| 208 |
|
There is no default value for this variable. |
| 209 |
|
.TP |
| 210 |
|
.BR section |
| 211 |
< |
A section is a 6-sided parallel prism given by an origin and three axis |
| 211 |
> |
A section is a parallelepiped given by an origin and three axis |
| 212 |
|
vectors (i.e., 12 floating point values in world coordinates). |
| 213 |
|
The axis vectors define the three edges attached to the origin vertex, |
| 214 |
|
and the other edges and vertices are determined by the parallel wall |
| 218 |
|
In object rendering mode, a section may instead contain a detailed |
| 219 |
|
object to be viewed from the outside. |
| 220 |
|
The grid dimensions for each axis may also be given by three additional |
| 221 |
< |
integer arguments following the prism axes. |
| 221 |
> |
integer arguments following the three axes. |
| 222 |
|
Otherwise, if the grid dimensions are left out or any are unspecified |
| 223 |
|
or zero, the "GRID" variable will be used to determine them from the |
| 224 |
|
section axis lengths. |
| 520 |
|
.IP "" .3i |
| 521 |
|
.nf |
| 522 |
|
RIF= sample.rif # rad input file |
| 523 |
< |
section= 2 2 4 5 0 0 0 7 0 0 0 3 # section prism boundaries |
| 523 |
> |
section= 2 2 4 5 0 0 0 7 0 0 0 3 # section parallelepiped origin & vectors |
| 524 |
|
.fi |
| 525 |
|
.PP |
| 526 |
|
Technically, the "RIF" setting is not necessary, but the results are |
