From 3e63b6432e16658d802e9e923295a592fcfb7d83 Mon Sep 17 00:00:00 2001
From: Martin Geno <geno+dev@fireorbit.de>
Date: Fri, 14 Apr 2017 20:43:03 +0200
Subject: [PATCH] [TASK] Add animation & improve behaviour of forcegraph

---
 lib/forcegraph.js | 97 ++++++++++++++++++++++++++++++++---------------
 1 file changed, 67 insertions(+), 30 deletions(-)

diff --git a/lib/forcegraph.js b/lib/forcegraph.js
index 4b28245..2cc5d34 100644
--- a/lib/forcegraph.js
+++ b/lib/forcegraph.js
@@ -1,5 +1,5 @@
-define(['d3-selection', 'd3-force', 'd3-zoom', 'd3-drag', 'utils/math', 'forcegraph/draw'],
-  function (d3Selection, d3Force, d3Zoom, d3Drag, math, draw) {
+define(['d3-selection', 'd3-force', 'd3-zoom', 'd3-drag', 'd3-timer', 'd3-ease', 'd3-interpolate', 'utils/math', 'forcegraph/draw'],
+  function (d3Selection, d3Force, d3Zoom, d3Drag, d3Timer, d3Ease, d3Interpolate, math, draw) {
     'use strict';
 
     return function (config, linkScale, sidebar, router) {
@@ -14,10 +14,12 @@ define(['d3-selection', 'd3-force', 'd3-zoom', 'd3-drag', 'utils/math', 'forcegr
       var intNodes = [];
       var dictNodes = {};
       var intLinks = [];
+      var movetoTimer;
 
       var NODE_RADIUS_DRAG = 10;
       var NODE_RADIUS_SELECT = 15;
       var LINK_RADIUS_SELECT = 12;
+      var ZOOM_ANIMATE_DURATION = 350;
 
       var ZOOM_MIN = 1 / 8;
       var ZOOM_MAX = 3;
@@ -32,9 +34,43 @@ define(['d3-selection', 'd3-force', 'd3-zoom', 'd3-drag', 'utils/math', 'forcegr
         draw.setMaxArea(canvas.width, canvas.height);
       }
 
-      function moveTo(x, y) {
-        transform.x = (canvas.width + sidebar()) / 2 - x * transform.k;
-        transform.y = canvas.height / 2 - y * transform.k;
+      function transformPosition(p) {
+        transform.x = p.x;
+        transform.y = p.y;
+        transform.k = p.k;
+      }
+
+      function moveTo(callback, forceMove) {
+        clearTimeout(movetoTimer);
+        if (!forceMove && force.alpha() > 0.3) {
+          movetoTimer = setTimeout(function timerOfMoveTo() {
+            moveTo(callback);
+          }, 300);
+          return;
+        }
+        var result = callback();
+        var x = result[0];
+        var y = result[1];
+        var k = result[2];
+        var end = { k: k };
+
+        end.x = (canvas.width + sidebar()) / 2 - x * k;
+        end.y = canvas.height / 2 - y * k;
+
+        var start = { x: transform.x, y: transform.y, k: transform.k };
+
+        var interpolate = d3Interpolate.interpolateObject(start, end);
+
+        var timer = d3Timer.timer(function (t) {
+          if (t >= ZOOM_ANIMATE_DURATION) {
+            timer.stop();
+            return;
+          }
+
+          var v = interpolate(d3Ease.easeQuadInOut(t / ZOOM_ANIMATE_DURATION));
+          transformPosition(v);
+          window.requestAnimationFrame(redraw);
+        });
       }
 
       function onClick() {
@@ -111,7 +147,8 @@ define(['d3-selection', 'd3-force', 'd3-zoom', 'd3-drag', 'utils/math', 'forcegr
         .force('x', d3Force.forceX().strength(0.02))
         .force('y', d3Force.forceY().strength(0.02))
         .force('collide', d3Force.forceCollide())
-        .on('tick', redraw);
+        .on('tick', redraw)
+        .alphaDecay(0.015);
 
       var drag = d3Drag.drag()
         .subject(function () {
@@ -192,40 +229,40 @@ define(['d3-selection', 'd3-force', 'd3-zoom', 'd3-drag', 'utils/math', 'forcegr
       };
 
       self.resetView = function resetView() {
-        draw.setHighlight(null);
-        transform.k = (ZOOM_MIN + 1) / 2;
-        moveTo(0, 0);
-        redraw();
+        moveTo(function calcToReset() {
+          draw.setHighlight(null);
+          return [0, 0, (ZOOM_MIN + 1) / 2];
+        }, true);
       };
 
       self.gotoNode = function gotoNode(d) {
-        for (var i = 0; i < intNodes.length; i++) {
-          var n = intNodes[i];
-          if (n.o.node.nodeinfo.node_id !== d.nodeinfo.node_id) {
-            continue;
+        moveTo(function calcToNode() {
+          for (var i = 0; i < intNodes.length; i++) {
+            var n = intNodes[i];
+            if (n.o.node.nodeinfo.node_id !== d.nodeinfo.node_id) {
+              continue;
+            }
+            draw.setHighlight({ type: 'node', o: n.o.node });
+            return [n.x, n.y, (ZOOM_MAX + 1) / 2];
           }
-          draw.setHighlight({ type: 'node', o: n.o.node });
-          transform.k = (ZOOM_MAX + 1) / 2;
-          moveTo(n.x, n.y);
-          break;
-        }
-        redraw();
+          return [0, 0, (ZOOM_MIN + 1) / 2];
+        });
       };
 
       self.gotoLink = function gotoLink(d) {
-        draw.setHighlight({ type: 'link', o: d });
-        for (var i = 0; i < intLinks.length; i++) {
-          var l = intLinks[i];
-          if (l.o !== d) {
-            continue;
+        moveTo(function calcToLink() {
+          draw.setHighlight({ type: 'link', o: d });
+          for (var i = 0; i < intLinks.length; i++) {
+            var l = intLinks[i];
+            if (l.o !== d) {
+              continue;
+            }
+            return [(l.source.x + l.target.x) / 2, (l.source.y + l.target.y) / 2, (ZOOM_MAX / 2) + ZOOM_MIN];
           }
-          moveTo((l.source.x + l.target.x) / 2, (l.source.y + l.target.y) / 2);
-          break;
-        }
-        redraw();
+          return [0, 0, (ZOOM_MIN + 1) / 2];
+        });
       };
 
-
       self.gotoLocation = function gotoLocation() {
         // ignore
       };