diff --git a/src/s2geometry.js b/src/s2geometry.js
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+++ b/src/s2geometry.js
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+/// S2 Geometry functions
+// the regional scoreboard is based on a level 6 S2 Cell
+// - https://docs.google.com/presentation/d/1Hl4KapfAENAOf4gv-pSngKwvS_jwNVHRPZTTDzXXn6Q/view?pli=1#slide=id.i22
+// at the time of writing there's no actual API for the intel map to retrieve scoreboard data,
+// but it's still useful to plot the score cells on the intel map
+
+
+// the S2 geometry is based on projecting the earth sphere onto a cube, with some scaling of face coordinates to
+// keep things close to approximate equal area for adjacent cells
+// to convert a lat,lng into a cell id:
+// - convert lat,lng to x,y,z
+// - convert x,y,z into face,u,v
+// - u,v scaled to s,t with quadratic formula
+// - s,t converted to integer i,j offsets
+// - i,j converted to a position along a Hubbert space-filling curve
+// - combine face,position to get the cell id
+
+//NOTE: compared to the google S2 geometry library, we vary from their code in the following ways
+// - cell IDs: they combine face and the hilbert curve position into a single 64 bit number. this gives efficient space
+//             and speed. javascript doesn't have appropriate data types, and speed is not cricical, so we use
+//             as [face,[bitpair,bitpair,...]] instead
+// - i,j: they always use 30 bits, adjusting as needed. we use 0 to (1<<level)-1 instead
+//        (so GetSizeIJ for a cell is always 1)
+
+(function() {
+
+window.S2 = {};
+
+
+var LatLngToXYZ = function(latLng) {
+  var d2r = L.LatLng.DEG_TO_RAD;
+
+  var phi = latLng.lat*d2r;
+  var theta = latLng.lng*d2r;
+
+  var cosphi = Math.cos(phi);
+
+  return [Math.cos(theta)*cosphi, Math.sin(theta)*cosphi, Math.sin(phi)];
+};
+
+var XYZToLatLng = function(xyz) {
+  var r2d = L.LatLng.RAD_TO_DEG;
+
+  var lat = Math.atan2(xyz[2], Math.sqrt(xyz[0]*xyz[0]+xyz[1]*xyz[1]));
+  var lng = Math.atan2(xyz[1], xyz[0]);
+
+  return L.latLng(lat*r2d, lng*r2d);
+};
+
+var largestAbsComponent = function(xyz) {
+  var temp = [Math.abs(xyz[0]), Math.abs(xyz[1]), Math.abs(xyz[2])];
+
+  if (temp[0] > temp[1]) {
+    if (temp[0] > temp[2]) {
+      return 0;
+    } else {
+      return 2;
+    }
+  } else {
+    if (temp[1] > temp[2]) {
+      return 1;
+    } else {
+      return 2;
+    }
+  }
+
+};
+
+var faceXYZToUV = function(face,xyz) {
+  var u,v;
+
+  switch (face) {
+    case 0: u =  xyz[1]/xyz[0]; v =  xyz[2]/xyz[0]; break;
+    case 1: u = -xyz[0]/xyz[1]; v =  xyz[2]/xyz[1]; break;
+    case 2: u = -xyz[0]/xyz[2]; v = -xyz[1]/xyz[2]; break;
+    case 3: u =  xyz[2]/xyz[0]; v =  xyz[1]/xyz[0]; break;
+    case 4: u =  xyz[2]/xyz[1]; v = -xyz[0]/xyz[1]; break;
+    case 5: u = -xyz[1]/xyz[2]; v = -xyz[0]/xyz[2]; break;
+    default: throw {error: 'Invalid face'}; break;
+  }
+
+  return [u,v];
+}
+
+
+
+
+var XYZToFaceUV = function(xyz) {
+  var face = largestAbsComponent(xyz);
+
+  if (xyz[face] < 0) {
+    face += 3;
+  }
+
+  uv = faceXYZToUV (face,xyz);
+
+  return [face, uv];
+};
+
+var FaceUVToXYZ = function(face,uv) {
+  var u = uv[0];
+  var v = uv[1];
+
+  switch (face) {
+    case 0: return [ 1, u, v];
+    case 1: return [-u, 1, v];
+    case 2: return [-u,-v, 1];
+    case 3: return [-1,-v,-u];
+    case 4: return [ v,-1,-u];
+    case 5: return [ v, u,-1];
+    default: throw {error: 'Invalid face'};
+  }
+};
+
+
+var STToUV = function(st) {
+  var singleSTtoUV = function(st) {
+    if (st >= 0.5) {
+      return (1/3.0) * (4*st*st - 1);
+    } else {
+      return (1/3.0) * (1 - (4*(1-st)*(1-st)));
+    }
+  }
+
+  return [singleSTtoUV(st[0]), singleSTtoUV(st[1])];
+};
+
+
+
+var UVToST = function(uv) {
+  var singleUVtoST = function(uv) {
+    if (uv >= 0) {
+      return 0.5 * Math.sqrt (1 + 3*uv);
+    } else {
+      return 1 - 0.5 * Math.sqrt (1 - 3*uv);
+    }
+  }
+
+  return [singleUVtoST(uv[0]), singleUVtoST(uv[1])];
+};
+
+
+var STToIJ = function(st,order) {
+  var maxSize = (1<<order);
+
+  var singleSTtoIJ = function(st) {
+    var ij = Math.floor(st * maxSize);
+    return Math.max(0, Math.min(maxSize-1, ij));
+  };
+
+  return [singleSTtoIJ(st[0]), singleSTtoIJ(st[1])];
+};
+
+
+var IJToST = function(ij,order,offsets) {
+  var maxSize = (1<<order);
+
+  return [
+    (ij[0]+offsets[0])/maxSize,
+    (ij[1]+offsets[1])/maxSize
+  ];
+}
+
+// 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
+// this ensures no precision issues whth large orders (S3 cell IDs use up to 30), and is more
+// convenient for pulling out the individual bits as needed later
+var pointToHilbertQuadList = function(x,y,order) {
+  var hilbertMap = {
+    'a': [ [0,'d'], [1,'a'], [3,'b'], [2,'a'] ],
+    'b': [ [2,'b'], [1,'b'], [3,'a'], [0,'c'] ],
+    'c': [ [2,'c'], [3,'d'], [1,'c'], [0,'b'] ],
+    'd': [ [0,'a'], [3,'c'], [1,'d'], [2,'d'] ]  
+  };
+
+  var currentSquare='a';
+  var positions = [];
+
+  for (var i=order-1; i>=0; i--) {
+
+    var mask = 1<<i;
+
+    var quad_x = x&mask ? 1 : 0;
+    var quad_y = y&mask ? 1 : 0;
+
+    var t = hilbertMap[currentSquare][quad_x*2+quad_y];
+
+    positions.push(t[0]);
+
+    currentSquare = t[1];
+  }
+
+  return positions;
+};
+
+
+
+
+// S2Cell class
+
+S2.S2Cell = function(){};
+
+//static method to construct
+S2.S2Cell.FromLatLng = function(latLng,level) {
+
+  var xyz = LatLngToXYZ(latLng);
+
+  var faceuv = XYZToFaceUV(xyz);
+  var st = UVToST(faceuv[1]);
+
+  var ij = STToIJ(st,level);
+
+  return S2.S2Cell.FromFaceIJ (faceuv[0], ij, level);
+
+  return result;
+};
+
+S2.S2Cell.FromFaceIJ = function(face,ij,level) {
+  var cell = new S2.S2Cell();
+  cell.face = face;
+  cell.ij = ij;
+  cell.level = level;
+
+  return cell;
+};
+
+
+S2.S2Cell.prototype.toString = function() {
+  return 'F'+this.face+'ij['+this.ij[0]+','+this.ij[1]+']@'+this.level;
+};
+
+S2.S2Cell.prototype.getLatLng = function() {
+  var st = IJToST(this.ij,this.level, [0.5,0.5]);
+  var uv = STToUV(st);
+  var xyz = FaceUVToXYZ(this.face, uv);
+
+  return XYZToLatLng(xyz);  
+};
+
+S2.S2Cell.prototype.getCornerLatLngs = function() {
+  var result = [];
+  var offsets = [
+    [ 0.0, 0.0 ],
+    [ 0.0, 1.0 ],
+    [ 1.0, 1.0 ],
+    [ 1.0, 0.0 ]
+  ];
+
+  for (var i=0; i<4; i++) {
+    var st = IJToST(this.ij, this.level, offsets[i]);
+    var uv = STToUV(st);
+    var xyz = FaceUVToXYZ(this.face, uv);
+
+    result.push ( XYZToLatLng(xyz) );
+  }
+  return result;
+};
+
+
+S2.S2Cell.prototype.getFaceAndQuads = function() {
+  var quads = pointToHilbertQuadList(this.ij[0], this.ij[1], this.level);
+
+  return [this.face,quads];
+};
+
+S2.S2Cell.prototype.getNeighbors = function() {
+
+  var fromFaceIJWrap = function(face,ij,level) {
+    var maxSize = (1<<level);
+    if (ij[0]>=0 && ij[1]>=0 && ij[0]<maxSize && ij[1]<maxSize) {
+      // no wrapping out of bounds
+      return S2.S2Cell.FromFaceIJ(face,ij,level);
+    } else {
+      // the new i,j are out of range.
+      // with the assumption that they're only a little past the borders we can just take the points as
+      // just beyond the cube face, project to XYZ, then re-create FaceUV from the XYZ vector
+
+      var st = IJToST(ij,level,[0.5,0.5]);
+      var uv = STToUV(st);
+      var xyz = FaceUVToXYZ(face,uv);
+      var faceuv = XYZToFaceUV(xyz);
+      face = faceuv[0];
+      uv = faceuv[1];
+      st = UVToST(uv);
+      ij = STToIJ(st,level);
+      return S2.S2Cell.FromFaceIJ (face, ij, level);
+    }
+  };
+
+  var face = this.face;
+  var i = this.ij[0];
+  var j = this.ij[1];
+  var level = this.level;
+
+
+  return [
+    fromFaceIJWrap(face, [i-1,j], level),
+    fromFaceIJWrap(face, [i,j-1], level),
+    fromFaceIJWrap(face, [i+1,j], level),
+    fromFaceIJWrap(face, [i,j+1], level)
+  ];
+
+};
+
+
+})();