--- ray/doc/man/man1/rtcontrib.1	2005/06/02 04:47:26	1.7
+++ ray/doc/man/man1/rtcontrib.1	2005/06/10 20:53:55	1.10
@@ -1,4 +1,4 @@
-.\" RCSid "$Id: rtcontrib.1,v 1.7 2005/06/02 04:47:26 greg Exp $"
+.\" RCSid "$Id: rtcontrib.1,v 1.10 2005/06/10 20:53:55 greg Exp $"
 .TH RTCONTRIB 1 5/25/05 RADIANCE
 .SH NAME
 rtcontrib - compute contribution coefficients in a RADIANCE scene
@@ -7,6 +7,8 @@ rtcontrib - compute contribution coefficients in a RAD
 [
 .B "\-n nprocs"
 ][
+.B \-r
+][
 .B "\-e expr"
 ][
 .B "\-f source"
@@ -15,7 +17,10 @@ rtcontrib - compute contribution coefficients in a RAD
 ][
 .B "\-b binv"
 ]
-.B "\-m mod .."
+{
+.B "\-m mod | \-M file"
+}
+..
 [
 .B $EVAR
 ]
@@ -37,6 +42,14 @@ settings.
 These modifiers are usually materials associated with
 light sources or sky domes, and must directly modify some geometric
 primitives to be considered in the output.
+A modifier list may also be read from a file using the
+.I \-M
+option.
+The RAYPATH environment variable determines directories to search for
+this file.
+(No search takes place if a file name begins with a '.', '/' or '~'
+character.)\0
+.PP
 The output of
 .I rtcontrib
 has many potential uses.
@@ -59,7 +72,9 @@ specification.
 If a destination begins with an exclamation mark ('!'), then
 a pipe is opened to a command and data is sent to its standard input.
 Otherwise, the destination is treated as a file.
-(An existing file of the same name is clobbered.)\0
+An existing file of the same name is clobbered, unless the
+.I \-r
+option is specified, in which case data recovery is attempted.
 If an output specification contains a "%s" format, this will be
 replaced by the modifier name.
 The
@@ -109,8 +124,6 @@ Unlike
 will search the RADIANCE library directories for each file given in a
 .I \-f
 option.
-(No search takes place if a file name begins with a '.', '/' or '~'
-character.)\0
 .PP
 If no
 .I \-o
@@ -194,7 +207,7 @@ To compute an array of illuminance contributions accor
 rtcontrib -b tbin -o sky.dat -m skyglow -b 0 -o ground.dat -m groundglow
 @render.opt -f tregenza.cal scene.oct < test.dat
 .SH ENVIRONMENT
-RAYPATH		path to search for -f files
+RAYPATH		path to search for -f and -M files
 .SH AUTHOR
 Greg Ward
 .SH "SEE ALSO"