Add weighted cross-chord edges: 100x weaker than regular edges

webapp/path_navigator.html

@@ -46,18 +46,23 @@
           });
         });
 
-        const edgeList = edges.map(e => ({ s: e.source().id(), t: e.target().id() }));
+        const edgeList = edges.map(e => ({ 
+          s: e.source().id(), 
+          t: e.target().id(),
+          isCrossChord: e.data('isCrossChord')
+        }));
 
         const iter = (i) => {
           state.forEach(s => s.fx = 0);
 
-          edgeList.forEach(({s,t})=>{
+          edgeList.forEach(({s, t, isCrossChord})=>{
             const a = state.get(s), b = state.get(t);
             if(!a || !b) return;
             const dx = b.x - a.x;
             const dist = Math.abs(dx) || 0.0001;
             const dir = dx / dist;
-            const spring = opts.linkStrength * (dist - opts.linkDistance);
+            const strength = isCrossChord ? (opts.crossChordStrength || 0.001) : opts.linkStrength;
+            const spring = strength * (dist - opts.linkDistance);
             a.fx += spring * dir;
             b.fx -= spring * dir;
           });
@@ -350,8 +355,8 @@
                     {
                         selector: 'edge',
                         style: {
-                            'width': 1.5,
+                            'width': 2.5,
-                            'line-color': '#555555',
+                            'line-color': '#ffffff',
                             'curve-style': 'straight',
                             'target-arrow-shape': 'none',
                             'label': 'data(ratio)',
@@ -364,6 +369,17 @@
                             'text-background-padding': '2px',
                         }
                     },
+                    {
+                        selector: 'edge[isCrossChord = "true"]',
+                        style: {
+                            'width': 1,
+                            'line-color': '#aaaaaa',
+                            'line-style': 'dashed',
+                            'curve-style': 'straight',
+                            'target-arrow-shape': 'none',
+                            'label': '',
+                        }
+                    },
                     {
                         selector: ':selected',
                         style: {
@@ -479,6 +495,33 @@
             // Build elements array for all chords
             let elements = [];
             
+            // Collect cross-chord edges (same hs_array between adjacent chords)
+            const crossChordEdges = [];
+            for (let chordIdx = 1; chordIdx < allGraphsData.graphs.length; chordIdx++) {
+                const prevGraph = allGraphsData.graphs[chordIdx - 1];
+                const currGraph = allGraphsData.graphs[chordIdx];
+                if (!prevGraph || !prevGraph.nodes || !currGraph || !currGraph.nodes) continue;
+                
+                currGraph.nodes.forEach(n => {
+                    const prevNode = prevGraph.nodes.find(pn => 
+                        JSON.stringify(pn.hs_array) === JSON.stringify(n.hs_array)
+                    );
+                    if (prevNode) {
+                        const prevNodeId = `c${chordIdx - 1}_${prevNode.id}`;
+                        const currNodeId = `c${chordIdx}_${n.id}`;
+                        crossChordEdges.push({
+                            group: 'edges',
+                            data: {
+                                source: prevNodeId,
+                                target: currNodeId,
+                                ratio: "1/1",
+                                isCrossChord: "true"
+                            },
+                        });
+                    }
+                });
+            }
+            
             allGraphsData.graphs.forEach((graph, chordIdx) => {
                 if (!graph || !graph.nodes) return;
                 
@@ -527,6 +570,9 @@
             
             if (elements.length === 0) return;
             
+            // Add cross-chord edges to elements BEFORE layout (so xforce considers them)
+            elements.push(...crossChordEdges);
+            
             // Add all elements
             cy.add(elements);
             console.log('Added', elements.length, 'elements');
@@ -544,16 +590,19 @@
             });
             
             // Run xforce layout to optimize x positions while keeping y fixed
-            cy.layout({
+            const layout = cy.layout({
                 name: 'xforce',
                 linkDistance: 60,
                 linkStrength: 0.1,
+                crossChordStrength: 0.00005,
                 charge: -60,
                 collisionDistance: 35,
                 damping: 0.7,
                 iterations: 250,
                 bounds: bounds,
-            }).run();
+            });
+            
+            layout.run();
             
             // Set canvas size
             cy.style().json()[0].value = graphWidth;