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Comparing ray/doc/man/man1/rtrace.1 (file contents):
Revision 1.2 by greg, Fri Apr 18 17:29:21 2003 UTC vs.
Revision 1.19 by greg, Sun Dec 13 19:13:03 2009 UTC

# Line 1 | Line 1
1 < .\" RCSid "$Id"
1 > .\" RCSid "$Id$"
2   .TH RTRACE 1 10/17/97 RADIANCE
3   .SH NAME
4   rtrace - trace rays in RADIANCE scene
# Line 87 | Line 87 | d      direction (normalized)
87   .IP
88   v       value (radiance)
89   .IP
90 + V       contribution (radiance)
91 + .IP
92   w       weight
93   .IP
94 + W       color coefficient
95 + .IP
96   l       effective length of ray
97   .IP
98   L       first intersection distance
# Line 105 | Line 109 | s      surface name
109   .IP
110   m       modifier name
111   .IP
112 + M       material name
113 + .IP
114 + ~       tilde (end of trace marker)
115 + .IP
116   If the letter 't' appears in
117   .I spec,
118   then the fields following will be printed for every ray traced,
119   not just the final result.
120 + If the capital letter 'T' is given instead of 't', then all rays will
121 + be reported, including shadow testing rays to light sources.
122   Spawned rays are indented one tab for each level.
123 + The tilde marker ('~') is a handy way of differentiating the final ray
124 + value from daughter values in a traced ray tree, and usually appears
125 + right before the 't' or 'T' output flags.
126 + E.g.,
127 + .I \-ov~TmW
128 + will emit a tilde followed by a tab at the end of each trace,
129 + which can be easily distinguished even in binary output.
130   .IP
131   Note that there is no space between this option and its argument.
132   .TP
133 < .BI -te \ mat
133 > .BI -te \ mod
134   Append
135 < .I mat
135 > .I mod
136   to the trace exclude list,
137   so that it will not be reported by the trace option
138   .I (\-o*t*).
139   Any ray striking an object having
140 < .I mat
140 > .I mod
141   as its modifier will not be reported to the standard output with
142   the rest of the rays being traced.
143 < This option has no effect unless the 't' option has been given as
144 < part of the output specifier.
145 < Any number of excluded materials may be given, but each
143 > This option has no effect unless either the 't' or 'T'
144 > option has been given as part of the output specifier.
145 > Any number of excluded modifiers may be given, but each
146   must appear in a separate option.
147   .TP
148 < .BI -ti \ mat
148 > .BI -ti \ mod
149   Add
150 < .I mat
150 > .I mod
151   to the trace include list,
152 < so that it will be considered during the indirect calculation.
152 > so that it will be reported by the trace option.
153   The program can use either an include list or an exclude
154   list, but not both.
155   .TP
156   .BI -tE \ file
157   Same as
158   .I \-te,
159 < except read materials to be excluded from
159 > except read modifiers to be excluded from
160   .I file.
161   The RAYPATH environment variable determines which directories are
162   searched for this file.
163 < The material names are separated by white space in the file.
163 > The modifier names are separated by white space in the file.
164   .TP
165   .BI -tI \ file
166   Same as
167   .I \-ti,
168 < except read materials to be included from
168 > except read modifiers to be included from
169   .I file.
170   .TP
171   .BR \-i
# Line 163 | Line 180 | option (below) may be used to override this.
180   This option is especially useful in
181   conjunction with ximage(1) for computing illuminance at scene points.
182   .TP
183 + .BR \-u
184 + Boolean switch to control uncorrelated random sampling.
185 + When "off", a low-discrepancy sequence is used, which reduces
186 + variance but can result in a brushed appearance in specular highlights.
187 + When "on", pure Monte Carlo sampling is used in all calculations.
188 + .TP
189   .BR \-I
190   Boolean switch to compute irradiance rather than radiance,
191   with the input origin and direction interpreted instead
# Line 207 | Line 230 | format.
230   .I \-f
231   option, above.)
232   .TP
233 + .BI -n \ nproc
234 + Execute in parallel on
235 + .I nproc
236 + local processes.
237 + This option is incompatible with the
238 + .I \-P
239 + and
240 + .I \-PP,
241 + options.
242 + Multiple processes also do not work properly with ray tree output
243 + using any of the
244 + .I \-o*t*
245 + options.
246 + There is no benefit from specifying more processes than there are
247 + cores available on the system or the
248 + .I \-x
249 + setting, which forces a wait at each flush.
250 + .TP
251   .BI -dj \ frac
252   Set the direct jittering to
253   .I frac.
# Line 427 | Line 468 | header of the ambient file.
468   .I Getinfo(1)
469   may be used to print out this information.
470   .TP
471 < .BI -ae \ mat
471 > .BI -ae \ mod
472   Append
473 < .I mat
473 > .I mod
474   to the ambient exclude list,
475   so that it will not be considered during the indirect calculation.
476   This is a hack for speeding the indirect computation by
477   ignoring certain objects.
478   Any object having
479 < .I mat
479 > .I mod
480   as its modifier will get the default ambient
481   level rather than a calculated value.
482 < Any number of excluded materials may be given, but each
482 > Any number of excluded modifiers may be given, but each
483   must appear in a separate option.
484   .TP
485 < .BI -ai \ mat
485 > .BI -ai \ mod
486   Add
487 < .I mat
487 > .I mod
488   to the ambient include list,
489   so that it will be considered during the indirect calculation.
490   The program can use either an include list or an exclude
# Line 452 | Line 493 | list, but not both.
493   .BI -aE \ file
494   Same as
495   .I \-ae,
496 < except read materials to be excluded from
496 > except read modifiers to be excluded from
497   .I file.
498   The RAYPATH environment variable determines which directories are
499   searched for this file.
500 < The material names are separated by white space in the file.
500 > The modifier names are separated by white space in the file.
501   .TP
502   .BI -aI \ file
503   Same as
504   .I \-ai,
505 < except read materials to be included from
505 > except read modifiers to be included from
506   .I file.
507   .TP
508   .BI -me " rext gext bext"
# Line 503 | Line 544 | source within a given scattering volume.
544   .BI -lr \ N
545   Limit reflections to a maximum of
546   .I N.
547 + If
548 + .I N
549 + is zero or negative, then Russian roulette is used for ray
550 + termination, and the
551 + .I -lw
552 + setting (below) must be positive.
553 + If N is a negative integer, then this sets the upper limit
554 + of reflections past which Russian roulette will not be used.
555 + In scenes with dielectrics and total internal reflection,
556 + a setting of 0 (no limit) may cause a stack overflow.
557   .TP
558   .BI -lw \ frac
559   Limit the weight of each ray to a minimum of
560   .I frac.
561 < During ray-tracing, a record is kept of the final contribution
562 < a ray would have to the image.
563 < If it is less then the specified minimum, the ray is not traced.
561 > During ray-tracing, a record is kept of the estimated contribution
562 > (weight) a ray would have in the image.
563 > If this weight is less than the specified minimum and the
564 > .I -lr
565 > setting (above) is positive, the ray is not traced.
566 > Otherwise, Russian roulette is used to
567 > continue rays with a probability equal to the ray weight
568 > divided by the given
569 > .I frac.
570   .TP
571   .BR -ld
572   Boolean switch to limit ray distance.
# Line 573 | Line 630 | system call will share memory on a copy-on-write basis
630   .SH EXAMPLES
631   To compute radiance values for the rays listed in samples.inp:
632   .IP "" .2i
633 < rtrace -ov scene.oct < samples.inp > radiance.out
633 > rtrace \-ov scene.oct < samples.inp > radiance.out
634   .PP
635   To compute illuminance values at locations selected with the 't'
636   command of
637   .I ximage(1):
638   .IP "" .2i
639 < ximage scene.pic | rtrace -h -x 1 -i scene.oct | rcalc -e '$1=47.4*$1+120*$2+11.6*$3'
639 > ximage scene.hdr | rtrace \-h \-x 1 \-i scene.oct | rcalc \-e '$1=47.4*$1+120*$2+11.6*$3'
640   .PP
641   To record the object identifier corresponding to each pixel in an image:
642   .IP "" .2i
643 < vwrays -fd scene.pic | rtrace -fda `vwrays -d scene.pic` -os scene.oct
643 > vwrays \-fd scene.hdr | rtrace \-fda `vwrays \-d scene.hdr` \-os scene.oct
644   .PP
645   To compute an image with an unusual view mapping:
646   .IP "" .2i
647 < cnt 640 480 | rcalc -e 'xr:640;yr:480' -f unusual_view.cal | rtrace
648 < -x 640 -y 480 -fac scene.oct > unusual.pic
647 > cnt 480 640 | rcalc \-e 'xr:640;yr:480' \-f unusual_view.cal | rtrace
648 > \-x 640 \-y 480 \-fac scene.oct > unusual.hdr
649   .SH ENVIRONMENT
650   RAYPATH         the directories to check for auxiliary files.
651   .SH FILES
652 < /usr/tmp/rtXXXXXX               common header information for picture sequence
652 > /tmp/rtXXXXXX           common header information for picture sequence
653   .SH DIAGNOSTICS
654   If the program terminates from an input related error, the exit status
655   will be 1.
# Line 607 | Line 664 | option.
664   Greg Ward
665   .SH "SEE ALSO"
666   getinfo(1), lookamb(1), oconv(1), pfilt(1), pinterp(1),
667 < pvalue(1), rpict(1), rview(1), vwrays(1), ximage(1)
667 > pvalue(1), rpict(1), rtcontrib(1), rvu(1), vwrays(1), ximage(1)

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