worked on 2D/3D raytracing

adjusted BVH
improved 2D/3D BVH
new bounding volumes
new test cases
renamed some test-cases for grouping reasons
made GPC header-only using slight adjustments

geo/BBox2.h

@@ -1,8 +1,9 @@
-#ifndef BBOX2_H
-#define BBOX2_H
+#ifndef GEO_BBOX2_H
+#define GEO_BBOX2_H
 
 #include "Point2.h"
 #include "Line2.h"
+#include <vector>
 
 class BBox2 {
 
@@ -105,6 +106,21 @@ public:
 		p2 += Point2(val, val);	// increase maximum
 	}
 
+	/** grow the bbox by the amount given for each dimension */
+	void growRel(const float val) {
+		const Point2 center = (p1+p2)/2;
+		p1 += (p1-center)*val;	// decrease minimum
+		p2 += (p2-center)*val;	// increase maximum
+	}
+
+
+	/** combine two bboxes */
+	static BBox2 join(const BBox2& bb1, const BBox2& bb2) {
+		const Point2 min( std::min(bb1.p1.x, bb2.p1.x), std::min(bb1.p1.y, bb2.p1.y) );
+		const Point2 max( std::max(bb1.p2.x, bb2.p2.x), std::max(bb1.p2.y, bb2.p2.y) );
+		return BBox2(min, max);
+	}
+
 };
 
-#endif // BBOX2_H
+#endif // GEO_BBOX2_H