diff --git a/data/scripts/rendertime.py b/data/scripts/rendertime.py
new file mode 100644
index 00000000..46f7012d
--- /dev/null
+++ b/data/scripts/rendertime.py
@@ -0,0 +1,37 @@
+import subprocess, sys, re
+
+if len(sys.argv) == 1:
+    print('rendertime.py: Simple utility to extract the rendering time of an EXR file created using Mitsuba')
+    print('Syntax: rendertime.py <one or more EXR files>')
+
+for arg in sys.argv[1:]:
+    sys.stdout.write("%s: " % arg)
+
+    p = subprocess.Popen(["exrheader", arg], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+    matches = re.findall('Render time: ([^\n]*)', p.communicate()[0])
+    if len(matches) != 1:
+        sys.stdout.write('error reading metadata!\n')
+        continue
+
+    value = matches[0]
+
+    units = [
+        ['d', 60*60*24],
+        ['h', 60*60],
+        ['m', 60],
+        ['s', 1]
+    ];
+
+    for unit in units:
+        if value[-1] == unit[0]:
+            value = float(value[0:-1]) * unit[1]
+            break
+
+    force = False
+    for unit in units:
+        if value > unit[1] or force:
+            amount = int(value / unit[1])
+            value -= amount * unit[1]
+            force = True
+            sys.stdout.write('%i%s ' % (amount, unit[0]))
+    sys.stdout.write('\n')
diff --git a/include/mitsuba/render/gkdtree.h b/include/mitsuba/render/gkdtree.h
index 416caedb..53129d66 100644
--- a/include/mitsuba/render/gkdtree.h
+++ b/include/mitsuba/render/gkdtree.h
@@ -30,7 +30,7 @@
 #endif
 
 /// Activate lots of extra checks
-// #define MTS_KD_DEBUG 1
+#define MTS_KD_DEBUG 1
 
 /** Compile-time KD-tree depth limit. Allows to put certain
     data structures on the stack */
@@ -2449,9 +2449,9 @@ protected:
 			for (SizeType i=0; i<m_primCount; ++i) {
 				const AABBType aabb = derived->getAABB(indices[i]);
 				for (int axis=0; axis<PointType::dim; ++axis) {
-					int64_t minIdx = (int64_t) ((aabb.min[axis] - m_aabb.min[axis])
+					int64_t minIdx = (int64_t) (((float) aabb.min[axis] - (float) m_aabb.min[axis])
 							* m_invBinSize[axis]);
-					int64_t maxIdx = (int64_t) ((aabb.max[axis] - m_aabb.min[axis])
+					int64_t maxIdx = (int64_t) (((float) aabb.max[axis] - (float) m_aabb.min[axis])
 							* m_invBinSize[axis]);
 					m_maxBins[axis * m_binCount
 						+ std::max((int64_t) 0, std::min(maxIdx, maxBin))]++;
diff --git a/src/sensors/SConscript b/src/sensors/SConscript
index f2279584..4795c2dd 100644
--- a/src/sensors/SConscript
+++ b/src/sensors/SConscript
@@ -9,5 +9,6 @@ plugins += env.SharedLibrary('thinlens', ['thinlens.cpp'])
 plugins += env.SharedLibrary('orthographic', ['orthographic.cpp'])
 plugins += env.SharedLibrary('telecentric', ['telecentric.cpp'])
 plugins += env.SharedLibrary('spherical', ['spherical.cpp'])
+plugins += env.SharedLibrary('fisheye', ['fisheye.cpp'])
 
 Export('plugins')