Mon 21 Jul 22:43:21 CEST 2025

js/ui/mxgraph/src/js/layout/mxEdgeLabelLayout.js

@@ -0,0 +1,165 @@
+/**
+ * Copyright (c) 2006-2015, JGraph Ltd
+ * Copyright (c) 2006-2015, Gaudenz Alder
+ */
+/**
+ * Class: mxEdgeLabelLayout
+ * 
+ * Extends <mxGraphLayout> to implement an edge label layout. This layout
+ * makes use of cell states, which means the graph must be validated in
+ * a graph view (so that the label bounds are available) before this layout
+ * can be executed.
+ * 
+ * Example:
+ * 
+ * (code)
+ * var layout = new mxEdgeLabelLayout(graph);
+ * layout.execute(graph.getDefaultParent());
+ * (end)
+ * 
+ * Constructor: mxEdgeLabelLayout
+ *
+ * Constructs a new edge label layout.
+ *
+ * Arguments:
+ * 
+ * graph - <mxGraph> that contains the cells.
+ */
+function mxEdgeLabelLayout(graph, radius)
+{
+	mxGraphLayout.call(this, graph);
+};
+
+/**
+ * Extends mxGraphLayout.
+ */
+mxEdgeLabelLayout.prototype = new mxGraphLayout();
+mxEdgeLabelLayout.prototype.constructor = mxEdgeLabelLayout;
+
+/**
+ * Function: execute
+ * 
+ * Implements <mxGraphLayout.execute>.
+ */
+mxEdgeLabelLayout.prototype.execute = function(parent)
+{
+	var view = this.graph.view;
+	var model = this.graph.getModel();
+	
+	// Gets all vertices and edges inside the parent
+	var edges = [];
+	var vertices = [];
+	var childCount = model.getChildCount(parent);
+	
+	for (var i = 0; i < childCount; i++)
+	{
+		var cell = model.getChildAt(parent, i);
+		var state = view.getState(cell);
+		
+		if (state != null)
+		{
+			if (!this.isVertexIgnored(cell))
+			{
+				vertices.push(state);
+			}
+			else if (!this.isEdgeIgnored(cell))
+			{
+				edges.push(state);
+			}
+		}
+	}
+	
+	this.placeLabels(vertices, edges);
+};
+
+/**
+ * Function: placeLabels
+ * 
+ * Places the labels of the given edges.
+ */
+mxEdgeLabelLayout.prototype.placeLabels = function(v, e)
+{
+	var model = this.graph.getModel();
+	
+	// Moves the vertices to build a circle. Makes sure the
+	// radius is large enough for the vertices to not
+	// overlap
+	model.beginUpdate();
+	try
+	{
+		for (var i = 0; i < e.length; i++)
+		{
+			var edge = e[i];
+			
+			if (edge != null && edge.text != null &&
+				edge.text.boundingBox != null)
+			{
+				for (var j = 0; j < v.length; j++)
+				{
+					var vertex = v[j];
+					
+					if (vertex != null)
+					{
+						this.avoid(edge, vertex);
+					}
+				}
+			}
+		}
+	}
+	finally
+	{
+		model.endUpdate();
+	}
+};
+
+/**
+ * Function: avoid
+ * 
+ * Places the labels of the given edges.
+ */
+mxEdgeLabelLayout.prototype.avoid = function(edge, vertex)
+{
+	var model = this.graph.getModel();
+	var labRect = edge.text.boundingBox;
+	
+	if (mxUtils.intersects(labRect, vertex))
+	{
+		var dy1 = -labRect.y - labRect.height + vertex.y;
+		var dy2 = -labRect.y + vertex.y + vertex.height;
+		
+		var dy = (Math.abs(dy1) < Math.abs(dy2)) ? dy1 : dy2;
+		
+		var dx1 = -labRect.x - labRect.width + vertex.x;
+		var dx2 = -labRect.x + vertex.x + vertex.width;
+	
+		var dx = (Math.abs(dx1) < Math.abs(dx2)) ? dx1 : dx2;
+		
+		if (Math.abs(dx) < Math.abs(dy))
+		{
+			dy = 0;
+		}
+		else
+		{
+			dx = 0;
+		}
+	
+		var g = model.getGeometry(edge.cell);
+		
+		if (g != null)
+		{
+			g = g.clone();
+			
+			if (g.offset != null)
+			{
+				g.offset.x += dx;
+				g.offset.y += dy;
+			}
+			else
+			{
+				g.offset = new mxPoint(dx, dy);
+			}
+			
+			model.setGeometry(edge.cell, g);
+		}
+	}
+};