--- ray/doc/notes/ReleaseNotes	2005/05/25 04:44:25	1.75
+++ ray/doc/notes/ReleaseNotes	2019/08/12 02:26:46	1.352
@@ -1140,7 +1140,7 @@ of recursive routines using sets to avoid overrunning
 the stack limit.
 
 ==============================
-Version 3.6
+Version 3.6 (Released 10/21/04)
 
 Modified 4-byte RGBE encoding routine to avoid problems
 when one or two primary values is negative and the other(s)
@@ -1343,7 +1343,7 @@ Fixed bug in rcalc where it sometimes wasn't parsing t
 correctly.
 
 =====================
-Version 3.7
+Version 3.7 (Released 7/25/05)
 
 Fixed bug in source occluder cache which caused consistency error
 for distant sources and mist materials.  (Thanks to Mark Stock for
@@ -1382,7 +1382,7 @@ care to support officially due to its machine-dependen
 Fixed bug that caused incorrect reporting of non-surface in set when
 mixing meshes and instances.  (Thanks to Jack de Valpine for discovery.)
 
-Fixed innacuracy in calculation of diffuse transmission in the presence
+Fixed inaccuracy in calculation of diffuse transmission in the presence
 of pure specular (Fresnel reflection) using "trans" material.  Thanks
 to Christoph Reinhart for pointing out the error.
 
@@ -1452,3 +1452,857 @@ Increased maximum number of input pictures in pcomb an
 Created rtcontrib program for computing ray contribution coefficients.
 This tool may be used to do standard optical ray tracing or daylight
 coefficient calculations for annual simulations, among other uses.
+
+Added tilde ('~') output option as part of the -o* specification of
+rtrace.  This permits ray trees to be parsed more easily in binary
+output mode, as needed by rtcontrib.
+
+Implemented Russian roulette ray termination with -lr <= 0.
+Made -lr -10 the default in rtcontrib.
+
+Made rtcontrib -f option search RAYPATH directories.
+
+Made it so -o option of rtcontrib can pipe -o output to a command.
+
+Added -if and -of options to total for binary i/o (following rcalc mold).
+
+Switched default options in rtrace to use Russian roulette.  (Rpict and rvu
+still use biased ray termination.)
+
+Added rtcontrib -r option to recover partial output.
+
+Added -u rendering option for pure Monte Carlo sampling.
+(Got rid of -DMC compile option, which this makes superfluous.)
+
+Changed -t option of rlam to accept strings as well as single characters.
+
+Fixed bug in rcalc with -l option where it would sometimes go into an
+infinite loop.
+
+Fixed truly ancient bug in bounding box computation for cones, which
+could (and did) cause missing segments.
+
+Added -z option to normtiff to output LZW-compressed files.
+
+Last change to total causes it to produce results when it sees an empty
+line on the input.  This was not intentional, but I decided I like this
+behavior so I documented it rather than changing it.
+
+=====================
+Version 3.8 (Released 10/17/06)
+
+Fixed Russian roulette ray termination, which was doing the opposite of
+what it should have been doing, resulting in overestimated values below
+minimum ray sampling weight (serious).
+
+Changed mksource to use 98th percentile (rather than 99th) for threshold.
+
+(Above changes included in 3.7.1 patch release.)
+
+Eliminated writing of EXPOSURE= line in ra_tiff -r when source TIFF
+does not have STONITS set.
+
+Fixed bug in ambient calculation that caused black values for multiple
+bounces in some scenes.  Thanks to Mark Stock for creating and sharing
+the sophisticated test scene that demonstrated this problem.
+
+Fixed bug in antimatter using Russian Roulette sampling.
+
+(Above changes included in 3.7.2 patch release 22 Aug 2005.)
+
+Created fieldcomb script to combine alternate fields in a rendering
+sequence.  (Development generously sponsored by Iebele Abel.)
+
+Added missing preload of mesh objects for more efficient memory use
+during parallel rendering -- this was a serious oversight.
+
+Created ran2tiff program to automate exposure setting of animation
+sequences using a moving histogram in combination with pcond, and
+converting frames to TIFF.
+
+Eliminated SPEED macro from makeall and source tree.
+
+Added -pj option to vwrays to allow jittering of sample locations.
+
+Fixed bug in rtcontrib where it occasionally missed writing the
+final bin file.  (Pretty serious, actually.)
+
+Added -Dfseeko=fseek to MACH= line for linux, as fseeko(3) seems to be
+broken in current versions of Linux.  (Need to remove this later.)
+
+Rearranged struct's for better efficiency on 64-bit architectures.
+
+Added -i option to rlam so it works with binary input formats.
+
+Added rtcontrib -bn option to specify number of bins and fixed bug
+in recovery of files containing multiple values per record.
+
+Added rtcontrib -fo option to write over existing files, which it now
+refuses to do without this option.
+
+Made rtcontrib flush output when handed a zero-length ray vector,
+to match behavior of rtrace.
+
+Improved color scale for falsecolor output.
+
+Added threshold test for Fresnel approximation to prevent its use
+on smooth surfaces with unrealistically low specularities (less than 1.8%).
+Water has a specular reflectance of 2.1% at room temperture.
+
+Removed NICE macro settings in rpict and rtrace, which was slowing down
+the processes under Mac OS X (10.4) by about 60% due to processor napping.
+
+Made xform, replmarks and rad2mgf handle quoted modifiers and names properly.
+
+Fixed problem in genblinds, where it was generating slats that were too
+wide with the +/-r option.  (Thanks to Helena Buelow-Huebe for discovering
+this bug.)
+
+Fixed bug in ra_ppm for 16-bit/sample i/o, where it was getting the byte
+order wrong (apparently).
+
+Added -V option to rtcontrib to report actual contributions, rather than
+just ray coefficients.
+
+Fixed bug in ranimate that caused it to fail in continuation of renderings.
+
+Renamed librt.a to librtrad.a, to avoid conflict on Solaris. Almost
+everything now gets linked to -lrtrad instead of -lrt.
+
+Fixed problem with large sample sets, so -u+ option now is truly random.
+Thanks to Rick Mistrick and Younju Yoon for identifying this problem,
+which was related to a poorly designed hash function.
+
+Changed -u+ to be the default setting in rtrace (only).
+
+Fixed binary i/o for rlam and vwrays under Windows.
+
+Added tmCvLums() to tone-mapping routines using a 16-bit lookup table
+on IEEE floats, which is also used to improve speed of COLOR conversions,
+especially on machines with slow log() calls.  The first call to
+tmCvLums(), tmCvGrays(), or tmCvColors() initializes the table.
+
+Created optics2rad.csh script to convert from Optics 5 material output
+to something correct for Radiance.  Built on old glazing.cal function,
+which is actually incorrect so removed from the distribution.
+
+Fixed nuisance bug in ximage under some SGI machines that caused it to
+choose an inappropriate visual and display incorrect colors.  (Thanks
+to Oskar Itzinger for debugging the problem.)
+
+Fixed long-standing inaccuracy of pcompos -t and +t thresholding options.
+
+Fixed bug in handling of views with tabs rather than spaces.
+
+Fixed bug related to alias of alias.
+
+****** COMPATIBILITY CHANGE ********
+Changed default sky turbidity in gensky from the original default of
+2.75 to the CIE 110-1994 standard value of 2.45.  Thanks to Marilyne
+Anderson of MIT for pointing out this discrepancy.
+
+Added -o option to ra_xyze to produce original pixel values.
+
+Fixed bug in tracing of virtual sources, where intervening glazing was
+not being accounted for properly.
+
+Added -h option to pcompos and pcomb to eliminate verbose headers.
+
+=====================
+Version 3.9 (Released 3/30/08)
+
+Added -spec option to falsecolor to restore original spectral color scale.
+Also added "-s auto" option to automatically set the maximum value.
+
+Added byte-swapping input and output to rcalc.
+
+Additional error-checking for source surfaces.
+
+Re-fixed bug in octree code that caused it to allocate 8 times as
+much memory as it actually used(!) -- this was pointed out way back
+in 1999 by Erik Reinhard and Erik Jansen, but the fix they gave me
+got lost in the slightly broken release process at the time.  This
+should make a big difference in memory usage, especially for the
+new mesh primitive.  (I measured 30% less memory usage.)
+
+Corrected ray weights for material mixtures.
+
+Reduced the default -n setting for obj2mesh to take better advantage
+of the smaller octree structure size.
+
+Fixed bug in shadow cache where it was adding surfaces with antimatter
+holes cut in them to the obstructor list.  Thanks to John Mardaljevic
+for discovering and reporting the problem.
+
+Adding ability in mkillum to incorporate BSDF data in calculation.
+Internal interface (raypcalls) now used in place of rtrace process(es).
+
+Fixed pixel alignment in pcomb for size reduction and enlargement.
+
+Allow rtcontrib user to set -P and -PP options for persistent rendering.
+The only caveat is that -n setting > 1 requires -PP rather than -P.
+
+Added -c option to rtcontrib to facilitate cumulative calculations.
+
+****** COMPATIBILITY CHANGE ********
+Fixed long-standing bug in source.cal, which caused it to produce
+reversed anisotropic photometric distributions due to the
+misorientation of the y-axis.  Thanks to Zack Rogers for discovering
+and helping debug this problem.
+
+Fixed long-standing bug in replmarks, where triangles with X-side
+aligned with Z-axis would cause incorrect rotations.  Thanks to
+Zack Rogers for finding this error.
+
+Added rsensor program to compute sensor signal for daylighting controls.
+Funding for this component was provided by the Architectural Energy
+Corporation in Boulder, CO, and directed by Zack Rogers.
+
+Added "planisphere" (stereographic) fisheye view type for traditional
+daylighting analysis.  Feature requested & explained by Axel Jacobs.
+
+Modified -c option to rtcontrib so it can take a number of input
+rays to average over, rather than only produce a single accumulated
+record (which can now be done with -c 0).
+
+=====================
+Version 4.0 (Released 3/12/10)
+
+Added -n option to rvu to provide parallel rendering.
+
+****** COMPATIBILITY CHANGE ********
+Changed ".pic" extension to ".hdr" in all sources and documentation
+to improve interoperability with other software, since this has become
+the de facto extension for Radiance RGBE and XYZE pictures.  Since file
+extensions were never more than a convention in Radiance, this does not
+affect operation, but may require the update of scripts, etc. written
+by others that assume the ".pic" suffix for Radiance output.
+
+Added -N option to objview to support multiprocessing.
+
+Improved sampling of circular sources (source, sphere, ring types) with
+quite a bit of help from David Geisler-Moroder.
+
+Added "rpict" and "rvu" variables to rad, and made these as well as
+the "oconv", "mkillum" and "pfilt" variables accept an alternate
+command path in each case.  Change suggested by Lars Grobe based
+on similar Radzilla (radz) facility by Carsten Bauer.
+
+Fixed rad -v N specification to use actual view name if one.
+
+Fixed error in mkillum calculation where it neglected indirect
+source contributions from BTDF illum's.
+
+Added GMT and LATLONG header lines for Greenwich Mean Time and
+degrees North Latitude / East Longitude.
+
+Added gendaylit to distribution (finally).
+
+Added ability in vwright(1) to get view from command line arguments.
+
+Created genklemsamp(1) utility to generate samples suitable for
+BSDF-based annual calculations.  This is the first Perl script to
+be added to Radiance.  Hopefully, others will follow.
+
+Added klems_int.cal file to compute Klems bins for windows.
+
+Created genskyvec  utility to sample a particular sky and
+evaluate average radiance over the standard Tregenza sky patches.
+
+Created dctimestep program to compute a set of sensor values or
+a combined image for a particular time using the daylight
+coefficient method.
+
+Created src/rt/rayfifo.c for first-in/first-out handling of
+multiprocessing by raypcalls.c.
+
+Added -n option to rtrace for executing on multiple cores
+using new rayfifo calls.
+
+=====================
+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
+home directory.
+
+Changed standard transmission function normalization back to what
+it was in version 3.5, following recommendation of David Geisler-Moroder,
+who pointed out that the revised BTDF increased too much at grazing.
+
+Changed rad behavior with -N >1 on single view to call rpiece.
+
+Updated SCons build system for MINGW compilation, thanks to Christian
+Kohler.
+
+Added -u option to rlam for unbuffered output.
+
+Modified dctimestep to accept sky vector and daylight coefficient matrix
+or list of images to sum together, as suggested by Andy McNeil.
+
+Created genBSDF script to generate BSDF in Windows XML format.
+
+Modified mkillum to accept detailed geometry from BSDF XML files.
+
+Altered obj2rad to ignore zero normals (thanks to Jack de Valpine for
+suggestions and help).
+
+Fixed bug in genklemsamp that caused non-uniform sampling over surfaces.
+
+Fixed bugs in rhoptimize and rhcopy for 64-bit compilation.
+
+Made a change to avoid problem using gcc --fast-math compile option.
+
+****** COMPATIBILITY CHANGE ********
+Changed behavior of rtrace and rtcontrib so that every scanline is
+not flushed when both -x and -y are set.  This avoids flush delays
+in rtcontrib for large numbers of output files and delays while
+rendering images using rtrace with the -n option.
+
+Added ability for rsensor to output ray origins and directions
+rather than actually loading octree and computing sensor value.
+
+Fixed old bug in obj2rad where it would stop processing and
+report a syntax error if the "void" type is used in the map file.
+
+Updated reflection model according to EGSR 2010 paper by David
+Geisler-Moroder and Arne Duer.
+
+Replaced C-shell version of falsecolor with Perl script written
+by Axel Jacobs.
+
+****** COMPATIBILITY CHANGE ********
+Changed -sj (specular jitter) option to something called specular
+sampling (-ss), which if set less than 1 has the same behavior as
+the old -sj, but when set greater than 1, spawns multiple ray
+samples from semi-specular surfaces.
+
+Fixed bug noticed by Randolph Fritz that caused ambient sync errors.
+
+Fixed bug in findglare for reading picture files under Windows.
+
+Added options to pvalue to note other color spaces on reverse conversion.
+Thanks to Erich Philips for the feature request.
+
+Added BSDF data-driven material type with full sampling support.
+
+Added BRDF calculations to genBSDF.
+
+Bug fixes in rsensor thanks to help from David Geisler-Moroder.
+
+Added variable-resolution BSDF support in renderers and genBSDF.
+
+Created pkgBSDF program to extract BSDF geometry and put it
+together with surface description suitable for inclusion in
+a Radiance scene.
+
+Muted warning for "no light sources found" when there is at least
+one glow object and interreflections are on (-ab > 0).
+
+Fixed long-standing bug that caused underestimation of reflection
+when specular component was below -st threshold in non-metals.
+
+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
+
+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.
+
+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.
+
+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/util/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/util/normcodec.{h,c}.
+
+Created rcode_ident tool to create indexed identifier files.
+Code for loading these files is in src/util/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.