--- ray/doc/man/man1/bsdfview.1	2017/08/11 23:00:10	1.2
+++ ray/doc/man/man1/bsdfview.1	2017/10/18 19:30:48	1.5
@@ -1,4 +1,4 @@
-.\" RCSid "$Id: bsdfview.1,v 1.2 2017/08/11 23:00:10 greg Exp $"
+.\" RCSid "$Id: bsdfview.1,v 1.5 2017/10/18 19:30:48 greg Exp $"
 .TH BSDFVIEW 1 8/11/2017 RADIANCE
 .SH NAME
 bsdfview - view a BSDF representation
@@ -7,6 +7,8 @@ bsdfview - view a BSDF representation
 [
 .B "\-q {Hi|Med|Lo}"
 ][
+.B \-t
+|
 rad options
 ]
 input ..
@@ -14,12 +16,16 @@ input ..
 .SH DESCRIPTION
 .I Bsdfview
 renders a BSDF description interactively.
-This is a script that creates a rad input file (RIF) 
-then calls
+This is a script that creates a
 .I rad(1)
-to make an octree via
+input file (RIF),
+which builds an octree via
 .I bsdf2rad(1),
-then views the scene interactively.
+then renders the scene interactively or calls the
+.I trad(1)
+graphical user interface if the
+.I \-t
+option is given.
 .PP
 The input is either a single XML file, such as might be produced by
 .I genBSDF(1),
@@ -30,7 +36,9 @@ or up to four scattering interpolation representation 
 might be produced by
 pabopto2bsdf(1).
 .PP
-A rad input file will be produced, whose name matches the root of
+A
+.I rad
+input file will be produced, whose name matches the root of
 the first input file but with any leading path removed (i.e., in
 the current directory).
 This RIF may be reused for subsequent viewing and rendering via
@@ -73,8 +81,37 @@ A parallel view of both transmission hemispheres from 
 Additionally, all the standard views that
 .I rvu
 defines will be available (e.g., "xZ", "zl", etc.).
+.PP
+Since a
+.I rad
+input file is created by the script, it may be used
+in subsequent runs as long as the temporary files remain.
+These are typically kept until the next reboot of the operating
+system, so re-running
+.I bsdfview
+with the same arguments will not require re-running
+.I bsdf2rad
+or
+.I oconv.
+Thus, start-up will be much quicker, unless the temporary files have
+been removed.
+In this case, the script may exit with an error indicating that the
+.I rad
+input file needs to be removed.
+.PP
+This input file may also be re-used directly from the command line using
+.I rad
+or
+.I trad(1).
+This may be useful for generating RADIANCE pictures corresponding
+to the above standard views.
+If no interactive run is desired, start
+.I bsdfview
+with the
+.I "-v 0"
+option.
 .SH AUTHOR
 Greg Ward
 .SH "SEE ALSO"
 bsdf2klems(1), bsdf2rad(1), bsdf2ttree(1), genBSDF(1),
-objview(1), oconv(1), pabopto2bsdf(1), rad(1), rvu(1)
+objview(1), oconv(1), pabopto2bsdf(1), rad(1), rvu(1), trad(1)