Index: node_modules/d3-zoom/src/transform.js
===================================================================
--- node_modules/d3-zoom/src/transform.js	(revision e4c61dd6cd86e06265bc2bd91adba84a0f04044a)
+++ node_modules/d3-zoom/src/transform.js	(revision e4c61dd6cd86e06265bc2bd91adba84a0f04044a)
@@ -0,0 +1,51 @@
+export function Transform(k, x, y) {
+  this.k = k;
+  this.x = x;
+  this.y = y;
+}
+
+Transform.prototype = {
+  constructor: Transform,
+  scale: function(k) {
+    return k === 1 ? this : new Transform(this.k * k, this.x, this.y);
+  },
+  translate: function(x, y) {
+    return x === 0 & y === 0 ? this : new Transform(this.k, this.x + this.k * x, this.y + this.k * y);
+  },
+  apply: function(point) {
+    return [point[0] * this.k + this.x, point[1] * this.k + this.y];
+  },
+  applyX: function(x) {
+    return x * this.k + this.x;
+  },
+  applyY: function(y) {
+    return y * this.k + this.y;
+  },
+  invert: function(location) {
+    return [(location[0] - this.x) / this.k, (location[1] - this.y) / this.k];
+  },
+  invertX: function(x) {
+    return (x - this.x) / this.k;
+  },
+  invertY: function(y) {
+    return (y - this.y) / this.k;
+  },
+  rescaleX: function(x) {
+    return x.copy().domain(x.range().map(this.invertX, this).map(x.invert, x));
+  },
+  rescaleY: function(y) {
+    return y.copy().domain(y.range().map(this.invertY, this).map(y.invert, y));
+  },
+  toString: function() {
+    return "translate(" + this.x + "," + this.y + ") scale(" + this.k + ")";
+  }
+};
+
+export var identity = new Transform(1, 0, 0);
+
+transform.prototype = Transform.prototype;
+
+export default function transform(node) {
+  while (!node.__zoom) if (!(node = node.parentNode)) return identity;
+  return node.__zoom;
+}