Multi Polygon function

geojson-utils.js

@@ -105,6 +105,34 @@
     return insidePoly
   }
 
+  // support multi (but not donut) polygons
+  gju.pointInMultiPolygon = function (p, poly) {
+    var coords_array = (poly.type == "MultiPolygon") ? [ poly.coordinates ] : poly.coordinates
+
+    var insideBox = false
+    var insidePoly = false
+    for (var i = 0; i < coords_array.length; i++){
+      var coords = coords_array[i];
+      for (var j = 0; j < coords.length; j++) {
+        if (!insideBox){
+          if (gju.pointInBoundingBox(p, boundingBoxAroundPolyCoords(coords[j]))) {
+            insideBox = true
+          }
+        }
+      }
+      if (!insideBox) return false
+      for (var j = 0; j < coords.length; j++) {
+        if (!insidePoly){
+          if (pnpoly(p.coordinates[1], p.coordinates[0], coords[j])) {
+            insidePoly = true
+          }
+        }
+      }
+    }
+
+    return insidePoly
+  }
+
   gju.numberToRadius = function (number) {
     return number * Math.PI / 180;
   }

test.js

@@ -50,4 +50,15 @@ poly = {"type": "Polygon", "coordinates": [[[0, 2], [2, 2], [2,0]]]};
 
 if (gju.pointInPolygon(point,poly)) throw new Error();
 
+var singlepoint = {"type": "Point", "coordinates": [-1, -1]};
+var multipoly = {"type": "MultiPolygon",
+			        "coordinates": [ 
+			        	[ [ [0,0],[0,10],[10,10],[10,0],[0,0] ] ] , 
+			        	[ [ [10,10],[10,20],[20,20],[20,10],[10,10] ] ] 
+			        ]
+			    };
+
+if (!gju.pointInMultiPolygon(point,multipoly)) throw new Error();
+if (gju.pointInMultiPolygon(singlepoint,multipoly)) throw new Error();
+
 console.log('all passed')