diff -r d8d596d26f25 -r bf17f9f84c91 src/kdtree.cc
--- a/src/kdtree.cc	Sun Nov 18 11:20:56 2007 +0100
+++ b/src/kdtree.cc	Thu Nov 22 17:53:34 2007 +0100
@@ -1,36 +1,129 @@
-#include "kdtree.cc"
+#include <algorithm>
+
+#include "kdtree.h"
 
-void KdTree::KdTree(ShapeList &shapelist):
+void Container::addShape(Shape* aShape)
+{
+	shapes.push_back(aShape);
+	if (shapes.size() == 0) {
+		/* initialize bounding box */
+		bbox = aShape->get_bbox();
+	} else {
+		/* adjust bounding box */
+		BBox shapebb = aShape->get_bbox();
+		if (shapebb.L.x < bbox.L.x)  bbox.L.x = shapebb.L.x;
+		if (shapebb.L.y < bbox.L.y)  bbox.L.y = shapebb.L.y;
+		if (shapebb.L.z < bbox.L.z)  bbox.L.z = shapebb.L.z;
+		if (shapebb.R.x > bbox.R.x)  bbox.R.x = shapebb.R.x;
+		if (shapebb.R.y > bbox.R.y)  bbox.R.y = shapebb.R.y;
+		if (shapebb.R.z > bbox.R.z)  bbox.R.z = shapebb.R.z;
+	}
+};
+
+void KdNode::subdivide(BBox bbox, int depth, int count)
 {
-	root = new KdNode();
-	shapes = new vector<Shape*>();
+	int axis;
+	float pos;
+
+	//if (stopcriterionmet()) return
+
+	// choose split axis
+	axis = 0;
+	if (bbox.R.y - bbox.L.y > bbox.R.x - bbox.L.x)
+		axis = 1;
+	if (bbox.R.z - bbox.L.z > bbox.R.y - bbox.L.y)
+		axis = 2;
+
+	// *** find optimal split position
+	SortableShapeList sslist(shapes, axis);
+	sort(sslist.begin(), sslist.end());
+
+	SplitList splitlist = SplitList();
+
+	SortableShapeList::iterator sh;
+	for (sh = sslist.begin(); sh != sslist.end(); sh++)
+	{
+		splitlist.push_back(SplitPos(sh->bbox.L.cell[axis]));
+		splitlist.push_back(SplitPos(sh->bbox.R.cell[axis]));
+	}
+	sort(splitlist.begin(), splitlist.end());
+
+	// find all posible splits
+	SplitList::iterator split;
+	int rest;
+	for (split = splitlist.begin(); split != splitlist.end(); split++)
+	{
+		for (sh = sslist.begin(), rest = sslist.size(); sh != sslist.end(); sh++, rest--)
+		{
+			if (sh->hasMark())
+				continue;
+			// if shape is on left side of split plane
+			if (sh->bbox.R.cell[axis] <= split->pos)
+			{
+				sh->setMark();
+				split->lnum++;
+			}
+			// if shape is completely contained in split plane
+			if (sh->bbox.L.cell[axis] == sh->bbox.R.cell[axis] == split->pos)
+			{
+				if (split->pos - bbox.L.cell[axis] < bbox.R.cell[axis] - split->pos)
+				{
+					// left subcell is smaller -> if not empty, put shape here
+					if (split->lnum)
+						split->lnum++;
+					else
+						split->rnum++;
+				} else {
+					// right subcell is smaller
+					if (split->rnum)
+						split->rnum++;
+					else
+						split->lnum++;
+				}
+			}
+			// if shape is on right side of split plane
+			if (sh->bbox.L.cell[axis] >= split->pos)
+			{
+				split->rnum += rest;
+				break;
+			}
+			// if shape occupies both sides of split plane
+			if (sh->bbox.L.cell[axis] < split->pos && sh->bbox.R.cell[axis] > split->pos)
+			{
+				split->lnum++;
+				split->rnum++;
+			}
+		}
+	}
+
+	// choose best split pos
+	// ... //
+
+	KdNode *children = new KdNode[2];
+
 	ShapeList::iterator shape;
-	for (shape = shapelist.begin(); shape != shapes.end(); shape++)
-		addShape(*shape);
+	for (shape = shapes.begin(); shape != shapes.end(); shape++)
+	{
+		if (((Triangle*)*shape)->A.cell[axis-1] < pos
+		|| ((Triangle*)*shape)->B.cell[axis-1] < pos
+		|| ((Triangle*)*shape)->C.cell[axis-1] < pos)
+			children[0].addShape(*shape);
+		if (((Triangle*)*shape)->A.cell[axis-1] >= pos
+		|| ((Triangle*)*shape)->B.cell[axis-1] >= pos
+		|| ((Triangle*)*shape)->C.cell[axis-1] >= pos)
+			children[1].addShape(*shape);
+	}
 
-	rebuild();
+	bbox.R[axis-1] = pos;
+	children[0].subdivide(bbox, depth+1, children[0].shapes.size());
+
+	bbox.L[axis-1] = pos;
+	children[1].subdivide(bbox, depth+1, children[1].shapes.size());
 }
 
-void KdTree::Subdivide(KdNode* node, AABB& bbox, int depth, int count)
+void KdTree::build()
 {
-	
-	/*if (stopcriterionmet()) return
-	splitpos = findoptimalsplitposition()
-	leftnode = new Node()
-	rightnode = new Node()
-	for (all primitives in node)
-	{
-		if (node->intersectleftnode()) leftnode->addprimitive( primitive )
-		if (node->intersectrightnode()) rightnode->addprimitive( primitive )
-	}
-	buildkdtree( leftnode )
-		buildkdtree( rightnode )*/
+	root = new KdNode();
+	root->shapes = shapes;
+	root->subdivide(bbox, 0, shapes.size());
 }
-
-void KdTree::rebuild()
-{
-	int count = shapes->size();
-	AABB bbox = shapes->extends();
-
-	Subdivide(root, bbox, 0, count);
-}
\ No newline at end of file