tilebelt - npm Package Compare versions

Comparing version 0.6.1 to 0.7.0

index.js

@@ -170,2 +170,17 @@ // a tile is an array [x,y,z]
 
+function pointToTileFraction (lon, lat, z) {
+    var tile = pointToTile(lon, lat, z);
+    var bbox = tileToBBOX(tile);
+
+    var xTileOffset = bbox[2] - bbox[0];
+    var xPointOffset = lon - bbox[0];
+    var xPercentOffset = xPointOffset / xTileOffset;
+
+    var yTileOffset = bbox[1] - bbox[3];
+    var yPointOffset = lat - bbox[3];
+    var yPercentOffset = yPointOffset / yTileOffset;
+
+    return [tile[0]+xPercentOffset, tile[1]+yPercentOffset, z];
+}
+
 module.exports = {
@@ -183,3 +198,4 @@ tileToGeoJSON: tileToGeoJSON,
     pointToTile: pointToTile,
-    bboxToTile: bboxToTile
+    bboxToTile: bboxToTile,
+    pointToTileFraction: pointToTileFraction
 };

package.json

 {
   "name": "tilebelt",
-  "version": "0.6.1",
+  "version": "0.7.0",
   "description": "simple tile utilities",
@@ -5,0 +5,0 @@ "main": "index.js",

README.md

@@ -26,2 +26,3 @@ tilebelt
 tileToGeoJSON(tile) | get a geojson representation of a tile
+tileToBBOX(tile) | get the bbox of a tile
 getChildren(tile) | get the 4 tiles one zoom level higher
@@ -36,2 +37,3 @@ getParent(tile) | get the tile one zoom level lower
 pointToTile(lon, lat, zoom) | get the tile for a point at a specified zoom level
+pointToTileFraction(lon, lat, zoom) | get the precise fractional tile location for a point at a zoom level
 
@@ -38,0 +40,0 @@ ##tests

test.js

@@ -173,2 +173,11 @@ var test = require('tape'),
     t.end();
+});
+
+test('pointToTileFraction', function(t) {
+    var tile = tilebelt.pointToTileFraction(-95.93965530395508,41.26000108568697,9);
+    t.ok(tile, 'convert point to tile fraction');
+    t.equal(tile[0], 119.552490234375);
+    t.equal(tile[1], 191.4701834281966);
+    t.equal(tile[2], 9);
+    t.end();
 });

No alert changes

Improved metrics

Total package byte prevSize

13376

7.64%

Lines of code

331

6.43%

Number of lines in readme file

41

5.13%

No dependency changes