Network: Smooth type 'dynamic' adjusted for node-specific option in hierarchical (#3130)

Fix for #3036

Option `smooth.type: dynamic` is not allowed for hierarchical layouts.
This was handled properly for the main options, but not for the node-specific options.

Options within node instances arei now checked for `smooth.type: dynamic` and replaced
by `horizontal` or `vertical`. The implementation adds listener `_adjustEdgesForHierarchicalLayout`
in `LayoutHandler`. This listener must be activated every time noder- specific options might change.
This happens in the logical places within `EdgeHandler`.

lib/network/modules/EdgesHandler.js

@@ -4,6 +4,7 @@ var DataView = require('../../DataView');
 
 var Edge = require("./components/Edge").default;
 var Label = require("./components/shared/Label").default;
+var LayoutEngine = require("./LayoutEngine").default;  // For access to LayoutEngine.getStaticType()
 
 class EdgesHandler {
   constructor(body, images, groups) {
@@ -115,11 +116,11 @@ class EdgesHandler {
 
   bindEventListeners() {
     // this allows external modules to force all dynamic curves to turn static.
-    this.body.emitter.on("_forceDisableDynamicCurves", (type) => {
+    this.body.emitter.on("_forceDisableDynamicCurves", (type, emit = true) => {
       if (type === 'dynamic') {
         type = 'continuous';
       }
-      let emitChange = false;
+      let dataChanged = false;
       for (let edgeId in this.body.edges) {
         if (this.body.edges.hasOwnProperty(edgeId)) {
           let edge = this.body.edges[edgeId];
@@ -137,18 +138,25 @@ class EdgesHandler {
                 else {
                   edge.setOptions({smooth: {type: type}});
                 }
-                emitChange = true;
+                dataChanged = true;
               }
             }
           }
         }
       }
-      if (emitChange === true) {
+      if (emit === true && dataChanged === true) {
         this.body.emitter.emit("_dataChanged");
       }
     });
 
     // this is called when options of EXISTING nodes or edges have changed.
+    //
+    // NOTE: Not true, called when options have NOT changed, for both existing as well as new nodes.
+    //       See update() for logic.
+    // TODO: Verify and examine the consequences of this. It might still trigger when
+    //       non-option fields have changed, but then reconnecting edges is still useless.
+    //       Alternatively, it might also be called when edges are removed.
+    //
     this.body.emitter.on("_dataUpdated", () => {
       this.reconnectEdges();
     });
@@ -247,6 +255,7 @@ class EdgesHandler {
       this.add(ids, true);
     }
 
+    this.body.emitter.emit('_adjustEdgesForHierarchicalLayout');
     if (doNotEmit === false) {
       this.body.emitter.emit("_dataChanged");
     }
@@ -274,6 +283,8 @@ class EdgesHandler {
       edges[id] = this.create(data);
     }
 
+    this.body.emitter.emit('_adjustEdgesForHierarchicalLayout');
+
     if (doNotEmit === false) {
       this.body.emitter.emit("_dataChanged");
     }
@@ -308,6 +319,7 @@ class EdgesHandler {
     }
 
     if (dataChanged === true) {
+      this.body.emitter.emit('_adjustEdgesForHierarchicalLayout');
       this.body.emitter.emit("_dataChanged");
     }
     else {

lib/network/modules/LayoutEngine.js

@@ -207,6 +207,16 @@ class LayoutEngine {
     this.body.emitter.on('_resetHierarchicalLayout', () => {
       this.setupHierarchicalLayout();
     });
+    this.body.emitter.on('_adjustEdgesForHierarchicalLayout', () => {
+      if (this.options.hierarchical.enabled !== true) {
+        return;
+      }
+      // get the type of static smooth curve in case it is required
+      let type = this.getStaticType();
+
+      // force all edges into static smooth curves.
+      this.body.emitter.emit('_forceDisableDynamicCurves', type, false);
+    });
   }
 
   setOptions(options, allOptions) {
@@ -275,11 +285,7 @@ class LayoutEngine {
       }
 
       // get the type of static smooth curve in case it is required
-      // NOTE: 'type' here is for the curve, so it will be orthogonal to the network direction
-      let type = 'horizontal';
-      if (!this._isVertical()) {
-        type = 'vertical';  // sic
-      }
+      let type = this.getStaticType();
 
       // disable smooth curves if nothing is defined. If smooth curves have been turned on,
       // turn them into static smooth curves.
@@ -324,7 +330,7 @@ class LayoutEngine {
       }
 
       // Force all edges into static smooth curves.
-      //Only applies to edges that do not use the global options for smooth.
+      // Only applies to edges that do not use the global options for smooth.
       this.body.emitter.emit('_forceDisableDynamicCurves', type);
     }
 
@@ -1559,6 +1565,24 @@ class LayoutEngine {
   }
 
 
+  /**
+   * Get the type of static smooth curve in case it is required.
+   *
+   * The return value is the type to use to translate dynamic curves to
+   * another type, in the case of hierarchical layout. Dynamic curves do
+   * not work for that layout type.
+   */
+  getStaticType() {
+    // Node that 'type' is the edge type, and therefore 'orthogonal' to the layout type.
+    let type = 'horizontal';
+    if (!this._isVertical()) {
+      type = 'vertical';
+    }
+
+    return type;
+  }
+
+
   /**
    * Determine the center position of a branch from the passed list of child nodes
    *