From c866cda90cb98768d03ae928ad75ae0d74f37ca2 Mon Sep 17 00:00:00 2001
From: Anya <anyazhang01@yahoo.com>
Date: Fri, 28 Jun 2019 11:59:13 +0200
Subject: [PATCH] Allow manual ranking

---
 lib/layout.js     | 2 +-
 lib/rank/index.js | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/layout.js b/lib/layout.js
index 26b07304..e68d8e79 100644
--- a/lib/layout.js
+++ b/lib/layout.js
@@ -97,7 +97,7 @@ function updateInputGraph(inputGraph, layoutGraph) {
 var graphNumAttrs = ["nodesep", "edgesep", "ranksep", "marginx", "marginy"];
 var graphDefaults = { ranksep: 50, edgesep: 20, nodesep: 50, rankdir: "tb" };
 var graphAttrs = ["acyclicer", "ranker", "rankdir", "align"];
-var nodeNumAttrs = ["width", "height"];
+var nodeNumAttrs = ["width", "height", "rank"];
 var nodeDefaults = { width: 0, height: 0 };
 var edgeNumAttrs = ["minlen", "weight", "width", "height", "labeloffset"];
 var edgeDefaults = {
diff --git a/lib/rank/index.js b/lib/rank/index.js
index 5ec26c8d..b24a0774 100644
--- a/lib/rank/index.js
+++ b/lib/rank/index.js
@@ -27,10 +27,16 @@ module.exports = rank;
  *       fix them up later.
  */
 function rank(g) {
+  var ranker = g.graph().ranker;
+  if (ranker instanceof Function) {
+    return ranker(g)
+  }
+
   switch(g.graph().ranker) {
   case "network-simplex": networkSimplexRanker(g); break;
   case "tight-tree": tightTreeRanker(g); break;
   case "longest-path": longestPathRanker(g); break;
+  case "none": break;
   default: networkSimplexRanker(g);
   }
 }