From d2fe76f736ddfee4173282ccbaf4dca89d919e26 Mon Sep 17 00:00:00 2001
From: Nils Schneider <nils@nilsschneider.net>
Date: Tue, 31 Mar 2015 21:18:06 +0200
Subject: [PATCH] pan/zoom in forcelayout

---
 lib/forcegraph.js     | 92 ++++++++++++++++++++++++++++++++++---------
 scss/_forcegraph.scss |  5 +++
 scss/main.scss        |  5 ++-
 3 files changed, 83 insertions(+), 19 deletions(-)

diff --git a/lib/forcegraph.js b/lib/forcegraph.js
index 681ecec..50a3b22 100644
--- a/lib/forcegraph.js
+++ b/lib/forcegraph.js
@@ -1,13 +1,9 @@
-// TODO
-// - window size
-// - avoid sidebar
-// - pan to node
-// - pan and zoom to link
 define(["d3"], function (d3) {
    return function (linkScale, sidebar, router) {
     var self = this
     var vis, link, node, label
     var nodesDict, linksDict
+    var zoomBehavior
     var force
 
     function nodeName(d) {
@@ -34,9 +30,51 @@ define(["d3"], function (d3) {
     }
 
     function panzoom() {
-      vis.attr("transform",
-          "translate(" + d3.event.translate + ") "
-          + "scale(" + d3.event.scale + ")")
+      var translate = zoomBehavior.translate()
+      var scale = zoomBehavior.scale()
+      vis.attr("transform", "translate(" + translate + ") " +
+                            "scale(" + scale + ")")
+    }
+
+    function panzoomTo(a, b) {
+      var sidebarWidth = sidebar.getWidth()
+      var size = force.size()
+
+      var targetWidth = Math.max(1, b[0] - a[0])
+      var targetHeight = Math.max(1, b[1] - a[1])
+
+      var scaleX = size[0] / targetWidth
+      var scaleY = size[1] / targetHeight
+      var scaleMax = zoomBehavior.scaleExtent()[1]
+      var scale = 0.5 * Math.min(scaleMax, Math.min(scaleX, scaleY))
+
+      var centroid = [(a[0] + b[0]) / 2, (a[1] + b[1]) / 2]
+      var x = -centroid[0] * scale + size[0] / 2
+      var y = -centroid[1] * scale + size[1] / 2
+      var translate = [x + sidebarWidth, y]
+
+      zoomBehavior.scale(scale)
+      zoomBehavior.translate(translate)
+
+      vis.transition().duration(500)
+         .attr("transform", "translate(" + translate + ") " +
+                            "scale(" + scale + ")")
+    }
+
+    function resize(initial) {
+      var sidebarWidth = sidebar.getWidth()
+      var width = el.offsetWidth - sidebarWidth
+      var height = el.offsetHeight
+
+      if (initial === true) {
+        var translate = zoomBehavior.translate()
+        translate[0] += sidebarWidth
+        zoomBehavior.translate(translate)
+      }
+
+      force.size([width, height])
+      force.start()
+      panzoom()
     }
 
     function tickEvent() {
@@ -59,9 +97,13 @@ define(["d3"], function (d3) {
     el.classList.add("graph")
     self.div = el
 
+    zoomBehavior = d3.behavior.zoom()
+                     .scaleExtent([1/3, 3])
+                     .on("zoom", panzoom)
+
     vis = d3.select(el).append("svg")
                 .attr("pointer-events", "all")
-                .call(d3.behavior.zoom().on("zoom", panzoom))
+                .call(zoomBehavior)
                 .append("g")
 
     vis.append("g").attr("class", "links")
@@ -69,13 +111,9 @@ define(["d3"], function (d3) {
     vis.append("g").attr("class", "labels").attr("pointer-events", "none")
 
     force = d3.layout.force()
-              .size([500, 500])
-              .charge(-100)
+              .charge(-70)
               .gravity(0.05)
-              .friction(0.73)
-              .theta(0.8)
               .linkDistance(70)
-              .linkStrength(0.2)
               .on("tick", tickEvent)
 
     var draggableNode = d3.behavior.drag()
@@ -83,6 +121,8 @@ define(["d3"], function (d3) {
                           .on("drag", dragmove)
                           .on("dragend", dragend)
 
+    window.addEventListener("resize", resize)
+
     self.setData = function (data) {
       var links = data.graph.links.filter( function (d) {
         return !d.vpn
@@ -111,7 +151,7 @@ define(["d3"], function (d3) {
 
       link.each( function (d) {
         if (d.source.node && d.target.node)
-          linksDict[linkId(d)] = this
+          linksDict[linkId(d)] = d
       })
 
       var nodes = data.graph.nodes
@@ -144,7 +184,7 @@ define(["d3"], function (d3) {
 
       node.each( function (d) {
         if (d.node)
-          nodesDict[d.node.nodeinfo.node_id] = this
+          nodesDict[d.node.nodeinfo.node_id] = d
       })
 
       label = vis.select("g.labels")
@@ -181,10 +221,13 @@ define(["d3"], function (d3) {
 
       node.selectAll("title").text(nodeName)
 
+
       force.nodes(nodes)
            .links(links)
-           .alpha(0.1)
-           .start()
+
+      resize(true)
+
+      force.start()
     }
 
     self.resetView = function () {
@@ -197,6 +240,11 @@ define(["d3"], function (d3) {
       node.classed("highlight", function (e) {
         return e.node === d && d !== undefined
       })
+
+      var n = nodesDict[d.nodeinfo.node_id]
+
+      if (n)
+        panzoomTo([n.x, n.y], [n.x, n.y])
     }
 
     self.gotoLink = function (d) {
@@ -204,6 +252,14 @@ define(["d3"], function (d3) {
       link.classed("highlight", function (e) {
         return e === d && d !== undefined
       })
+
+      var l = linksDict[linkId(d)]
+
+      if (l) {
+        var x = d3.extent([l.source, l.target], function (d) { return d.x })
+        var y = d3.extent([l.source, l.target], function (d) { return d.y })
+        panzoomTo([x[0], y[0]], [x[1], y[1]])
+      }
     }
 
     return self
diff --git a/scss/_forcegraph.scss b/scss/_forcegraph.scss
index 29e7678..7d186fd 100644
--- a/scss/_forcegraph.scss
+++ b/scss/_forcegraph.scss
@@ -55,3 +55,8 @@
   }
 }  
 
+@media screen and (max-width: $minscreenwidth) {
+  .graph {
+    height: 60vh;
+  }
+}
diff --git a/scss/main.scss b/scss/main.scss
index 178edc8..16f59f6 100644
--- a/scss/main.scss
+++ b/scss/main.scss
@@ -1,5 +1,8 @@
 @import '_leaflet';
 @import '_leaflet.label';
+
+$minscreenwidth: 60em;
+
 @import '_forcegraph';
 
 .stroke-first {
@@ -284,7 +287,7 @@ button.close:after {
   }
 }
 
-@media screen and (max-width: 60em) {
+@media screen and (max-width: $minscreenwidth) {
   .sidebar .container {
     overflow: visible;
     height: auto;