From fb9d95df0dbb840da87e4985f1ec2397dad575b1 Mon Sep 17 00:00:00 2001
From: Lawrence Thatcher <lwthatcher@msn.com>
Date: Mon, 12 Dec 2016 17:02:09 -0700
Subject: [PATCH] added findAll function to get all points within a radius

---
 src/findAll.js  | 69 +++++++++++++++++++++++++++++++++++++++++++++++++
 src/quadtree.js |  2 ++
 2 files changed, 71 insertions(+)
 create mode 100644 src/findAll.js

diff --git a/src/findAll.js b/src/findAll.js
new file mode 100644
index 0000000..1abadba
--- /dev/null
+++ b/src/findAll.js
@@ -0,0 +1,69 @@
+import Quad from "./quad";
+
+export default function(x, y, radius) {
+  var data,
+      x0 = this._x0,
+      y0 = this._y0,
+      x1,
+      y1,
+      x2,
+      y2,
+      x3 = this._x1,
+      y3 = this._y1,
+      quads = [],
+      node = this._root,
+      q,
+      i,
+      result = [];
+
+  if (node) quads.push(new Quad(node, x0, y0, x3, y3));
+  if (radius == null) radius = Infinity;
+  else {
+    x0 = x - radius, y0 = y - radius;
+    x3 = x + radius, y3 = y + radius;
+    radius *= radius;
+  }
+
+  while (q = quads.pop()) {
+
+    // Stop searching if this quadrant can’t contain a closer node.
+    if (!(node = q.node)
+        || (x1 = q.x0) > x3
+        || (y1 = q.y0) > y3
+        || (x2 = q.x1) < x0
+        || (y2 = q.y1) < y0) continue;
+
+    // Bisect the current quadrant.
+    if (node.length) {
+      var xm = (x1 + x2) / 2,
+          ym = (y1 + y2) / 2;
+
+      quads.push(
+        new Quad(node[3], xm, ym, x2, y2),
+        new Quad(node[2], x1, ym, xm, y2),
+        new Quad(node[1], xm, y1, x2, ym),
+        new Quad(node[0], x1, y1, xm, ym)
+      );
+
+      // Visit the closest quadrant first.
+      if (i = (y >= ym) << 1 | (x >= xm)) {
+        q = quads[quads.length - 1];
+        quads[quads.length - 1] = quads[quads.length - 1 - i];
+        quads[quads.length - 1 - i] = q;
+      }
+    }
+
+    // Visit this point. If within radius, add it.
+    else {
+      var dx = x - +this._x.call(null, node.data),
+          dy = y - +this._y.call(null, node.data),
+          d2 = dx * dx + dy * dy;
+      if (d2 < radius) {
+        // add all coincidence points as well
+        do result.push(node.data); while (node = node.next);
+      }
+    }
+  }
+
+  return result;
+}
diff --git a/src/quadtree.js b/src/quadtree.js
index faf2a6b..2bafac6 100644
--- a/src/quadtree.js
+++ b/src/quadtree.js
@@ -3,6 +3,7 @@ import tree_cover from "./cover";
 import tree_data from "./data";
 import tree_extent from "./extent";
 import tree_find from "./find";
+import tree_findAll from "./findAll";
 import tree_remove, {removeAll as tree_removeAll} from "./remove";
 import tree_root from "./root";
 import tree_size from "./size";
@@ -63,6 +64,7 @@ treeProto.cover = tree_cover;
 treeProto.data = tree_data;
 treeProto.extent = tree_extent;
 treeProto.find = tree_find;
+treeProto.findAll = tree_findAll;
 treeProto.remove = tree_remove;
 treeProto.removeAll = tree_removeAll;
 treeProto.root = tree_root;