fixing approximation module

web/app/brep/approx.js

@@ -0,0 +1,66 @@
+const FACE_CHUNK = 'approx.face.chunk';
+const EDGE_CHUNK = 'approx.edge.chunk';
+const EDGE_AUX = 'approx.edge.aux';
+
+class ApproxSurface {
+  constructor() {
+    this.faces = [];   
+  }
+  
+  addFace(face) {
+    face.data[FACE_CHUNK] = this;
+    this.faces.push(face);
+  }
+}
+
+class ApproxCurve {
+  constructor(surface1, surface2) {
+    this.surface1 = surface1;
+    this.surface2 = surface2;
+    this.edges = [];
+  }
+
+  addEdge(edge) {
+    this.edges.push(edge);
+    edge.data[EDGE_CHUNK] = this;
+  }
+  
+  equals(other) {
+    return other instanceof ApproxCurve &&
+        
+      ((this.surface1 == other.surface1 &&
+        this.surface2 == other.surface2) ||
+          
+       (this.surface1 == other.surface2 &&
+        this.surface2 == other.surface1)
+      )
+  }
+}
+
+function update(shell) {
+  const index = new DoubleKeyMap();
+  for (let e of shell.edges) {
+    const face1 = e.halfEdge1.loop.face;
+    const face2 = e.halfEdge2.loop.face;
+    const approxSurface1 = face1.data[FACE_CHUNK];
+    const approxSurface2 = face2.data[FACE_CHUNK];
+    if (approxSurface1 !== undefined && approxSurface1 === approxSurface2) {
+      e.data[EDGE_AUX] = approxSurface1;
+    } else if (approxSurface1 !== undefined || approxSurface2 !== undefined ) {
+      const o1 = approxSurface1 !== undefined ? approxSurface1 : face1.surface;
+      const o2 = approxSurface2 !== undefined ? approxSurface2 : face2.surface;
+      const approxCurve = getCurve(index, o1, o2);
+      approxCurve.addEdge(e);
+    } 
+  }
+}
+
+function getCurve(index, o1, o2) {
+  let curve = index.get(o1, o2);
+  if (curve == null) {
+    curve = new ApproxCurve(o1, o2);
+    index.set(o1, o2, curve);
+  }
+  return curve;
+}
+

web/app/utils/utils.js

@@ -66,3 +66,36 @@ export function camelCaseSplit(str) {
   }
   return words;
 }
+
+export class DoubleKeyMap {
+
+  constructor() {
+    this.map = new Map();
+  }
+
+  get(a, b) {
+    let subMap = this.map.get(a);
+    if (subMap == null) {
+      subMap = this.map.get(b);
+      if (subMap != null) {
+        return subMap.get(a);;
+      }
+      return null;
+    }
+    subMap.get(b);
+  }
+
+  set(a, b, value) {
+    let subMap = this.map.get(a);
+    if (subMap == null) {
+      subMap = this.map.get(b);
+      if (subMap != null) {
+        subMap.set(a, value);
+        return;
+      }
+      subMap = new Map();
+      this.map.set(a, subMap);
+    } 
+    subMap.set(b, value);
+  }
+}