[turbolizer] Redetermine graph bounding box after dragging a node.

tools/turbolizer/graph-layout.js

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 var DEFAULT_NODE_ROW_SEPARATION = 130
 
 var traceLayout = false;
 
 function newGraphOccupation(graph){
   var isSlotFilled = [];
@@ skipping 229 matching lines @@
           s += " ";
         }
       }
       console.log(s);
     }
   }
   return occupation;
 }
 
 function layoutNodeGraph(graph) {
-  graph.minGraphX = 0;
-  graph.maxGraphNodeX = 1;
-  graph.maxGraphX = 1;
-  graph.minGraphY = 0;
-  graph.maxGraphY = 1;
-
   // First determine the set of nodes that have no outputs. Those are the
   // basis for bottom-up DFS to determine rank and node placement.
   var endNodesHasNoOutputs = [];
   var startNodesHasNoInputs = [];
   graph.nodes.forEach(function(n, i){
     endNodesHasNoOutputs[n.id] = true;
     startNodesHasNoInputs[n.id] = true;
   });
   graph.edges.forEach(function(e, i){
     endNodesHasNoOutputs[e.source.id] = false;
@@ skipping 149 matching lines @@
         nodeToPlace.x = occupation.occupyNode(nodeToPlace);
         if (traceLayout) {
           console.log("Node " + nodeToPlace.id + " is placed between [" + nodeToPlace.x + ", " + (nodeToPlace.x + nodeToPlace.getTotalNodeWidth()) + ")");
         }
         var staggeredFlooredI = Math.floor(placedCount++ % 3);
         var delta = MINIMUM_EDGE_SEPARATION * staggeredFlooredI
         nodeToPlace.outputApproach += delta;
       } else {
         nodeToPlace.x = 0;
       }
-
-      if (nodeToPlace.x < graph.minGraphX) {
-        graph.minGraphX = nodeToPlace.x;
-      }
-      if ((nodeToPlace.y - 50) < graph.minGraphY) {
-        graph.minGraphY = nodeToPlace.y - 50;
-      }
-      if ((nodeToPlace.x + nodeToPlace.getTotalNodeWidth()) > graph.maxGraphNodeX) {
-        graph.maxGraphNodeX = nodeToPlace.x + nodeToPlace.getTotalNodeWidth();
-      }
-      if ((nodeToPlace.y + graph.getNodeHeight() + 50) > graph.maxGraphY) {
-        graph.maxGraphY = nodeToPlace.y + graph.getNodeHeight() + 50;
-      }
     }
 
     if (traceLayout) {
       console.log("Before clearing nodes");
       occupation.print();
     }
 
     occupation.clearOccupiedNodes();
 
     if (traceLayout) {
       console.log("After clearing nodes");
       occupation.print();
     }
 
     for (var i = 0; i < rankSet.length; ++i) {
       var node = rankSet[i];
       occupation.occupyNodeInputs(node);
     }
 
     if (traceLayout) {
       console.log("After occupying inputs");
       occupation.print();
     }
+
+    if (traceLayout) {
+      console.log("After determining bounding box");
+      occupation.print();
+    }
   });
 
-  var backEdgeNumber = 0;
+  graph.maxBackEdgeNumber = 0;
   graph.visibleEdges.each(function (e) {
     if (e.isBackEdge()) {
-      e.backEdgeNumber = ++backEdgeNumber;
+      e.backEdgeNumber = ++graph.maxBackEdgeNumber;
     } else {
       e.backEdgeNumber = 0;
     }
   });
 
+  redetermineGraphBoundingBox(graph);
+
+}
+
+function redetermineGraphBoundingBox(graph) {
+  graph.minGraphX = 0;
+  graph.maxGraphNodeX = 1;
+  graph.maxGraphX = undefined;  // see below
+  graph.minGraphY = 0;
+  graph.maxGraphY = 1;
+
+  for (var i = 0; i < graph.nodes.length; ++i) {
+    var node = graph.nodes[i];
+
+    if (!node.visible) {
+      continue;
+    }
+
+    if (node.x < graph.minGraphX) {
+      graph.minGraphX = node.x;
+    }
+    if ((node.x + node.getTotalNodeWidth()) > graph.maxGraphNodeX) {
+      graph.maxGraphNodeX = node.x + node.getTotalNodeWidth();
+    }
+    if ((node.y - 50) < graph.minGraphY) {
+      graph.minGraphY = node.y - 50;
+    }
+    if ((node.y + graph.getNodeHeight() + 50) > graph.maxGraphY) {
+      graph.maxGraphY = node.y + graph.getNodeHeight() + 50;
+    }
+  }
+
   graph.maxGraphX = graph.maxGraphNodeX +
-    backEdgeNumber * MINIMUM_EDGE_SEPARATION;
+    graph.maxBackEdgeNumber * MINIMUM_EDGE_SEPARATION;
+
 }