New classes: Link and GraphViewer (TORO graph visualization and laser scans occupancy grid)

New parameter: RGBD/ToroIterations=100
Rtabmap: added getGraph() method to get TORO poses/link constraints
Fixed ICP correspondences ratio over 1
CloudViewer: added frustum culling and camera view up z lock in render(), moving camera using arrow keys, Menu options: Camera far plane clipping, background color
DatabaseViewer: added 3D Map view and Graph view
MainWindow: Moved main widget (loop closure image status) to a dock widget, added Graph view.


git-svn-id: http://rtabmap.googlecode.com/svn/trunk/rtabmap@1075 f169173b-cf89-36c8-b27e-44dbe73f0c83

corelib/include/rtabmap/core/Link.h

@@ -0,0 +1,42 @@
+/*
+ * Link.h
+ *
+ *  Created on: 2014-01-29
+ *      Author: mathieu
+ */
+
+#ifndef LINK_H_
+#define LINK_H_
+
+#include <rtabmap/core/Transform.h>
+
+namespace rtabmap {
+
+class Link
+{
+public:
+	enum Type {kNeighbor, kGlobalClosure, kLocalSpaceClosure, kLocalTimeClosure};
+	Link(int from, int to, const Transform & transform, Type type) :
+		from_(from),
+		to_(to),
+		transform_(transform),
+		type_(type)
+	{
+	}
+
+	int from() const {return from_;}
+	int to() const {return to_;}
+	const Transform & transform() const {return transform_;}
+	Type type() const {return type_;}
+
+private:
+	int from_;
+	int to_;
+	Transform transform_;
+	Type type_;
+};
+
+}
+
+
+#endif /* LINK_H_ */