rebrand

support converting from HilbertQuadkey to s2Cell.

README.md

@@ -1,6 +1,8 @@
 s2-geometry (JavaScript/ES5.1)
 ======================
 
+| Sponsored by [ppl](https://ppl.family)
+
 A pure JavaScript/ES5.1 port of Google/Niantic's S2 Geometry library (as used by **Ingress**, **Pokemon GO**)
 
 Currently contains basic support for S2Cell
@@ -118,6 +120,13 @@ var key = S2.idToKey(id);
 // '9749618446378729472'
 
 
+//
+// Convert between Quadkey and Id
+//
+var latlng = S2.keyToLatLng(key);
+var latlng = S2.idToLatLng(id);
+
+
 
 //
 // Neighbors
@@ -198,3 +207,12 @@ var hilbertQuadkey = S2.idToKey(cellId);
 
 console.log(hilbertQuadkey);
 ```
+
+Convert Key and Id to LatLng
+---------------------
+
+```javascript
+var latlng = S2.keyToLatLng('4/032212303102210');
+
+var latlng = S2.idToLatLng('9749618446378729472');
+```

bower.json

@@ -35,5 +35,5 @@
     "test",
     "tests"
   ],
-  "version": "1.2.8"
+  "version": "1.2.9"
 }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "s2-geometry",
-  "version": "1.2.8",
+  "version": "1.2.10",
   "description": "A pure JavaScript/ES5.1 port of Google/Niantic's S2 Geometry library (used by Ingress, Pokemon GO)",
   "main": "src/s2geometry.js",
   "scripts": {
@@ -8,7 +8,7 @@
   },
   "repository": {
     "type": "git",
-    "url": "git+https://github.com/Daplie/s2-geometry.js.git"
+    "url": "git+https://git.coolaj86.com/coolaj86/s2-geometry.js.git"
   },
   "keywords": [
     "s2",
@@ -27,12 +27,12 @@
     "lat",
     "lng"
   ],
-  "author": "AJ ONeal <aj@daplie.com> (https://coolaj86.com/)",
-  "license": "ISC",
+  "author": "AJ ONeal <coolaj86@gmail.com> (https://coolaj86.com/)",
+  "license": "(MIT or Apache-2 or ISC)",
   "bugs": {
-    "url": "https://github.com/Daplie/s2-geometry.js/issues"
+    "url": "https://git.coolaj86.com/coolaj86/s2-geometry.js/issues"
   },
-  "homepage": "https://github.com/Daplie/s2-geometry.js#readme",
+  "homepage": "https://git.coolaj86.com/coolaj86/s2-geometry.js#readme",
   "dependencies": {
     "long": "^3.2.0"
   }

src/s2geometry.js

@@ -200,6 +200,30 @@ S2.IJToST = function(ij,order,offsets) {
   ];
 };
 
+
+
+var rotateAndFlipQuadrant = function(n, point, rx, ry)
+{
+	var newX, newY;
+	if(ry == 0)
+	{
+		if(rx == 1){
+			point.x = n - 1 - point.x;
+			point.y = n - 1 - point.y
+
+		}
+
+    var x = point.x;
+		point.x = point.y
+		point.y = x;
+	}
+
+}
+
+
+
+
+
 // hilbert space-filling curve
 // based on http://blog.notdot.net/2009/11/Damn-Cool-Algorithms-Spatial-indexing-with-Quadtrees-and-Hilbert-Curves
 // note: rather then calculating the final integer hilbert position, we just return the list of quads
@@ -240,9 +264,59 @@ var pointToHilbertQuadList = function(x,y,order,face) {
 
 S2.S2Cell = function(){};
 
+S2.S2Cell.FromHilbertQuadKey = function(hilbertQuadkey) {
+  var parts = hilbertQuadkey.split('/');
+  var face = parseInt(parts[0]);
+  var position = parts[1];
+  var maxLevel = position.length;
+  var point = {
+    x : 0,
+    y: 0
+  };
+  var i;
+  var level;
+  var bit;
+  var rx, ry;
+  var val;
+
+	for(i = maxLevel - 1; i >= 0; i--) {
+
+		level = maxLevel - i;
+		bit = position[i];
+		rx = 0;
+    ry = 0;
+		if (bit === '1') {
+			ry = 1;
+		}
+		else if (bit === '2') {
+			rx = 1;
+			ry = 1;
+		}
+		else if (bit === '3') {
+			rx = 1;
+		}
+
+		val = Math.pow(2, level - 1);
+		rotateAndFlipQuadrant(val, point, rx, ry);
+
+		point.x += val * rx;
+		point.y += val * ry;
+
+	}
+
+  if (face % 2 === 1) {
+    var t = point.x;
+    point.x = point.y;
+    point.y = t;
+  }
+
+
+  return S2.S2Cell.FromFaceIJ(parseInt(face), [point.x, point.y], level);
+};
+
 //static method to construct
 S2.S2Cell.FromLatLng = function(latLng, level) {
-  if (!latLng.lat || !latLng.lng) {
+  if ((!latLng.lat && latLng.lat !== 0) || (!latLng.lng && latLng.lng !== 0)) {
     throw new Error("Pass { lat: lat, lng: lng } to S2.S2Cell.FromLatLng");
   }
   var xyz = S2.LatLngToXYZ(latLng);
@@ -254,6 +328,7 @@ S2.S2Cell.FromLatLng = function(latLng, level) {
 
   return S2.S2Cell.FromFaceIJ (faceuv[0], ij, level);
 };
+
 /*
 S2.faceIjLevelToXyz = function (face, ij, level) {
   var st = S2.IJToST(ij, level, [0.5, 0.5]);
@@ -444,8 +519,21 @@ S2.idToKey = S2.S2Cell.idToKey
   return faceS + '/' + posS;
 };
 
+S2.keyToLatLng = S2.S2Cell.keyToLatLng = function (key) {
+  var cell2 = S2.S2Cell.FromHilbertQuadKey(key);
+  return cell2.getLatLng();
+};
+
+S2.idToLatLng = S2.S2Cell.idToLatLng = function (id) {
+  var key = S2.idToKey(id);
+  return S2.keyToLatLng(key);
+};
+
 S2.S2Cell.latLngToKey = S2.latLngToKey
 = S2.latLngToQuadkey = function (lat, lng, level) {
+  if (isNaN(level) || level < 1 || level > 30) {
+    throw new Error("'level' is not a number between 1 and 30 (but it should be)");
+  }
   // TODO
   //
   // S2.idToLatLng(id)

tests/hilbert-to-cell.js

@@ -0,0 +1,36 @@
+'use strict';
+
+var S2 = require('../src/s2geometry.js').S2;
+
+for(var level = 1; level <= 20; level++) {
+	var success = 0;
+	var total = 0;
+	for (var x = -180.0; x < 180; x += 0.5) {
+		for (var y = -180.0; y < 180; y += 0.5) {
+
+				var latlng = { lat: x, lng: y };
+				var cell = S2.S2Cell.FromLatLng(latlng, level);
+				var quadKey = cell.toHilbertQuadkey();
+				var cell2 = S2.S2Cell.FromHilbertQuadKey(quadKey);
+
+				if(cell.face != cell2.face ||
+					cell.ij[0] != cell2.ij[0] ||
+					cell.ij[1] != cell2.ij[1] ||
+					cell.level != cell2.level)
+					{
+						/*console.log({
+							cell: cell,
+							cell2: cell2})*/
+
+					}
+					else
+					{
+						success++;
+					}
+					total++;
+				// check equal
+		}
+	}
+
+	console.log("level:" + level + "\t total:" + total + "\t success:" + success);
+}

tests/key-id-to-latlng.js

@@ -0,0 +1,48 @@
+'use strict';
+
+var S2 = require('../src/s2geometry.js').S2;
+var x, y;
+var count = 0;
+
+function refCheck() {
+  var refKey = '4/032212303102210';
+  var latlng = {
+    'lat': 40.2574448
+  , 'lng': -111.7089464
+  };
+
+  var key = S2.latLngToKey(latlng.lat, latlng.lng, 15);
+  if (key !== refKey) {
+    throw new Error("reference doesn't match");
+  }
+
+  var latlng1 = S2.keyToLatLng('4/032212303102210');
+  var key1 = S2.latLngToKey(latlng1.lat, latlng1.lng, 15);
+  if (key1 !== refKey) {
+    throw new Error("reference 1 doesn't match");
+  }
+
+  var latlng2 = S2.idToLatLng('9749618446378729472');
+  var key2 = S2.latLngToKey(latlng2.lat, latlng2.lng, 15);
+  if (key2 !== refKey) {
+    throw new Error("reference 2 doesn't match");
+  }
+}
+
+function checkReal(lat, lng) {
+  var key = S2.latLngToKey(lat, lng, 15);
+  var latlng = S2.keyToLatLng(key);
+  var key2 = S2.latLngToKey(latlng.lat, latlng.lng, 15);
+  if (key !== key2) {
+    throw new Error("keys do not match", latlng, key, key2);
+  }
+}
+
+for (x = -180; x <= 180; x += (0 + Math.random())) {
+  for (y = -180; y <= 180; y += (0 + Math.random())) {
+    count += 1;
+    checkReal(x, y);
+  }
+}
+
+console.log('PASS:', count, 'random locations without any key mismatches');