--- a/include/kdtree.h	Tue Apr 22 13:33:12 2008 +0200
+++ b/include/kdtree.h	Wed Apr 23 10:38:33 2008 +0200
@@ -53,19 +53,19 @@
 	~KdNode();
 
 	void setLeaf() { flags |= 3; };
-	bool isLeaf() { return (flags & 3) == 3; };
+	const bool isLeaf() const { return (flags & 3) == 3; };
 
 	void setAxis(int aAxis) { flags &= ~3; flags |= aAxis; };
-	short getAxis() { return flags & 3; };
+	const int getAxis() const { return flags & 3; };
 
 	void setSplit(Float aSplit) { split = aSplit; };
-	Float& getSplit() { return split; };
+	const Float& getSplit() const { return split; };
 
 	void setChildren(KdNode *node) { children = node; assert((flags & 3) == 0); };
-	KdNode* getLeftChild() { return (KdNode*)((off_t)children & ~3); };
-	KdNode* getRightChild() { return (KdNode*)((off_t)children & ~3) + 1; };
+	KdNode* getLeftChild() const { return (KdNode*)((off_t)children & ~3); };
+	KdNode* getRightChild() const { return (KdNode*)((off_t)children & ~3) + 1; };
 
-	ShapeList* getShapes() { return (ShapeList*)((off_t)shapes & ~3); };
+	ShapeList* getShapes() const { return (ShapeList*)((off_t)shapes & ~3); };
 	void addShape(Shape* aShape) { getShapes()->push_back(aShape); };
 };
 
@@ -79,6 +79,7 @@
 	int max_depth;
 
 	void recursive_build(KdNode *node, BBox bbox, int maxdepth);
+	void recursive_load(istream &st, KdNode *node);
 public:
 	KdTree() : Container(), root(NULL), built(false), max_depth(32) {};
 	~KdTree() { if (root) delete root; };
@@ -87,9 +88,12 @@
 		Float &nearest_distance);
 	void optimize() { build(); };
 	void build();
-	void save(ostream &str, KdNode *node = NULL);
-	void load(istream &str, KdNode *node = NULL);
+	const bool isBuilt() const { return built; };
+	KdNode *getRootNode() const { return root; };
 	void setMaxDepth(int md) { max_depth = md; };
+
+	ostream & dump(ostream &st);
+	istream & load(istream &st);
 };
 
 #endif