.distance([[0, 0], [0, 0]]), 0);
-      assert.inDelta(circle.distance([
-        [118 + 24 / 60, 33 + 57 / 60],
-        [ 73 + 47 / 60, 40 + 38 / 60]
-      ]), 3973, .5);
+      assert.equal(circle.distance({source: [0, 0], target: [0, 0]}), 0);
+      assert.inDelta(circle.distance({
+        source: [118 + 24 / 60, 33 + 57 / 60],
+        target: [ 73 + 47 / 60, 40 + 38 / 60]
+      }), 3973, .5);
     },
     "geodesic": function(circle) {
-      assert.inDelta(circle([[5, 52], [-120, 37]]), [
+      assert.inDelta(circle.polyline([[5, 52], [-120, 37]]), [
         [   5,        52      ],
         [  -3.805036, 57.05083],
         [ -15.122869, 61.30118],