geohash-poly - npm Package Compare versions

Comparing version 0.3.0 to 0.4.0

index.js

@@ -6,3 +6,4 @@ var Readable = require('stream').Readable,
   through2 = require('through2'),
-  async = require('async');
+  async = require('async'),
+  geojsonArea = require('geojson-area');
 
@@ -40,3 +41,4 @@ /**
     splitAt: 2000,
-    hashMode: 'inside'
+    hashMode: 'inside',
+    threshold: 0
   };
@@ -148,3 +150,7 @@ options = options || {};
       while (columnHash != westerly) {
-        if(self.hashMode !== 'inside' || inside(columnCenter, prepared)) rowHashes.push(columnHash);
+        if(self.hashMode === 'inside' && inside(columnCenter, prepared)) {
+          rowHashes.push(columnHash);
+        } else if (self.hashMode === 'intersect' || self.hashMode === 'extent') {
+          rowHashes.push(columnHash);
+        }
         columnHash = geohash.neighbor(columnHash, [0, 1]);
@@ -166,4 +172,33 @@ columnCenter = geohash.decode(columnHash);
       }
-      done(null, rowHashes);
 
+      if(self.hashMode === 'inside' || self.hashMode === 'extent' || !rowHashes.length) {
+        done(null, rowHashes);
+      } else if (self.hashMode === 'intersect') {
+
+        var baseArea = null;
+        async.filter(rowHashes, function (h, cb) {
+          var bb = geohash.decode_bbox(h);
+          bb = turf.polygon([[
+                [bb[1], bb[2]],
+                [bb[3], bb[2]],
+                [bb[3], bb[0]],
+                [bb[1], bb[0]],
+                [bb[1], bb[2]]
+              ]]);
+
+          if(!baseArea) baseArea = geojsonArea.geometry(bb.geometry);
+
+          turf.intersect(turf.featurecollection([turf.polygon(prepared.coordinates)]), turf.featurecollection([bb]), function (err, intersected) {
+            var keepIntersection = !self.threshold ? true : false;
+            if(self.threshold && intersected.features.length && (intersected.features[0].type === 'Polygon' || intersected.features[0].type === 'MultiPolygon')) {
+              var intersectedArea = geojsonArea.geometry(intersected.features[0]);
+              keepIntersection = baseArea && intersectedArea / baseArea >= self.threshold;
+            }
+            cb(keepIntersection);
+          });
+        }, function (results) {
+          done(null, results);
+        });
+      }
+
     });
@@ -213,4 +248,5 @@ };
     rowMode: options.rowMode ? true : false,
-    hashMode: options.hashMode
+    hashMode: options.hashMode,
+    threshold: options.threshold
   });
 };

package.json

 {
   "name": "geohash-poly",
-  "version": "0.3.0",
+  "version": "0.4.0",
   "description": "Transform a GeoJSON Polygon or MultiPolygon to a list of geohashes that form it.",
@@ -22,3 +22,4 @@ "main": "index.js",
     "async": "~0.2.10",
-    "through2": "~0.4.0"
+    "through2": "~0.4.0",
+    "geojson-area": "^0.1.0"
   },
@@ -25,0 +26,0 @@ "devDependencies": {

README.md

@@ -72,1 +72,2 @@ # Geohash-poly
 - `'extent'`: return all hashes which make up the bounding box of the shape.
+- `'intersect'`: return all hashes that intersect with the shape. Use the `'threshold'` option to specify a percentage of least coverage. See `examples/streaming.js`.

No alert changes

Improved metrics

Total package byte prevSize

241142

increased by0.9%

Lines of code

840

increased by6.87%

Worsened metrics

Dependency count

6

increased by20%

Dependency changes

• + Addedgeojson-area@^0.1.0

• + Addedgeojson-area@0.1.0(transitive)

• + Addedwgs84@0.0.0(transitive)