Merge branch '10-difference' into 'dev'

Resolve "Difference"

See merge request !30

index.html

@@ -106,6 +106,17 @@
                                 <path d="M16 8A8 8 0 1 1 0 8a8 8 0 0 1 16 0zM5.354 4.646a.5.5 0 1 0-.708.708L7.293 8l-2.647 2.646a.5.5 0 0 0 .708.708L8 8.707l2.646 2.647a.5.5 0 0 0 .708-.708L8.707 8l2.647-2.646a.5.5 0 0 0-.708-.708L8 7.293 5.354 4.646z"/>
                             </svg>
                         </div>
+
+                        <p>Which layer do you want to remove features from:</p>
+                        <select id="differenceSelect_1"></select>
+
+                        <p>Which layer do you want to remove from the first one:</p>
+                        <select id="differenceSelect_2"></select>
+
+                        <p>Choose a name for the new layer:</p>
+                        <input id="differenceName"><br>
+
+                        <button class="button" style="font-size: 25px;" onclick="difference()">Differ</button>
                     </div>
 
                     <div id="dissolveBox" class="box">
@@ -209,6 +220,8 @@
         <script src="javascript/leafletLayerControl.js"></script>
         <script src="javascript/buffer.js"></script>
         <script src="javascript/dissolve.js"></script>
+        <script src="javascript/difference.js"></script>
+        <script src="javascript/turfFormatConverter.js"></script>
 
         <!-- Imported js -->
         <!-- <script src="https://unpkg.com/shpjs@latest/dist/shp.js"></script> -->

javascript/buffer.js

@@ -24,7 +24,8 @@ function makeBuffer() {
         handleLayer(name);
         document.getElementById("bufferDistance").value = "";
         document.getElementById("bufferName").value = "";
+        fillSelect("bufferSelect");
     } catch(failure) {
         alert(failure);
     }
-}
\ No newline at end of file
+}

javascript/difference.js

+function difference() {
+    var input1 = document.getElementById("differenceSelect_1").value;
+    var layer1 = overlayMaps[input1].toGeoJSON();
+    var input2 = document.getElementById("differenceSelect_2").value;
+    var layer2 = overlayMaps[input2].toGeoJSON();
+    var name = document.getElementById("differenceName").value;
+
+    // Må konverteres fra feature collection til multipolygon:
+    var coords1 = featureCollectionToMultiPolygon(layer1);
+    var coords2 = featureCollectionToMultiPolygon(layer2);
+    
+    var multiPolygon1 = turf.multiPolygon(coords1);
+    var multiPolygon2 = turf.multiPolygon(coords2);
+
+    try {
+        var difference = turf.difference(multiPolygon1, multiPolygon2);
+        var newLayer = L.geoJSON(difference);
+        
+        overlayMaps[name] = newLayer;
+
+        updateSidebar();
+        handleLayer(name);
+        document.getElementById("differenceName").value = "";
+        fillDifferenceSelect();
+    } catch(failure) {
+        alert(failure)
+    }
+}

javascript/dissolve.js

@@ -13,7 +13,8 @@ function dissolve() {
         handleLayer(name);
         document.getElementById("dissolveSelect").value = "";
         document.getElementById("dissolveName").value = "";
+        fillSelect("dissolveSelect");
     } catch(failure) {
         alert(failure);
     }
-}
\ No newline at end of file
+}

javascript/sidebar&boxes.js

@@ -28,6 +28,8 @@ function openBox(id) {
     // Fyller aktuell select med alternativ avhengig av hvilken boks en åpner:
     if (id == "bufferBox") {
         fillSelect("bufferSelect");
+    } else if (id == "differenceBox") {
+        fillDifferenceSelect();
     } else if (id == "dissolveBox") {
         fillSelect("dissolveSelect");
     }
@@ -59,4 +61,17 @@ function fillSelect(id) {
     for (key in overlayMaps) {
         select.add(new Option(text = key, value = key));
     }
-}
\ No newline at end of file
+}
+
+function fillDifferenceSelect() {
+    var select1 = document.getElementById("differenceSelect_1");
+    var select2 = document.getElementById("differenceSelect_2");
+    
+    select1.innerHTML = "";
+    select2.innerHTML = "";
+
+    for (key in overlayMaps) {
+        select1.add(new Option(text = key, value = key));
+        select2.add(new Option(text = key, value = key));
+    }
+}

javascript/turfFormatConverter.js

+/*
+Henter ut koordinatene fra GeoJSON-lag slik at en kan
+konvertere mellom feature collections og format godtatt av turf
+*/
+
+function featureCollectionToMultiPolygon(layer) { // layer er her et GeoJSON-lag
+    if (layer["type"] == "FeatureCollection") {
+        var liste = [];
+        var features = layer["features"]
+
+        for (var i = 0; i < features.length; i++) {
+            liste.push(features[i]["geometry"]["coordinates"]);
+        }
+        return liste;
+    }
+}
\ No newline at end of file