diff --git a/public/js/force-directed-graph.js b/public/js/force-directed-graph.js
index d127190..215d91e 100644
--- a/public/js/force-directed-graph.js
+++ b/public/js/force-directed-graph.js
@@ -14,7 +14,7 @@
       color = d3.scaleOrdinal(d3.schemeCategory20),
       width = +d3Canvas.attr("width"),
       height = +d3Canvas.attr("height"),
-      radius = 2.5,
+      radius = 4,
       context = canvas.getContext("2d");
 
     var simulation = d3.forceSimulation()
@@ -25,48 +25,23 @@
       .force("center", d3.forceCenter(width / 2, height / 2));
 
     // FILTER & COMMUNITY
-    var edges = [],
-      nodes = [];
-    for (var i = 0; i < graph.nodes.length; i++) {
-      nodes.push(i);
-    }
-    for (var i = 0; i < graph.links.length; i++) {
-      var edge = graph.links[i];
-      edge.weight = edge.value;
-      edges.push(edge);
-    }
+    var selectedData = getSelectedData(setGroup(graph), 4),
+      nodes = selectedData.nodes,
+      links = selectedData.links;
 
-    // Create the "community"
-    var community = jLouvain().nodes(nodes).edges(edges),
-      res = community();
-
-    // Affect community for each node
-    for (var key in res) {
-      graph.nodes[nodes[key]].group = res[key];
-    }
-
-    var deleted_links = {},
-      selectedLinks = graph.links.filter(function(d) {
-        var res = (d.value >= 10);
-        if (!res) {
-          deleted_links[d.source] = deleted_links[d.source] + 1 || 1;
-          deleted_links[d.target] = deleted_links[d.target] + 1 || 1;
-        }
-        return res;
-      }),
-      selectedNodes = graph.nodes.filter(function(d) {
-        d.value = d.value - (deleted_links[d.id] || 0);
-        var res = (d.value > 0);
-        return res;
-      });
+    // Set radius
+    nodes.forEach(function(e) {
+      e.radius = radius;
+      return e;
+    });
 
     // FILL CANVAS
     simulation
-      .nodes(selectedNodes)
+      .nodes(nodes)
       .on("tick", draw);
 
     simulation.force("link")
-      .links(selectedLinks);
+      .links(links);
 
     function draw() {
       context.save();
@@ -78,8 +53,9 @@
       context.strokeStyle = "#546e7a";
       context.beginPath();
       graph.links.forEach(function(d) {
-        context.moveTo(d.source.x, d.source.y);
-        context.lineTo(d.target.x, d.target.y);
+        context.moveTo(Math.floor(d.source.x), Math.floor(d.source.y));
+        context.lineTo(Math.floor(d.target.x), Math.floor(d.target.y));
+        context.lineWidth = 1;
       });
       context.stroke();
 
@@ -88,11 +64,12 @@
         context.beginPath(); //for each node do begin path as context fill style and stroke are different.
         context.strokeStyle = "#fff";
         context.fillStyle = color(d.group);
-        context.moveTo(d.x + radius, d.y);
-        context.arc(d.x, d.y, radius, 0, 2 * Math.PI);
+        context.rect(Math.floor(d.x - (d.radius / 2)), Math.floor(d.y - (d.radius / 2)), d.radius, d.radius);
+        // context.arc(d.x, d.y, d.radius, 0, 2 * Math.PI);
         context.fill();
         context.stroke();
       });
+
       context.restore();
     }
 
@@ -107,37 +84,43 @@
       .call(d3.zoom().scaleExtent([-100, 100]).on("zoom", zoomed))
       .call(draw);
 
-    function zoomed() {
-      transform = d3.event.transform;
-      draw();
-    }
-
-    function dragsubject() {
-      var selectedNode,
+    function detectCollision(source, targets) {
+      var result = null,
+        target,
         i,
-        n,
-        x = transform.invertX(d3.event.x),
-        y = transform.invertY(d3.event.y),
         dx,
         dy;
 
-      for (i = selectedNodes.length - 1; i >= 0; --i) {
-        selectedNode = selectedNodes[i];
-        dx = x - selectedNode.x;
-        dy = y - selectedNode.y;
-        if (dx * dx + dy * dy < radius * radius) {
-          selectedNode.x = transform.applyX(selectedNode.x);
-          selectedNode.y = transform.applyY(selectedNode.y);
-          return selectedNode;
+      for (i = targets.length - 1; i >= 0; --i) {
+        target = targets[i];
+        dx = Math.floor(source.x - target.x);
+        dy = Math.floor(source.y - target.y);
+        if ((dx * dx + dy * dy) < (target.radius * target.radius)) {
+          result = target;
         }
       }
+      return result;
     }
 
-    // function dragged() {
-    //   d3.event.subject.x = transform.invertX(d3.event.x);
-    //   d3.event.subject.y = transform.invertY(d3.event.y);
-    //   draw();
-    // }
+    function mousemove() {
+      d3.select(this).style('cursor', 'default');
+      var node = detectCollision({
+        'x': transform.invertX(d3.event.layerX),
+        'y': transform.invertY(d3.event.layerY)
+      }, nodes);
+      if (node) d3.select(this).style('cursor', 'move');
+    }
+
+    function dragsubject() {
+      var node = detectCollision({
+        'x': transform.invertX(d3.event.x),
+        'y': transform.invertY(d3.event.y)
+      }, nodes);
+      node.x = transform.applyX(node.x);
+      node.y = transform.applyY(node.y);
+
+      return node;
+    }
 
     function dragstarted() {
       if (!d3.event.active) simulation.alphaTarget(0.3).restart();
@@ -156,5 +139,56 @@
       d3.event.subject.fy = null;
     }
 
+    function zoomed() {
+      transform = d3.event.transform;
+      draw();
+    }
   });
+}
+
+// Set a group for each nodes in graph
+function setGroup(graph) {
+  var edges = [],
+    nodes = [];
+  for (var i = 0; i < graph.nodes.length; i++) {
+    nodes.push(i);
+  }
+  for (var i = 0; i < graph.links.length; i++) {
+    var edge = graph.links[i];
+    edge.weight = edge.value;
+    edges.push(edge);
+  }
+
+  // Create the "community"
+  var community = jLouvain().nodes(nodes).edges(edges),
+    res = community();
+
+  // Affect community for each node
+  for (var key in res) {
+    graph.nodes[nodes[key]].group = res[key];
+  }
+
+  return graph;
+}
+
+function getSelectedData(graph, lim) {
+  var deleted_links = {},
+    selectedLinks = graph.links.filter(function(d) {
+      var res = (d.value >= lim);
+      if (!res) {
+        deleted_links[d.source] = deleted_links[d.source] + 1 || 1;
+        deleted_links[d.target] = deleted_links[d.target] + 1 || 1;
+      }
+      return res;
+    }),
+    selectedNodes = graph.nodes.filter(function(d) {
+      d.value = d.value - (deleted_links[d.id] || 0);
+      var res = (d.value > 0);
+      return res;
+    });
+
+  return {
+    'links': selectedLinks,
+    'nodes': selectedNodes
+  };
 }
\ No newline at end of file