--- ray/doc/notes/ReleaseNotes	2017/08/11 21:39:52	1.300
+++ ray/doc/notes/ReleaseNotes	2021/04/07 21:13:52	1.391
@@ -2058,7 +2058,7 @@ Fixed early exit of rcontrib with internal error (samp
 discovered by Rob G.
 
 =================================
-Version 5.1
+Version 5.1 (Released 8/17/2017)
 
 Fixed issue with vchars.mta and symbols.mta not being installed in
 the appropriate metafile library location, with help from Rob G.
@@ -2155,3 +2155,282 @@ which looked to be too difficult from an implementatio
 
 Added bsdfview tool analogous to objview but for BSDF files (XML and SIR),
 which calls bsdf2rad then rad with a few useful default views.
+
+=========================
+Version 5.2 (Release October 8, 2018)
+
+Created psketch program to apply non-photorealistic rendering to selected
+objects, identified by modifier name(s).
+
+Added '*' and '/' operations to rmtxop for element-wise multiplication and
+division of same-sized matrices.
+
+Changed falsecolor so "-s" option is adjusted to match legend if one.
+
+Falsecolor legend changes and improvements by David G-M and Stephen W.
+
+Fixed bug in peak extraction code that generated
+"Bad call to SDqueryTreProjSA" error, reported by Lars Grobe.
+
+Increased maximum luminance to 10^7 in pcond to fix issue noticed
+by Axel Jacobs where veiling glare not added for the sun under
+some conditions.
+
+Increased maximum number of open files in rcontrib to the system upper
+limit of 2048 rather than the default 512 under Windows.
+
+Added top-level resources directory with files from Rob Guglielmetti.
+
+Improved accuracy for peaky BSDFs and small light sources.
+
+Fixed issue with pmapdump noted by Axel Jacobs.
+
+Improved accuracy of bsdf2ttree when converting scattering interpolation
+representatons with strong peaks.
+
+Tweaked peak-extraction code to work more reliably.
+
+Georg Mischler updated SCons build system.
+
+Rob Guglielmetti and Alex Swindler updated CMake build system.
+
+Modified pcomb so the first view seen in the inputs is written into header.
+
+Wrote rtpict script to run rtrace in parallel mode and simulate rpict with
+-n option.
+
+Added ability to move forwards/backwards specified distance in rvu "origin"
+command.  Feature requested by John Mardaljevic, who essentially owns this
+command, now.
+
+Reduced bias in ambient super-sampling method.
+
+Fixed bugs associated with zero transmission in chromatic tensor trees.
+Thanks to Lars Grobe for pointing out issues.
+
+Added RAYPATH searching for -f options to genrev, gensurf, genworm,
+bsdf2klems, bsdf2ttree, and pcomb.  This makes behavior consistent
+with rcalc, calc, and rendering tools.
+
+Worked with Randolph Fritz to fix some issues with ies2rad and newer
+IESNA63 standards.
+
+Resurrected original bsdf2rad test program, renaming it bsdf2rado. Still an
+optional build in src/cv/.
+
+Fixed bug in rcontrib with virtual sources, where pretest was adding
+to modifier accumulation buffers.  Reported by Mostapha.
+
+Added an "aBSDF" material type that explicitly checks for peak extraction.
+Its arguments are the same as the original "BSDF" type, but without the
+thickness parameter, as proxy geometry is not supported by this new type.
+The old "BSDF" type no longer does peak extraction under any circumstances,
+since this behavior is superfluous for proxied geometry.
+
+Added -r option to bsdf2rad (and bsdfview) to fix BSDF min and max range
+for comparing BSDFs.
+
+Fixed issue with pfilt -m option and uneven image size changes pointed
+out by Rob Shakespeare.
+
+Updates to evalglare and gendaylit from Jan Wienold, including new
+colored sky option.
+
+=========================
+Version 5.3 (Released September 1, 2020)
+
+Created radcompare program to compare Radiance tool output to reference outputs
+during unit-testing.
+
+Fixed issue reading very large files (> 2 GBytes) in rcollate.
+
+Made picking function in rvu ignore transparent and void surfaces.
+
+Added -orRxX options to rtrace to enable output of mirrored and unmirrored
+contributions and distances to enable new types of reprojections.  This also
+cleaned up and unified handling of effective ray lengths throughout code.
+
+Bug fixes from Jan Wienold for evalglare.
+
+Changed indexed (numbered) output from dctimestep to start from 0 rather
+than 1, to make it more consistent with expected input naming.
+
+Increased default sampling in bsdf2klems (-n option) to 1024.
+
+Fixed an issue noticed by David G-M that was causing genBSDF to bias
+isotropic tensor tree samples resulting in subsequent failure of
+peak extraction with "aBSDF" type.
+
+Introduced max() and min() functions to .cal library.
+
+Added random incident patch sampling to bsdf2klems to improve accuracy
+with scattering interpolation representation input (e.g., from
+pabopto2bsdf).  The other input types already sampled incident patch area.
+
+Added gendaymtx -A option to compute average sky over all the input
+time steps.
+
+Added ability to output color image from rtrace with any of -ovrx options.
+Also fixed inconsistency of -oN output when ray casting versus full trace.
+Before, it would flip normal to front side unless ray casting.  Now, -oN
+always reports the unflipped normal.
+
+Changed rlam behavior so -iaN reads N lines from a stream rather than N
+characters.  This seems more useful, since -ibN is somewhat redundant with
+the old behavior.
+
+Created rsplit program as compliment to rlam and to handle more complex
+rtrace output into separate files or streams.
+
+Improved getinfo so that it can also hop over resolution string with -c
+and header elide mode.  Use +d to include resolution string in output,
+and -d to elide with - and -c options.
+
+Made pvalue -u option mean "uncompressed" with -r.  Also, allow skipping
+bytes on standard input.
+
+Created rcode_depth tool to convert to and from a 16-bit/pixel portable
+depth image encoding that uses a mix of linear and reciprocal distance
+with explicit representations of 0 and infinity.  Code for loading these
+depth maps is in src/common/depthcodec.{h,c}.
+
+Created rcode_norm tool to convert to and from 32-bit/pixel portable
+surface normal representation, matching the one in src/common/dircode.c.
+Code for loading normal maps is in src/common/normcodec.{h,c}.
+
+Created rcode_ident tool to create indexed identifier files.
+Code for loading these files is in src/common/idmap.{h,c}.
+
+Added -o* option to rtpict to produce layered images that handle most
+output types from rtrace (colors, surface normals, distances, IDs).
+
+Created rcode2bmp script to create images from new rcode_* output maps.
+
+Improved efficiency of rmtxop in cases where matrix multiplication is
+faster evaluated right-to-left, as when the final component is a
+column vector.  Also added ability to apply trailing unary operators
+(-t, and -s or -c) to resulting matrix.
+
+Added new depth, normal, and ID file types to radcompare.
+
+Added BigEndian= header line for automatic byte-swapping in rmtxop
+and radcompare.
+
+Added new "turbo" palette to falsecolor (thanks to Taoning).
+
+Nathaniel Jones created the "dcglare" program for annual glare
+simulations when the sun and sky are visible through the window.
+Tutorial is posted at
+"https://github.com/nljones/Accelerad/wiki/The-Imageless-Method-for-Spatial-and-Annual-Glare-Analysis".
+
+Added support for loading RGBE images into matrices in dctimestep.
+
+Added -y option to gensky and gendaylit to support more accurate Michalsky
+solar position calculation.
+
+Changed rsplit, so specifying a space as the separator parses words
+between whitespace.
+
+Added ability of vwrays, pinterp, and pmblur2 to read encoded depth files.
+
+Added -o RxCxR1xC1 facility to perform blocking in rcollate.
+
+Made it so number of segments in genworm, genrev, and gensurf can be
+given as expressions of previously defined variables, etc.
+
+Added -D and -n option to gendaymtx to output sun description and skip
+matrix output on request.  A -M option was also added to output solar
+modifiers for rcontrib.  Support also added for leap days in WEA input.
+Enhancements sponsored by Ladybug Tools.
+
+Updated eplus_uvf to work with IDF version 9.x, checking version number.
+
+Fix to glarendx issues with dgi calculation.
+
+Made it so rmtxop and dctimestep undo any exposure applied to Radiance
+pictures they may load.
+
+Added robjutil utility to manipulate Wavefront .OBJ files.
+
+Fixed a crash related to rtrace -om or -oM with mesh instances containing
+materials.
+
+Improved rtrace flushing function to handle any value for -x without
+deadlock on controlling process.
+
+Eliminated unnecessary start-up procedures for rtrace when only ray-casting
+is needed (i.e., no tracing or value output).
+
+Improved isotropic sampling method in bsdf2ttree using "zipper" approach
+applied in genBSDF.
+
+Added limit to memory used by high-resolution tensor tree BSDFs for
+cumulative cache during MC sampling (rendering).  Limit set to 250MBytes
+per BSDF for standard architectures.
+
+Added -n and -s options to bsdf2ttree to provide some user control
+over super-sampling.
+
+Improved surface normal codec used by ambient file to store orthonormal
+directions exactly.
+
+Improved peak extraction method, which was undervaluing transmission
+in many cases.
+
+New version of evalglare from Jan Wienold.
+
+Added -u option to gendaymtx to elide data columns (time steps) when
+the sun is not visible above the horizon.
+
+=========================
+Version 5.4
+
+Added rcollate -c option to force operation to continue even if it
+seems unnecessary.  Made tool more robust.
+
+Added -t option to rcontrib (and rfluxmtx) to report progress after the
+given number of seconds.
+
+Added "test" target to makeall to run unit tests.
+
+Modified bsdf2ttree to allow different parameters per input SIR file.
+
+Fixed issues with very large matrix files (> 2GB) in dctimestep, rmtxop,
+and rcollate.
+
+Added -rf and -rb options to rmtxop to load front or back reflectance
+matrix data from XML file rather than transmission.  (Lars Grobe suggested.)
+
+Improved behavior for coincident surfaces with different materials.
+Rather than returning one surface or the other based on floating-point
+vagaries, opaque materials are now preferred over transparent ones.
+If the materials are both transparent or both opaque, then whichever
+surface appeared later in the scene description will be selected.
+This came of a request for consistent behavior with legal CAD output
+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.
+
+Added pabopto2bsdf -g option to cull near-grazing scattering to avoid
+issues with noise and negative values.
+
+Increased default dynamic range from 32 to 100 in pcond and normtiff.