--- ray/doc/notes/ReleaseNotes	2011/10/26 16:48:01	1.191
+++ ray/doc/notes/ReleaseNotes	2022/04/11 18:08:19	1.414
@@ -1720,7 +1720,7 @@ Added -n option to rtrace for executing on multiple co
 using new rayfifo calls.
 
 =====================
-Version 4.1
+Version 4.1 (Released 11/04/2011)
 
 Changed ranimate behavior so remote login under a different user
 doesn't necessarily require the presence of the originating user's
@@ -1805,3 +1805,742 @@ when specular component was below -st threshold in non
 Checked in cross-platform cmake build system created by Bill Hoffman
 of KitWare and sponsored by NREL.  This includes a qt-based
 driver for rvu, which is built in the new subdirectory src/qtrvu.
+
+=====================
+Version 4.2 (Release date 7/31/2014)
+
+Axel Jacobs added -cp and -palettes options to falsecolor.
+
+Fixed bug in matrix output of genBSDF introduced shortly before 4.1 release.
+
+Made rvu more responsive in multi-processing mode when changing parameters.
+Explicit "new" command not needed to show changes, because it goes back
+to "immediate mode" once something is changed.  Processing will be slow
+but response time quick until next "new" command.
+
+Fixed major bug in transmitting proxy material sampling.
+
+Patched cmake build tools (changes by Zack Galbreath).
+
+Removed requirement for pflip -h to be given input file (can pipe from stdin).
+
+Added "Number of processes" slider to trad "Action" pane to control rad -N
+option for rvu and batch rendering.
+
+Added -c option to vwrays to repeat pixels for rtcontrib.
+
+Reworked rtcontrib program and renamed to rcontrib.  New version runs much
+faster, especially on multiprocessor systems, and doesn't require as much
+memory.  No longer calls rtrace; instead does all the work itself.
+
+Added -d option to genskyvec to produce direct-only (sun no sky) vector.
+
+Added Ashikhmin-Shirley anisotropic BRDF model (ashik2) with help
+from Nicolas Boneel.
+
+Added Ruby rewrite of objview.csh by Rob Guglielmetti.
+
+Fixed bug in reciprocity for tensor tree BTDF representations.  Thanks
+to Andy McNeil for identifying the problem.
+
+Added MNAME and ZNAME variables to ranimove for debugging & testing.
+
+Created pmblur2 command to take motion and depth buffers from ranimove
+to compute a better motion blur.
+
+****** COMPATIBILITY CHANGE ********
+Changed BSDF routines to use updated/corrected XML specification and
+removed depracated BSDF support from mkillum.
+
+Fixed behavior of i/o flushing in rcontrib with -c > 1 (averaging).  Thanks
+to Lars Grobe for help identifying this problem.
+
+Fixed bug in depth-of-field blur where view distance was measured from
+fore clipping plane rather than viewpoint.  Thanks to Peter A-B for
+pointing this out.
+
+Added options to dctimestep to allow multiple time steps (-n)
+and multiple output pictures or sensor files (-o).  Also added -i
+option to specify float (-if) or double (-id) input for sky matrix.
+
+Created gendaymtx program to compute annual sky patch matrix based
+on Ian Ashdown's implementation of Perez all-weather sky model.
+Output can be sent directly to dctimestep in ASCII or binary stream.
+
+Replaced existing gendaylit.c with improved version from Wendelin Sprenger
+and Jan Wienold of ISE.
+
+Improved accuracy of ambient calculation for large -ad settings.  Thanks
+to Lars Grobe for noticing the problem.
+
+Added -r option to gendaymtx to rotate the sky the specified number of
+degrees about the zenith as suggested by A. McNeil.
+
+Axel Jacobs added -pal eco color map that does a blue-red-yellow scale.
+
+Created bsdf2klems tool to convert from various BSDF representations to
+Klems basis matrix in XML file.
+
+Fixed problem with inappropriate reciprocity enforcement on tensor
+tree reduction in genBSDF.  (Thanks to A.McNeil for discovering issue.)
+
+Fixed bug in isotropic tensor tree sampling for impinging rays
+exactly normal to surface.  Thanks to Peter Apian-Bennewitz for
+discovering and pointing out the error.
+
+Fixed double-counting bug in mirror material with alternate type.
+Thanks to David Geisler-Moroder for spotting the problem and helping
+to fix it.
+
+Created rcollate program to resize and transpose matrix data for Andy
+McNeil's 5-phase annual simulation method.
+
+Added epw2wea conversion program by Christoph Reinhart.
+
+Implemented Perlin's improved noise function with help from Rahul Narain.
+This will change the appearance of renderings using this function.
+
+Added "origin" command to rvu as requested by John Mardaljevic
+to place view origin at selected point in scene.
+
+Switch to Perl versions of objview and objpict written by Axel Jacobs.
+
+Improved rendering speed of scenes with aliases by not entering new
+modifiers into table if they are the same as the previously defined
+modifier for that name.
+
+Made it so icalc and rcalc search RAYPATH directories for *.cal files
+given on command line.  This simplifies script writing and makes these
+utilities consistent with other tools in Radiance.
+
+Added triangulation routine to handle convex polygons in obj2mesh.
+
+****** COMPATIBILITY CHANGE ********
+Made backface visibility apply to all material types, including
+transparent and translucent materials (except dielectric and interface).
+This makes the option useful in cases where adjacent trans surfaces
+are placed next to each other by a modeler that only understands
+volumetric objects.
+
+Changed dctimestep so that output matrices (-n > 1) are preceded by a
+header, and added support for float and double output formats with -o[fd].
+
+Introduced eplus_adduvf program to compute user view factors for EnergyPlus.
+
+Changed image-plane sampling in rpict to use Hilbert curve, which gives
+less of a brushed/striped appearance to output pixels with -u- (default).
+
+Added ltview and ltpict Perl scripts contributed by Axel Jacobs, inspired
+by Rob Guglielmetti.
+
+Added header variables for NROWS, NCOLS and NCOMP to help standardize
+matrix files.  This functionality has been incorporated into
+rcollate, gendaymtx, and dctimestep.
+
+Created rmtxop utility to operate on multi-component matrices.  This
+facilitates some daylight matrix calculations, and provides a general
+tool for manipulating matrix data.
+
+****** COMPATIBILITY CHANGE ********
+Introduced new Hessian-based error control in irradiance caching (ambient)
+calculation.  Since the format of the stored ambient values is different,
+the old files will be rejected with an error message and must be removed.
+The programs may be compiled with the -DOLDAMB option if this is a problem.
+
+Added -p option to rcontrib to set function file parameters on a per-modifier
+basis to simplify bin evaluation.
+
+Created rfluxmtx program to compute flux transfer matrices from a sender
+surface to one or more receiver surfaces.  (Renamed the file klems_int.cal
+to klems_full.cal in the process.)
+
+Added "-c" option to getinfo to execute command on data segment.
+
+================================
+Version 5.0 (Released 9/18/2015)
+
+Changed rmtxop so it writes out same type as lesser of inputs unless
+directed otherwise using -f? option.
+
+Changed order of oconv arguments in rfluxmtx so user can specify input
+octree using -i option at the end instead of (or in addition to) a
+list of scene files.
+
+Added support for argument expansion to rfluxmtx and bug fixes.
+
+Fixed bug in indirect hemisphere sampling for some corner cases.
+
+Added default specular lobe to BSDF interpolation.
+
+Set minimum number of shadow checks before direct optimization (4).
+
+(Above changes included in 4.2.1 patch release.)
+
+****** COMPATIBILITY CHANGE ********
+Made header input and output the default behavior for dctimestep and
+genskyvec.
+
+****** COMPATIBILITY CHANGE ********
+Changed pabopto2bsdf default behavior to add 90-degree rotation
+to bring pgII's definition of "up" in line with Klems axis
+conventions.  Introduced a new header variable "upphi" to
+control this added rotation.  Using "#upphi 90" in each
+BSDF input file gets back the original behavior, where it
+assumes that the up direction is 90-degrees from the X-axis.
+The default value of 0 corresponds to PAB's definition of
+the X-axis as being "up".
+
+Fixed bug in rsensor related to having many rows (altitude) and
+few columns (azimuth) in sensitivity file.
+
+Fixed floating point round-off error in new Hessian calculation
+for some sytems (Windows, primarily).
+
+Fixed bug in tensor tree BSDF code that caused bus error on
+some systems, and may have been source of other errors as well.
+
+(Above changes included in 4.2.2 patch release.)
+
+Improved ambient extrapolation to avoid zero values.  Actual
+threshold set to 5% of recorded value.
+
+Changed anisotropic Gaussian and Ashikhmin models so that
+illegal orientation vectors are dealt with more gracefully.
+
+Created wrapBSDF tool and incorporated into genBSDF along
+with new rfluxmtx computation.
+
+Initial check-in of Roland Schregle's photon map integration.
+New 5.0a version designation as suggested by Andy McNeil.
+
+Added left-hand coordinate sytems to rfluxmtx to correct
+problems with coordinate axis orientations pointed out by
+David Geisler-Moroder.
+
+Added color output to genBSDF (+C option) and support for
+color rendering of Klems and tensor tree data.
+
+Fixed another bug in rsensor that caused rays to be generated
+on opposite side of hemisphere even where sensitivity was zero.
+
+Fixed bug discovered by Jacob Jonsson in Klems BSDF
+interpolator that caused it to over-predict normal
+transmittance and reflectance.
+
+Added ability to read input from commands in dctimestep
+and rmtxop.
+
+Added photon map support to rad.  Fixed some double-counting
+issues in photon-mapping spotted by David Geisler-Moroder.
+
+Added photon map support to trad.
+
+Fixed bug in antimatter source testing when antimatter
+definition follows potential obstructor in input.
+
+Fixed issue with missing character type identifier at head
+of genBSDF XML output.
+
+Prompted by Roland S., added option to have pcompos -a order
+rows from top rather than bottom of image.
+
+Changed dctimestep to accept matrix as well as BTDF input
+in the VTDs invocation mode.  This permits the output of
+rmtxop to be used in a pinch when combining multiple BTDF
+layers, although interreflection between layers is not
+accounted for properly as it is in the WINDOW program.
+
+Added Jan Wienold et al.'s evalglare to distribution.
+
+Hopeful fix to deadlock issue under Mac OS X 10.10.x (Yosemite).
+
+Fixed early exit of rcontrib with internal error (sample behind sender)
+discovered by Rob G.
+
+=================================
+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.
+
+Added ability to give quoted strings to output= directive in rfluxmtx.
+
+****** COMPATIBILITY CHANGE ********
+Added ability to digest color (CIE-XYZ) input in pabopto2bsdf.
+This change alters the .sir (interpolant) format, so these files
+will need to be regenerated.  Use the new "#colorimetry: CIE-XYZ" tag
+to enable on input.
+
+Rewrote bsdf2klems to support tristimulus color and call wrapBSDF.
+Did the same for bsdf2ttree.  Function specifications still gray only.
+
+Reduced a problem where rvu or rholo would be slow to quit when
+run with many processes on a large model or one with a large
+ambient file (taking lots of memory).  We were waiting for
+processes to quit one-by-one, which takes some time for each
+process as it disentangles its shared memory.  We now
+wait for all the processes together, so they can disentangle
+in parallel.  It can still take up to a minute in some cases,
+but not 10 minutes like it was taking before the fix.
+
+Enabled ambient cache value corral for all levels, not just final two.
+This may reduce errors in certain pathological scenes.
+
+Added -in option to rcalc, rlam, and total to limit the number of
+input records in hopes of circumventing Windows EOF issues on binary data.
+Also added -on option to rcalc and total for logical symmetry.
+
+Increased modifier limit to 10,000 in rcontrib.
+
+Fixed issues with glrad and added zoom response to mouse wheel input.
+
+Added missing definition of "ashik2" material type to reference manual.
+
+Changed genBSDF to calculate device thickness assuming Zmax==0 so
+pkgBSDF will generate correct proxy geometry.
+
+Created pabopto2xyz tool to combine different sensor measurements
+into a single CIE-XYZ measurement file for color BSDF interpolation.
+
+Jan Wienold updated evalglare to version 1.30
+
+Roland Schregle added out-of-core photon mapping routines, which
+may be compiled using the PMAP_OOC macro.
+
+Added -a option to getinfo for easy addition of header lines.
+
+Fixed issue with multiple records on picture output in rcontrib (and rfluxmtx).
+Credit to Sarith Subramaniam for pointing out the problem.
+
+Made mkillum more tolerant of non-planar polygons in its sampling routines.
+
+Added "-recover" option to genBSDF to pick up where it left off.
+
+Fixed genBSDF issue that was created incorrect normalization of
+Klems output.  Thanks to David G-M and Christian Knoflach for
+discovering the error.  Also improved sampling of indirect irradiance
+that showed some slight bias due to poor sample collision avoidance.
+
+Fixed long-standing issue with -aa 0 neglecting textures in calculating
+surface shading.
+
+Fixed bug in ranimove introduced during photon map integration.
+
+Added check for steep sections of BSDF in pabopto2bsdf, creating narrower
+peakes in those places and mitigating some normalization issues.
+
+Added view360stereo.cal by Mark Stock to handle 360-degree over/under
+stereo views.
+
+Added MAX2SHADE macro to place limit on number of light sources
+to precheck for obstructions.  (Currently set to 200.)  This
+avoids excessive start-up times for scenes with many light sources.
+Thanks to Axel Jacobs for pointing out the problem.
+
+Added -v option to obj2mesh to print out mesh statistics.
+
+Rewrote bsdf2rad from ground up and made it a standard part of build.
+
+Fixed bug in orientation of Reinhart/Tregenza sample generator in rfluxmtx.
+
+Added ability to perform shadow-testing through unproxied BSDFs with strong
+through (direct-direct) component.
+
+Added {+|-}a options to genBSDF and bsdf2ttree for switching off reciprocity
+averaging.
+
+Added bias to see through BTDFs with a strong "through" component
+rather than scattering view rays.  This is in lieu of peak extraction,
+which looked to be too difficult from an implementation standpoint.
+
+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.
+
+Added -o and -n options to genbox to create .OBJ output and segment
+edges and corners for transparent materials.  Also added -s option
+to control smoothing for .OBJ and Radiance with segmented rounding.
+
+Made it so robjutil with the +r option for Radiance output now
+produces normal smoothing unless normals are removed with -n.
+
+Added exposure preservation to pcompos when possible (i.e., when
+there is only one input or inputs agree on exposure).
+
+Added -DSHARP_RGB compile-time option to use sharp RGB color space
+rather than historic default.  This can make for more accurate color
+calculations, but requires that materials be recalibrated.  The
+PRIMARIES= line is also produced on output from rpict or rvu with
+the correct set of primaries based on how the system was compiled.
+
+Added automatic flushing to the output of total, except when the -r
+(running subtotals) option is used.
+
+Improved behavior of little-used -aw option, so that it avoids sea-level
+rise caused by adding its own estimate back into the ambient level remainder.
+It ended up being simple enough to derate the final average by the factor
+corresponding to average surface absorpition, thus removing the average
+from the final bounce estimate.
+
+Introduced ies2rad upgrades by Randolph Fritz.  Randolph says it
+fixes the following problems:
+
+	1. Generates correct Radiance geometry for spheres in 1995, 2002,
+	and 2019 IES files.
+
+	2. Generates correct Radiance geometry for vertical cylinders that
+	are taller than they are wide.
+
+	3. Ignores the file source ("File Generation Type") field in the
+	2019 version of the file, which would otherwise be incorrectly used
+	as an output multiplier.
+
+    It also offers the following enhancements:
+
+	1. Shape information is included in the .rad file comments.
+
+	2. 1995, 2002, and 2019-version luminous opening geometry is
+	accounted for.
+
+	3. The 2002 and 2019 IES file versions are recognized and
+	processed appropriately.
+
+	4. I have made an attempt to do something intelligent with less
+	common "luminous opening" shapes in the 1995, 2002, and 2019 versions
+	of the standard, though I have not implemented any support for new
+	geometry; approximations are substituted and warning messages issued.
+	Unfortunately, this code is not tested, since I don't have any IES
+	files that use these shapes.
+
+Added support for depth-of-field blurring in vwrays using -pd option.
+Also, made -c count work with vwrays -i, producing multiple samples
+per indicated pixel position.  At the same time, support for the -pd
+option was added to rtpict, which calls on vwrays for its samples.
+
+Fixed issue with BSDFs that didn't obey reciprocity, where direct
+sampling wasn't following exactly with indirect sampling.  This was
+discovered and reported by Jon Sargent.
+
+Created checkBSDF tool to test XML BSDF reciprocity and perform similar
+sanity checks.
+
+Added -O option to pvalue and pextrem to report watts/sr/m^2 even if
+picture is XYZE.
+
+Made subtle changes to header i/o routines to preserve alignment in
+binary file formats to enable memory-mapping.  Implemented memory-mapped
+matrix loading in rmtxop for binary double files.
+
+Removed ambient value sorting, which was written when ambient caches
+could overwhelm available memory.  This is rarely the case these days,
+and the added code complexity and updating of cache values with LRU
+counts dirties pages that would otherwise remain clean, so it was
+often a loss even when VM was an issue.
+
+Added iso2klems script to compute a Klems BSDF based on specular
+and diffuse measurements as a function of incident angle.
+
+Fixed issue with over-counting diffuse component during aBSDF
+peak extraction.
+
+Added dctimestep -x and -y options to specify image dimensions
+for multiple outputs corresponding to result vectors.
+
+Added -P option to rcalc to pass formatted input when cond is <= 0.
+
+Created rcrop utility for cropping matrices and pictures more
+conveniently, correcting view information.  Expect it to be handy
+for extracting rows and columns from matrices, mostly.
+
+Changed pcomb so -o option elides original exposure values
+from indented source headers.
+
+Added getinfo -r option, which is similar to -a except it will
+replace indicated lines with new ones.
+
+Slight change to vwrays -d option to not spit out "-ld-", and to
+produce "-ld+" without requiring input picture as argument.
+
+Added automatic overture calculation to rtpict with -n > 1 if
+ambient cache is on and file is named.  If straight image output
+is requested, we randomize all samples and avoid cache collisions.
+
+Added cnt -s option to shuffle output.