--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dwtx/draw2d/graph/RankSorter.d	Sun Aug 03 00:52:14 2008 +0200
@@ -0,0 +1,239 @@
+/*******************************************************************************
+ * Copyright (c) 2003, 2005 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     IBM Corporation - initial API and implementation
+ * Port to the D programming language:
+ *     Frank Benoit <benoit@tionex.de>
+ *******************************************************************************/
+module dwtx.draw2d.graph.RankSorter;
+
+import dwt.dwthelper.utils;
+import dwtx.dwtxhelper.Collection;
+import dwtx.dwtxhelper.Random;
+import dwtx.draw2d.graph.Node;
+import dwtx.draw2d.graph.Rank;
+import dwtx.draw2d.graph.DirectedGraph;
+import dwtx.draw2d.graph.EdgeList;
+import dwtx.draw2d.graph.Edge;
+import dwtx.draw2d.graph.GraphUtilities;
+
+/**
+ * Sorts Ranks during the up and down sweeps of the MinCross visitor.
+ * @author Randy Hudson
+ * @since 2.1.2
+ */
+class RankSorter {
+
+Random flipflop;
+Node node;
+double rankSize, prevRankSize, nextRankSize;
+int currentRow;
+Rank rank;
+double progress;
+DirectedGraph g;
+
+public this(){
+    flipflop = new Random(3);
+}
+
+protected void assignIncomingSortValues() {
+    rankSize = rank.total;
+    prevRankSize = g.ranks.getRank(currentRow - 1).total;
+    if (currentRow < g.ranks.size() - 1)
+        nextRankSize = g.ranks.getRank(currentRow + 1).total;
+    for (int n = 0; n < rank.count(); n++) {
+        node = rank.getNode(n);
+        sortValueIncoming();
+    }
+}
+
+protected void assignOutgoingSortValues() {
+    rankSize = rank.total;
+    prevRankSize = g.ranks.getRank(currentRow + 1).total;
+    if (currentRow > 1)
+        nextRankSize = g.ranks.getRank(currentRow - 1).total;
+
+    for (int n = 0; n < rank.count(); n++) {
+        node = rank.getNode(n);
+        sortValueOutgoing();
+    }
+}
+
+double evaluateNodeIncoming() {
+    bool change = false;
+    EdgeList incoming = node.incoming;
+    do {
+        change = false;
+        for (int i = 0; i < incoming.size() - 1; i++) {
+            if (incoming.getSourceIndex(i) > incoming.getSourceIndex(i + 1)) {
+                Edge e = incoming.getEdge(i);
+                incoming.set(i, incoming.get(i + 1));
+                incoming.set(i + 1, e);
+                change = true;
+            }
+        }
+    } while (change);
+
+    int n = incoming.size();
+    if (n is 0) {
+        return node.index * prevRankSize / rankSize;
+    }
+    if (n % 2 is 1)
+        return incoming.getSourceIndex(n / 2);
+
+    int l = incoming.getSourceIndex(n / 2 - 1);
+    int r = incoming.getSourceIndex(n / 2);
+    if (progress >= 0.8 && n > 2) {
+        int dl = l - incoming.getSourceIndex(0);
+        int dr = incoming.getSourceIndex(n - 1) - r;
+        if (dl < dr)
+            return l;
+        if (dl > dr)
+            return r;
+    }
+    if (progress > 0.25 && progress < 0.75) {
+        if (flipflop.nextBoolean())
+            return (l + l + r) / 3.0;
+        else
+            return (r + r + l) / 3.0;
+    }
+    return (l + r) / 2.0;
+}
+
+double evaluateNodeOutgoing() {
+    bool change = false;
+    EdgeList outgoing = node.outgoing;
+    do {
+        change = false;
+        for (int i = 0; i < outgoing.size() - 1; i++) {
+            if (outgoing.getTargetIndex(i) > outgoing.getTargetIndex(i + 1)) {
+                Edge e = outgoing.getEdge(i);
+                outgoing.set(i, outgoing.get(i + 1));
+                outgoing.set(i + 1, e);
+                change = true;
+            }
+        }
+    } while (change);
+
+    int n = outgoing.size();
+    if (n is 0)
+        return node.index * prevRankSize / rankSize;
+    if (n % 2 is 1)
+        return outgoing.getTargetIndex(n / 2);
+    int l = outgoing.getTargetIndex(n / 2 - 1);
+    int r = outgoing.getTargetIndex(n / 2);
+    if (progress >= 0.8 && n > 2) {
+        int dl = l - outgoing.getTargetIndex(0);
+        int dr = outgoing.getTargetIndex(n - 1) - r;
+        if (dl < dr)
+            return l;
+        if (dl > dr)
+            return r;
+    }
+    if (progress > 0.25 && progress < 0.75) {
+        if (flipflop.nextBoolean())
+            return (l + l + r) / 3.0;
+        else
+            return (r + r + l) / 3.0;
+    }
+    return (l + r) / 2.0;
+}
+
+public void sortRankIncoming(DirectedGraph g, Rank rank, int row, double progress) {
+    this.currentRow = row;
+    this.rank = rank;
+    this.progress = progress;
+    assignIncomingSortValues();
+    sort();
+    postSort();
+}
+
+public void init(DirectedGraph g) {
+    this.g = g;
+    for (int i = 0; i < g.ranks.size(); i++) {
+        rank = g.ranks.getRank(i);
+
+        //Sort the ranks based on their constraints. Constraints are preserved throughout.
+        Collections.sort(rank, new class() Comparator {
+            public int compare(Object left, Object right) {
+                return (cast(Node)left).rowOrder - (cast(Node)right).rowOrder;
+            }
+        });
+        postSort();
+    }
+}
+
+void optimize(DirectedGraph g) {
+}
+
+protected void postSort() {
+    rank.assignIndices();
+}
+
+void sort() {
+    bool change;
+    do {
+        change = false;
+        for (int i = 0; i < rank.size() - 1; i++)
+            change |= swap(i);
+        if (!change)
+            break;
+        change = false;
+        for (int i = rank.size() - 2; i >= 0; i--)
+            change |= swap(i);
+    } while (change);
+}
+
+bool swap(int i) {
+    Node left = rank.getNode(i);
+    Node right = rank.getNode(i + 1);
+    if (GraphUtilities.isConstrained(left, right))
+        return false;
+    if (left.sortValue <= right.sortValue)
+        return false;
+    rank.set(i, right);
+    rank.set(i + 1, left);
+    return true;
+}
+
+public void sortRankOutgoing(DirectedGraph g, Rank rank, int row, double progress) {
+    this.currentRow = row;
+    this.rank = rank;
+    this.progress = progress;
+    assignOutgoingSortValues();
+    sort();
+    postSort();
+}
+
+void sortValueIncoming() {
+    node.sortValue = evaluateNodeIncoming();
+    //$TODO restore this optimization
+//  if (progress is 0.0 && !(node instanceof VirtualNode))
+//      node.sortValue = -1;
+    double value = evaluateNodeOutgoing();
+    if (value < 0)
+        value = node.index * nextRankSize / rankSize;
+    node.sortValue += value * progress;
+//  if (progress < 0.7 && node.sortValue !is -1)
+//      node.sortValue += Math.random() * rankSize / (5 + 8 * progress);
+}
+
+void sortValueOutgoing() {
+    node.sortValue = evaluateNodeOutgoing();
+    //$TODO restore this optimization
+//  if (progress is 0.0 && !(node instanceof VirtualNode))
+//      node.sortValue = -1;
+    double value = evaluateNodeIncoming();
+    if (value < 0)
+        value = node.index * nextRankSize / rankSize;
+    node.sortValue += value * progress;
+//  if (progress < 0.7 && node.sortValue !is -1)
+//      node.sortValue += Math.random() * rankSize / (5 + 8 * progress);
+}
+
+}