Do not include any part for which no points are within the main building (#138)

Author: Beakerboy

README.md

@@ -33,12 +33,13 @@ Roof Types:
  * Dome
  * Pyramidal
  * Gabled
+ * Hipped
 
 Examples:
  * Simple building with no parts - [Washington Monument](https://beakerboy.github.io/OSMBuilding/index.html?id=766761337)
  * Glass - [Petronas Towers](https://beakerboy.github.io/OSMBuilding/index.html?id=279944536)
  * Dome roof, Gabled roof, and Skillion ramp - [Jefferson Memorial](https://beakerboy.github.io/OSMBuilding/index.html?type=relation&id=3461570)
- * Dome, Gabled, and Pyramidal Roof - [US Capitol](https://beakerboy.github.io/OSMBuilding/index.html?type=relation&id=12286916)
+ * Dome, Gabled, Hipped, and Pyramidal Roof - [US Capitol](https://beakerboy.github.io/OSMBuilding/index.html?type=relation&id=12286916)
  * [Chrysler Building](https://beakerboy.github.io/OSMBuilding/index.html?id=42500770)
  * Building Relation [Burj Khalifa](https://beakerboy.github.io/OSMBuilding/index.html?type=relation&id=7584462)
  * Multipolygon with no parts - [Freer Art Gallery](https://beakerboy.github.io/OSMBuilding/index.html?type=relation&id=1029355)

src/building.js

@@ -206,10 +206,13 @@ class Building {
     } else {
       // Filter to all ways
       var parts = this.fullXmlData.getElementsByTagName('way');
-      for (let j = 0; j < parts.length; j++) {
-        if (parts[j].querySelector('[k="building:part"]')) {
-          const id = parts[j].getAttribute('id');
-          this.parts.push(new BuildingPart(id, this.fullXmlData, this.nodelist, this.outerElement.options));
+      for (const xmlPart of parts) {
+        if (xmlPart.querySelector('[k="building:part"]')) {
+          const id = xmlPart.getAttribute('id');
+          const part = new BuildingPart(id, this.fullXmlData, this.nodelist, this.outerElement.options);
+          if (this.partIsInside(part)) {
+            this.parts.push(part);
+          }
         }
       }
       // Filter all relations
@@ -408,5 +411,22 @@ class Building {
       }
     }
   }
+
+  /**
+   * Check if any point in a part is within this building's outline.
+   * It only checknof points are inside, not if crossing events occur, or
+   * if the part completly surrounds the building.
+   * @param {BuildingPart} part - the part to be tested
+   * @returns {bool} is it?
+   */
+  partIsInside(part) {
+    const shape = part.shape;
+    for (const vector of shape.extractPoints().shape) {
+      if (BuildingShapeUtils.surrounds(this.outerElement.shape, [vector.x, vector.y])) {
+        return true;
+      }
+    }
+    return false;
+  }
 }
 export {Building};

src/extras/BuildingShapeUtils.js

@@ -24,7 +24,6 @@ class BuildingShapeUtils extends ShapeUtils {
     const elements = way.getElementsByTagName('nd');
 
     // Get the coordinates of all the nodes and add them to the shape outline.
-
     for (const element of elements) {
       ref = element.getAttribute('ref');
       nodes.push(nodelist[ref]);

test/building.test.js

@@ -315,6 +315,36 @@ test('Test downloading type=building with multipolygon outline and multiple inne
   expect(global.fetch.mock.calls[2][0]).toBe(urlBase + 'map?bbox=30.4980057,59.9380365,30.4993839,59.9385087');
 });
 
+test('Part must be within outline', () => {
+  const data = `<?xml version="1.0" encoding="UTF-8"?>
+<osm>
+ <node id="1" lat="0.001" lon="0.001"/>
+ <node id="2" lat="0.001" lon="0"/>
+ <node id="3" lat="0" lon="0"/>
+ <node id="4" lat="0" lon=".0005"/>
+ <node id="5" lat="0" lon=".001"/>
+ <node id="6" lat=".0001" lon=".001"/>
+ <node id="7" lat=".0001" lon="0.005"/>
+ <way id="11">
+  <nd ref="1"/>
+  <nd ref="2"/>
+  <nd ref="3"/>
+  <nd ref="1"/>
+  <tag k="building" v="apartments"/>
+ </way>
+ <way id="22">
+  <nd ref="4"/>
+  <nd ref="5"/>
+  <nd ref="6"/>
+  <nd ref="7"/>
+  <nd ref="4"/>
+  <tag k="building:part" v="yes"/>
+ </way>
+</osm>
+`;
+  expect(new Building('11', data).parts.length).toBe(0);
+});
+
 window.printError = printError;
 
 var errors = [];