87 |
|
.IP |
88 |
|
v value (radiance) |
89 |
|
.IP |
90 |
+ |
V contribution (radiance) |
91 |
+ |
.IP |
92 |
|
w weight |
93 |
|
.IP |
94 |
|
W color coefficient |
180 |
|
This option is especially useful in |
181 |
|
conjunction with ximage(1) for computing illuminance at scene points. |
182 |
|
.TP |
183 |
< |
.BR \-R |
184 |
< |
Boolean switch to control random sampling. |
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. |
612 |
|
.SH EXAMPLES |
613 |
|
To compute radiance values for the rays listed in samples.inp: |
614 |
|
.IP "" .2i |
615 |
< |
rtrace -ov scene.oct < samples.inp > radiance.out |
615 |
> |
rtrace \-ov scene.oct < samples.inp > radiance.out |
616 |
|
.PP |
617 |
|
To compute illuminance values at locations selected with the 't' |
618 |
|
command of |
619 |
|
.I ximage(1): |
620 |
|
.IP "" .2i |
621 |
< |
ximage scene.pic | rtrace -h -x 1 -i scene.oct | rcalc -e '$1=47.4*$1+120*$2+11.6*$3' |
621 |
> |
ximage scene.hdr | rtrace \-h \-x 1 \-i scene.oct | rcalc \-e '$1=47.4*$1+120*$2+11.6*$3' |
622 |
|
.PP |
623 |
|
To record the object identifier corresponding to each pixel in an image: |
624 |
|
.IP "" .2i |
625 |
< |
vwrays -fd scene.pic | rtrace -fda `vwrays -d scene.pic` -os scene.oct |
625 |
> |
vwrays \-fd scene.hdr | rtrace \-fda `vwrays \-d scene.hdr` \-os scene.oct |
626 |
|
.PP |
627 |
|
To compute an image with an unusual view mapping: |
628 |
|
.IP "" .2i |
629 |
< |
cnt 640 480 | rcalc -e 'xr:640;yr:480' -f unusual_view.cal | rtrace |
630 |
< |
-x 640 -y 480 -fac scene.oct > unusual.pic |
629 |
> |
cnt 640 480 | rcalc \-e 'xr:640;yr:480' \-f unusual_view.cal | rtrace |
630 |
> |
\-x 640 \-y 480 \-fac scene.oct > unusual.hdr |
631 |
|
.SH ENVIRONMENT |
632 |
|
RAYPATH the directories to check for auxiliary files. |
633 |
|
.SH FILES |