| 70 |
|
to the letter 'c'. |
| 71 |
|
This view is like a standard perspective vertically, but projected |
| 72 |
|
on a cylinder horizontally (like a soupcan's-eye view). |
| 73 |
< |
Two fisheye views are provided as well; 'h' yields a hemispherical fisheye |
| 74 |
< |
view and 'a' results in angular fisheye distortion. |
| 73 |
> |
Three fisheye views are provided as well; 'h' yields a hemispherical fisheye |
| 74 |
> |
view, 'a' results in angular fisheye distortion, and 's' |
| 75 |
> |
results in a planisphere (stereographic) projection. |
| 76 |
|
A hemispherical fisheye is a projection of the hemisphere onto a circle. |
| 77 |
|
The maximum view angle for this type is 180 degrees. |
| 78 |
|
An angular fisheye view is defined such that distance from the center of |
| 79 |
|
the image is proportional to the angle from the central view direction. |
| 80 |
|
An angular fisheye can display a full 360 degrees. |
| 81 |
+ |
A planisphere fisheye view maintains angular relationships between lines, |
| 82 |
+ |
and is commonly used for sun path analysis. |
| 83 |
+ |
This is more commonly known as a |
| 84 |
+ |
"stereographic projection," but we avoid the term here so as not to |
| 85 |
+ |
confuse it with a stereoscopic pair. |
| 86 |
+ |
A planisphere fisheye can display up to (but not including) 360 degrees, |
| 87 |
+ |
although distortion becomes extreme as this limit is approached. |
| 88 |
|
Note that there is no space between the view type |
| 89 |
|
option and its single letter argument. |
| 90 |
|
.TP |
| 97 |
|
.BI -vd " xd yd zd" |
| 98 |
|
Set the view direction vector to |
| 99 |
|
.I "xd yd zd". |
| 100 |
+ |
The length of this vector indicates the focal distance as needed by the |
| 101 |
+ |
.I \-pd |
| 102 |
+ |
option, described below. |
| 103 |
|
.TP |
| 104 |
|
.BI -vu " xd yd zd" |
| 105 |
|
Set the view up vector (vertical direction) to |
| 160 |
|
rendering an image a piece at a time. |
| 161 |
|
A value of 1 means that the rendered image starts just to the right of |
| 162 |
|
the normal view. |
| 163 |
< |
A value of -1 would be to the left. |
| 163 |
> |
A value of \-1 would be to the left. |
| 164 |
|
Larger or fractional values are permitted as well. |
| 165 |
|
.TP |
| 166 |
|
.BI -vl \ val |
| 271 |
|
.I frac |
| 272 |
|
is too large. |
| 273 |
|
It is usually wise to turn off image sampling when using |
| 274 |
< |
direct jitter by setting -ps to 1. |
| 274 |
> |
direct jitter by setting \-ps to 1. |
| 275 |
|
.TP |
| 276 |
|
.BI -ds \ frac |
| 277 |
|
Set the direct sampling ratio to |
| 480 |
|
.I Getinfo(1) |
| 481 |
|
may be used to print out this information. |
| 482 |
|
.TP |
| 483 |
< |
.BI -ae \ mat |
| 483 |
> |
.BI -ae \ mod |
| 484 |
|
Append |
| 485 |
< |
.I mat |
| 485 |
> |
.I mod |
| 486 |
|
to the ambient exclude list, |
| 487 |
|
so that it will not be considered during the indirect calculation. |
| 488 |
|
This is a hack for speeding the indirect computation by |
| 489 |
|
ignoring certain objects. |
| 490 |
|
Any object having |
| 491 |
< |
.I mat |
| 491 |
> |
.I mod |
| 492 |
|
as its modifier will get the default ambient |
| 493 |
|
level rather than a calculated value. |
| 494 |
< |
Any number of excluded materials may be given, but each |
| 494 |
> |
Any number of excluded modifiers may be given, but each |
| 495 |
|
must appear in a separate option. |
| 496 |
|
.TP |
| 497 |
< |
.BI -ai \ mat |
| 497 |
> |
.BI -ai \ mod |
| 498 |
|
Add |
| 499 |
< |
.I mat |
| 499 |
> |
.I mod |
| 500 |
|
to the ambient include list, |
| 501 |
|
so that it will be considered during the indirect calculation. |
| 502 |
|
The program can use either an include list or an exclude |
| 505 |
|
.BI -aE \ file |
| 506 |
|
Same as |
| 507 |
|
.I \-ae, |
| 508 |
< |
except read materials to be excluded from |
| 508 |
> |
except read modifiers to be excluded from |
| 509 |
|
.I file. |
| 510 |
|
The RAYPATH environment variable determines which directories are |
| 511 |
|
searched for this file. |
| 512 |
< |
The material names are separated by white space in the file. |
| 512 |
> |
The modifier names are separated by white space in the file. |
| 513 |
|
.TP |
| 514 |
|
.BI -aI \ file |
| 515 |
|
Same as |
| 516 |
|
.I \-ai, |
| 517 |
< |
except read materials to be included from |
| 517 |
> |
except read modifiers to be included from |
| 518 |
|
.I file. |
| 519 |
|
.TP |
| 520 |
|
.BI -me " rext gext bext" |
| 563 |
|
.I \-dv |
| 564 |
|
option (above) may be used to override this. |
| 565 |
|
.TP |
| 566 |
+ |
.BR \-u |
| 567 |
+ |
Boolean switch to control uncorrelated random sampling. |
| 568 |
+ |
When "off", a low-discrepancy sequence is used, which reduces |
| 569 |
+ |
variance but can result in a brushed appearance in specular highlights. |
| 570 |
+ |
When "on", pure Monte Carlo sampling is used in all calculations. |
| 571 |
+ |
.TP |
| 572 |
|
.BI -lr \ N |
| 573 |
|
Limit reflections to a maximum of |
| 574 |
|
.I N. |
| 575 |
+ |
If |
| 576 |
+ |
.I N |
| 577 |
+ |
is zero, then Russian roulette is used for ray |
| 578 |
+ |
termination, and the |
| 579 |
+ |
.I -lw |
| 580 |
+ |
setting (below) must be positive. |
| 581 |
+ |
If N is a negative integer, then this sets the upper limit |
| 582 |
+ |
of reflections past which Russian roulette will not be used. |
| 583 |
+ |
In scenes with dielectrics and total internal reflection, |
| 584 |
+ |
a setting of 0 (no limit) may cause a stack overflow. |
| 585 |
|
.TP |
| 586 |
|
.BI -lw \ frac |
| 587 |
|
Limit the weight of each ray to a minimum of |
| 588 |
|
.I frac. |
| 589 |
< |
During ray-tracing, a record is kept of the final contribution |
| 590 |
< |
a ray would have to the image. |
| 591 |
< |
If it is less then the specified minimum, the ray is not traced. |
| 589 |
> |
During ray-tracing, a record is kept of the estimated contribution |
| 590 |
> |
(weight) a ray would have in the image. |
| 591 |
> |
If this weight is less than the specified minimum and the |
| 592 |
> |
.I -lr |
| 593 |
> |
setting (above) is positive, the ray is not traced. |
| 594 |
> |
Otherwise, Russian roulette is used to |
| 595 |
> |
continue rays with a probability equal to the ray weight |
| 596 |
> |
divided by the given |
| 597 |
> |
.I frac. |
| 598 |
|
.TP |
| 599 |
|
.BI -S \ seqstart |
| 600 |
|
Instead of generating a single picture based only on the view |
| 782 |
|
A progress report writes the number of rays traced, the percentage |
| 783 |
|
completed, and the CPU usage to the standard error. |
| 784 |
|
Reports are given either automatically after the specified interval, |
| 785 |
< |
or when the process receives a continue (-CONT) signal (see |
| 785 |
> |
or when the process receives a continue (\-CONT) signal (see |
| 786 |
|
.I kill(1)). |
| 787 |
|
A value of zero turns automatic reporting off. |
| 788 |
|
.TP |
| 796 |
|
The default is to print warnings, so the first appearance of |
| 797 |
|
this option turns them off. |
| 798 |
|
.SH EXAMPLE |
| 799 |
< |
rpict -vp 10 5 3 -vd 1 -.5 0 scene.oct > scene.pic |
| 799 |
> |
rpict \-vp 10 5 3 \-vd 1 \-.5 0 scene.oct > scene.pic |
| 800 |
|
.PP |
| 801 |
< |
rpict -S 1 -o frame%02d.pic scene.oct < keyframes.vf |
| 801 |
> |
rpict \-S 1 \-o frame%02d.pic scene.oct < keyframes.vf |
| 802 |
|
.SH ENVIRONMENT |
| 803 |
|
RAYPATH the directories to check for auxiliary files. |
| 804 |
|
.SH FILES |
| 805 |
< |
/usr/tmp/rtXXXXXX common header information for picture sequence |
| 805 |
> |
/tmp/rtXXXXXX common header information for picture sequence |
| 806 |
|
.br |
| 807 |
|
rfXXXXXX temporary name for recover file |
| 808 |
|
.SH DIAGNOSTICS |
