--- ray/doc/notes/ReleaseNotes	2021/02/12 01:04:39	1.383
+++ ray/doc/notes/ReleaseNotes	2021/03/27 17:50:18	1.389
@@ -2412,3 +2412,20 @@ from Peter Apian-Bennewitz.
 Added explicit tests for on-edge intersections with polygons.  This should
 eliminate stray rays and tiny light leaks that often appear even in
 well-constructed geometry.
+
+Added "-s up" option to pabopto2bsdf to allow for 180 degree symmetry,
+meaning that data repeats after 180 degree rotation (as distinguished
+from "-s bilateral" whose data is mirrored about a vertical plane).
+Thanks to Helen Rose Wilson for the suggestion and informing me that
+such a thing exists.
+
+Removed upper limit on number of modifiers in rcontrib.
+
+Put cap on maximum ambient gradient to avoid over-extrapolation of
+poorly computed irradiance cache values.
+
+Added robjutil +T option to triangulate all faces in .OBJ description.
+
+Altered BSDF library to have both front and back diffuse transmittance
+values, which can be different.  This was necessary to avoid issues
+caused by measurement and modeling discrepancies.