Balanced Layout first level approach

mindplot/src/main/javascript/nlayout/BalancedSorter.js

@@ -0,0 +1,175 @@
+mindplot.nlayout.BalancedSorter = new Class({
+    Extends: mindplot.nlayout.ChildrenSorterStrategy,
+
+    initialize: function() {
+
+    },
+
+    computeChildrenIdByHeights: function(treeSet, node) {
+        var result = {};
+        this._computeChildrenHeight(treeSet, node, result);
+        return result;
+    },
+
+    _computeChildrenHeight : function(treeSet, node, heightCache) {
+        var height = node.getSize().height + (mindplot.nlayout.BalancedSorter.INTERNODE_VERTICAL_PADDING * 2); // 2* Top and down padding;
+
+        var result;
+        var children = treeSet.getChildren(node);
+        if (children.length == 0) {
+            result = height;
+        } else {
+            var childrenHeight = 0;
+            children.forEach(function(child) {
+                childrenHeight += this._computeChildrenHeight(treeSet, child, heightCache);
+            }, this);
+
+            result = Math.max(height, childrenHeight);
+        }
+
+        if (heightCache) {
+            heightCache[node.getId()] = result;
+        }
+
+        return result;
+    },
+
+    predict : function(parent, graph, position) {
+
+        // No children...
+        var children = graph.getChildren(parent);
+        if (children.length == 0) {
+            return [0,parent.getPosition()];  // @Todo:Change x ...
+        }
+
+        // Try to fit within ...
+        //
+        // - Order is change if the position top position is changed ...
+        // - Suggested position is the middle between the two topics...
+        //
+        var result = null;
+        children.forEach(function(child) {
+            var cpos = child.getPosition();
+            if (position.y > cpos.y) {
+                result = [child.getOrder(),{x:cpos.x,y:cpos.y + child.getSize().height}];
+            }
+        });
+
+        // Ok, no overlap. Suggest a new order.
+        if (result) {
+            var last = children.getLast();
+            result = [last.getOrder() + 1,{x:cpos.x,y:cpos.y - (mindplot.nlayout.BalancedSorter.INTERNODE_VERTICAL_PADDING * 4)}];
+        }
+
+        return result;
+    },
+
+    insert: function(treeSet, parent, child, order) {
+        var children = this._getSortedChildren(treeSet, parent);
+        $assert(order <= children.length, "Order must be continues and can not have holes. Order:" + order);
+        $assert(order <= children.length, "Order must be continues and can not have holes. Order:" + order);
+
+        // Shift all the elements in one .
+        for (var i = order; i < children.length; i++) {
+            var node = children[i];
+            node.setOrder(i + 1);
+        }
+        child.setOrder(order);
+    },
+
+    detach:function(treeSet, node) {
+        var parent = treeSet.getParent(node);
+        var children = this._getSortedChildren(treeSet, parent);
+        var order = node.getOrder();
+        $assert(children[order] === node, "Node seems not to be in the right position");
+
+        // Shift all the nodes ...
+        for (var i = node.getOrder() + 1; i < children.length; i++) {
+            var child = children[i];
+            child.setOrder(child.getOrder() - 1);
+        }
+        node.setOrder(0);
+    },
+
+    _getSortedChildren:function(treeSet, node) {
+        var result = treeSet.getChildren(node);
+        result.sort(function(a, b) {
+            return a.getOrder() - b.getOrder()
+        });
+        return result;
+    },
+
+    verify:function(treeSet, node) {
+        // Check that all is consistent ...
+        var children = this._getSortedChildren(treeSet, node);
+
+        for (var i = 0; i < children.length; i++) {
+            $assert(children[i].getOrder() == i, "missing order elements");
+        }
+    },
+
+    computeOffsets:function(treeSet, node) {
+        $assert(treeSet, "treeSet can no be null.");
+        $assert(node, "node can no be null.");
+
+        var children = this._getSortedChildren(treeSet, node);
+
+        // Compute heights ...
+        var heights = children.map(function(child) {
+            return {id:child.getId(), order:child.getOrder(), height:this._computeChildrenHeight(treeSet, child)};
+        }, this);
+
+
+        // Compute the center of the branch ...
+        var totalPHeight = 0;
+        var totalNHeight = 0;
+        //TODO(gb): optimize using filter
+        heights.forEach(function(elem) {
+            if (elem.order % 2 == 0) {
+                totalPHeight += elem.height;
+            } else {
+                totalNHeight += elem.height;
+            }
+        });
+        var psum = totalPHeight/2;
+        var nsum = totalNHeight/2;
+        var totalDifference = totalPHeight - totalNHeight;
+        var ysum = 0;
+
+        // Calculate the offsets ...
+        var result = {};
+        for (var i = 0; i < heights.length; i++) {
+            var direction = heights[i].order % 2 ? -1 : 1;
+
+            if (direction > 0) {
+                psum = psum - heights[i].height;
+                ysum = psum;
+            } else {
+                nsum = nsum - heights[i].height;
+                ysum = nsum;
+            }
+
+//            console.log("node {id: " + heights[i].id + ", order: " + heights[i].order + ", psum: " + psum + ", nsum: " + nsum + "}");        //TODO(gb): Remove trace!!!
+//            console.log("totalPHeight: " + totalPHeight + ", totalNHeight: " + totalNHeight);        //TODO(gb): Remove trace!!!
+            console.log("node {id: " + heights[i].id + ", totalDifference: " + totalDifference + ", direction: " + direction + "}");        //TODO(gb): Remove trace!!!
+
+            var yOffset = ysum + heights[i].height/2;
+            var xOffset = direction * (node.getSize().width + mindplot.nlayout.SymetricSorter.INTERNODE_HORIZONTAL_PADDING);
+
+            $assert(!isNaN(xOffset), "xOffset can not be null");
+            $assert(!isNaN(yOffset), "yOffset can not be null");
+
+            result[heights[i].id] = {x:xOffset,y:yOffset};
+        }
+        console.log("----------------------\n");        //TODO(gb): Remove trace!!!
+        return result;
+    },
+
+    toString:function() {
+        return "Balanced Sorter";
+    }
+});
+
+mindplot.nlayout.BalancedSorter.INTERNODE_VERTICAL_PADDING = 5;
+mindplot.nlayout.BalancedSorter.INTERNODE_HORIZONTAL_PADDING = 5;
+mindplot.nlayout.BalancedSorter.INITIAL_HEIGHT = 100;