| 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 |
| 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 |
| 563 |
|
.I \-dv |
| 564 |
|
option (above) may be used to override this. |
| 565 |
|
.TP |
| 566 |
< |
.BR \-R |
| 567 |
< |
Boolean switch to control random sampling. |
| 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. |
| 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 |
