From 1486f2fda7ac644a1dabc91ff81b13baef9ff789 Mon Sep 17 00:00:00 2001
From: Wenzel Jakob <wenzel@cs.cornell.edu>
Date: Sat, 10 Aug 2013 20:56:42 +0200
Subject: [PATCH] generic getCorner() and getChild() methods for AABB

---
 include/mitsuba/core/aabb.h | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/include/mitsuba/core/aabb.h b/include/mitsuba/core/aabb.h
index 3e9db7f4..04fd075b 100644
--- a/include/mitsuba/core/aabb.h
+++ b/include/mitsuba/core/aabb.h
@@ -129,6 +129,32 @@ template <typename T> struct TAABB {
 		return (max + min) * (Scalar) 0.5;
 	}
 
+	/// Return the position of one of the corners (in <tt>0..2^dim-1</tt>)
+	inline PointType getCorner(int index) const {
+		PointType result;
+		for (int d=0; d<PointType::dim; ++d) {
+			if (index & (1 << d))
+				result[d] = max[d];
+			else
+				result[d] = min[d];
+		}
+		return result;
+	}
+
+	/// Return a child bounding box in a interval-, quad-, octtree, etc.
+	inline TAABB getChild(int index) const {
+		TAABB result(getCenter());
+
+		for (int d=0; d<PointType::dim; ++d) {
+			if (index & (1 << d))
+				result.max[d] = max[d];
+			else
+				result.min[d] = min[d];
+		}
+
+		return result;
+	}
+
 	/// Check whether a point lies on or inside the bounding box
 	inline bool contains(const PointType &vec) const {
 		for (int i=0; i<PointType::dim; ++i)