--- ray/doc/notes/ReleaseNotes	2023/11/27 22:04:45	1.433
+++ ray/doc/notes/ReleaseNotes	2023/12/09 23:46:51	1.437
@@ -2634,5 +2634,28 @@ that made reds into blues and vice versa, which has be
 Added i/o for spectral pictures to rmtxop, the first program that can
 ingest them.  (Only rtrace, rcontrib, and rfluxmtx can render them.)
 New symbolic rmtxop -c options, such as RGB, XYZ, S (for scotopic)
-and M (for melanopic) make color conversions simpler.
-Also added spectral picture support to rcrop and radcompare.
+and M (for melanopic) make color conversions simpler.  Alternatively,
+a reference matrix or picture may be given and the color space of
+that file will be used.  The -C option takes either a symbolic
+color space or reference file and is "sticky," so it applies to
+all subsequent input files that do not have their own -c right ahead
+of them.
+
+Added spectral picture support to rcrop and radcompare.
+
+Added new utility, rmtxcomb, which is hard to type and hard to
+pronounce, and probably equally difficult to use.  Sort of a
+combination of rmtxop and pcomb, it works with all the inputs and
+outputs that rmtxop handles, but allows for general expressions
+like those in pcomb for putting matrices together, working on
+an element at a time.  (No resizing of matrices or accessing
+neighboring elements, as permitted in pcomb.)  It saves memory
+over rmtxop by operating on a row at a time, so can handle
+input and output matrices with any number of rows.  It does
+provide for a single matrix-multiplication operation at the end,
+which only requires memory for that final matrix.
+
+Added support for filtering hyperspectral images to pfilt.
+
+Added support for 1- and 3-component float matrix i/o to
+pcomb to allow for better interoperability.