--- ray/doc/man/man1/vwrays.1	2003/12/09 15:59:07	1.2
+++ ray/doc/man/man1/vwrays.1	2021/12/04 16:29:29	1.12
@@ -1,10 +1,10 @@
-.\" RCSid "$Id: vwrays.1,v 1.2 2003/12/09 15:59:07 greg Exp $"
+.\" RCSid "$Id: vwrays.1,v 1.12 2021/12/04 16:29:29 greg Exp $"
 .TH VWRAYS 1 1/15/99 RADIANCE
 .SH NAME
 vwrays - compute rays for a given picture or view
 .SH SYNOPSIS
 .B vwrays
-.B "[ -i -f{a|f|d} | -d ]"
+.B "[ -i -u -f{a|f|d} -c rept | -d ]"
 {
 .B "view opts .."
 |
@@ -22,18 +22,35 @@ If a given pixel has no corresponding ray (because it 
 legal view boundaries), then six zero values are sent instead.
 .PP
 The
-.I -i
+.I \-i
 option may be used to specify desired pixel positions on the standard
 input rather than generating all the pixels for a given view.
+If the
+.I \-u
+option is also given, output will be unbuffered.
 .PP
 The
-.I -f
+.I \-f
 option may be used to set the record format to something other than the
 default ASCII.
 Using raw float or double records for example can reduce the time
 requirements of transferring and interpreting information in
 .I rtrace.
 .PP
+The
+.I \-c
+option repeats each pixel the given number of times (default is 1).
+This is most useful when sending rays to
+.I rcontrib(1)
+with the same
+.I \-c
+setting, providing a much faster way to average pixels over image sets.
+The
+.I \-pj
+and/or
+.I \-pd
+options should be used to jitter sample postions in most cases.
+.PP
 View options may be any combination of standard view parameters described
 in the
 .I rpict(1)
@@ -41,30 +58,37 @@ manual page, including input from a view file with the
 .I \-vf
 option.
 Additionally, the target X and Y dimensions may be specified with
-.I -x
+.I \-x
 and
-.I -y
+.I \-y
 options, and the pixel aspect ratio may be given with
-.I -p.
+.I \-pa.
 The default dimensions are 512x512, with a pixel aspect ratio of 1.0.
 Just as in
 .I rpict,
 the X or the Y dimension will be reduced if necessary
 to best match the specified pixel
 aspect ratio, unless this ratio is set to zero.
+The
+.I \-pj
+option may be used to jitter samples.
+The
+.I \-pd
+option specifies a world-diameter aperture for depth-of-field jittering.
+The default value of 0 for both options turns off all ray jittering.
 .PP
 If the
-.I -d
+.I \-d
 option is given, then
 .I vwrays
 just prints the computed image dimensions, which are based on the view
 aspect and the pixel aspect ratio just described.
 The
-.I -ld
+.I \-ld
 switch will also be printed, with
-.I -ld+
+.I \-ld+
 if the view file has an aft clipping plane, and
-.I -ld-
+.I \-ld-
 otherwise.
 This is useful for passing options to the
 .I rtrace
@@ -78,7 +102,7 @@ equal the maximum distance for each pixel, which will 
 correctly by
 .I rtrace
 with the
-.I -ld+
+.I \-ld+
 option.
 Note that this option should not be given unless there is an aft
 clipping plane, since the ray direction vectors will be normalized
@@ -86,8 +110,8 @@ otherwise, which would produce a uniform clipping dist
 .PP
 If a picture is given on the command line rather than a set of view options,
 then the view and image dimensions are taken from the picture file, and
-the reported ray origins and directions will exactly match the center of each
-pixel in the picture.
+the reported ray origins and directions will match the center of each
+pixel in the picture (plus optional jitter).
 .PP
 If a depth buffer file is given as well, then
 .I vwrays
@@ -101,19 +125,19 @@ for light rays leaving the scene surfaces to strike ea
 To compute the ray intersection points and returned directions corresponding
 to a picture and its depth buffer:
 .IP "" .2i
-vwrays scene_v2.pic scene_v2.zbf > scene_v2.pts
+vwrays scene_v2.hdr scene_v2.zbf > scene_v2.pts
 .PP
 To determine what the dimensions of a given view would be:
 .IP "" .2i
-vwrays -d -vf myview.vf -x 2048 -y 2048
+vwrays \-d \-vf myview.vf \-x 2048 \-y 2048
 .PP
 To generate a RADIANCE picture using
 .I rtrace
 instead of
 .I rpict:
 .IP "" .2i
-vwrays -ff -vf view1.vf -x 1024 -y 1024 |
-rtrace `vwrays -d -vf view1.vf -x 1024 -y 1024` -ffc scene.oct > view1.pic
+vwrays \-ff \-vf view1.vf \-x 1024 \-y 1024 |
+rtrace `vwrays \-d \-vf view1.vf \-x 1024 \-y 1024` \-ffc scene.oct > view1.hdr
 .SH AUTHOR
 Greg Ward Larson
 .SH ACKNOWLEDGMENT
@@ -125,4 +149,4 @@ can reproduce any pixel ordering (i.e., any image orie
 a rendered picture, it will only produce standard scanline-ordered rays when 
 given a set of view parameters.
 .SH "SEE ALSO"
-rcalc(1), rpict(1), rtrace(1)
+rcalc(1), rcode_depth(1), rcontrib(1), rpict(1), rtpict(1), rtrace(1)