Fix broken positionX shift with multiple classes

dagrejs · Nov 2, 2014 · ad2cf7a · ad2cf7a
1 parent 5ef0dcd
commit ad2cf7a
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Showing 2 changed files with 34 additions and 3 deletions.
diff --git a/lib/position/bk.js b/lib/position/bk.js
@@ -207,6 +207,7 @@ function horizontalCompaction(g, layering, root, align, reverseSep) {
   // We use local variables for these parameters instead of manipulating the
   // graph because it becomes more verbose to access them in a chained manner.
   var shift = {},
+      shiftNeighbor = {},
       sink = {},
       xs = {},
       pred = {},
@@ -223,7 +224,7 @@ function horizontalCompaction(g, layering, root, align, reverseSep) {
 
   _.each(g.nodes(), function(v) {
     if (root[v] === v) {
-      placeBlock(g, layering, sepFn, root, align, shift, sink, pred, xs, v);
+      placeBlock(g, layering, sepFn, root, align, shift, shiftNeighbor, sink, pred, xs, v);
     }
   });
 
@@ -234,14 +235,20 @@ function horizontalCompaction(g, layering, root, align, reverseSep) {
       // http://www.inf.uni-konstanz.de/~brandes/publications/ for details.
       if (v === root[v] && shift[sink[root[v]]] < Number.POSITIVE_INFINITY) {
         xs[v] += shift[sink[root[v]]];
+
+        // Cascade shifts as necessary
+        var w = shiftNeighbor[sink[root[v]]];
+        if (w && shift[w] !== Number.POSITIVE_INFINITY) {
+          xs[v] += shift[w];
+        }
       }
     });
   });
 
   return xs;
 }
 
-function placeBlock(g, layering, sepFn, root, align, shift, sink, pred, xs, v) {
+function placeBlock(g, layering, sepFn, root, align, shift, shiftNeighbor, sink, pred, xs, v) {
   if (_.has(xs, v)) return;
   xs[v] = 0;
 
@@ -250,14 +257,15 @@ function placeBlock(g, layering, sepFn, root, align, shift, sink, pred, xs, v) {
   do {
     if (pred[w]) {
       u = root[pred[w]];
-      placeBlock(g, layering, sepFn, root, align, shift, sink, pred, xs, u);
+      placeBlock(g, layering, sepFn, root, align, shift, shiftNeighbor, sink, pred, xs, u);
       if (sink[v] === v) {
         sink[v] = sink[u];
       }
 
       var delta = sepFn(g, w, pred[w]);
       if (sink[v] !== sink[u]) {
         shift[sink[u]] = Math.min(shift[sink[u]], xs[v] - xs[u] - delta);
+        shiftNeighbor[sink[u]] = sink[v];
       } else {
         xs[v] = Math.max(xs[v], xs[u] + delta);
       }

diff --git a/test/position/bk-test.js b/test/position/bk-test.js
@@ -416,6 +416,29 @@ describe("position/bk", function() {
       expect(xs.d).to.equal(60 / 2 + 75 + 150 / 2);
     });
 
+    it("cascades class shift", function() {
+      var root =  { a: "a", b: "b", c: "c", d: "d", e: "b", f: "f", g: "d" },
+          align = { a: "a", b: "e", c: "c", d: "g", e: "b", f: "f", g: "d" };
+      g.graph().nodesep = 75;
+      g.setNode("a", { rank: 0, order: 0, width: 50 });
+      g.setNode("b", { rank: 0, order: 1, width: 50 });
+      g.setNode("c", { rank: 1, order: 0, width: 50 });
+      g.setNode("d", { rank: 1, order: 1, width: 50 });
+      g.setNode("e", { rank: 1, order: 2, width: 50 });
+      g.setNode("f", { rank: 2, order: 0, width: 50 });
+      g.setNode("g", { rank: 2, order: 1, width: 50 });
+
+      var xs = horizontalCompaction(g, buildLayerMatrix(g), root, align);
+
+      // Use f as 0, everything is relative to it
+      expect(xs.a).to.equal(xs.b - 50 / 2 - 75 - 50 / 2);
+      expect(xs.b).to.equal(xs.e);
+      expect(xs.c).to.equal(xs.f);
+      expect(xs.d).to.equal(xs.c + 50 / 2 + 75 + 50 / 2);
+      expect(xs.e).to.equal(xs.d + 50 / 2 + 75 + 50 / 2);
+      expect(xs.g).to.equal(xs.f + 50 / 2 + 75 + 50 / 2);
+    });
+
     it("handles labelpos = l", function() {
       var root =  { a: "a", b: "b", c: "c" },
           align = { a: "a", b: "b", c: "c" };