| 142 |
|
|
| 143 |
|
.IP "\fB\-aps \fImod\fR" |
| 144 |
|
Specifies a modifier \fImod\fR defined as \fIantimatter\fR material to act |
| 145 |
< |
as a dummy (i.e. invisible) sensor surface. Photons will be deposited on |
| 145 |
> |
as a virtual (i.e. invisible) receiver surface. Photons will be deposited on |
| 146 |
|
all surfaces using this modifier, just like regular materials, but will then |
| 147 |
|
be transferred through the surface without undergoing scattering; the |
| 148 |
|
surface therefore does not affect the light transport and simply acts as an |
| 156 |
|
an error if the specified modifier is not an \fIantimatter\fR material. |
| 157 |
|
|
| 158 |
|
.IP "\fB\-apS \fImodfile\fR" |
| 159 |
< |
Read dummy sensor surface modifiers from the file \fImodfile\fR as a more |
| 159 |
> |
Read virtual receiver surface modifiers from the file \fImodfile\fR as a more |
| 160 |
|
convenient alternative to multiple instances of \fB\-aps\fR. |
| 161 |
|
|
| 162 |
|
.IP "\fB\-bv\fR[\fB+\fR|\fB-\fR]" |
| 207 |
|
Set the global scattering eccentricity for participating media in conjunction |
| 208 |
|
with the \fB\-apv\fR option. See \fIrpict(1)\fR for details. |
| 209 |
|
|
| 210 |
+ |
.IP "\fB\-n \fInproc\fR" |
| 211 |
+ |
Use \fInproc\fR processes for parallel photon distribution. There is no |
| 212 |
+ |
benefit in specifying more than the number of physical CPU cores available. |
| 213 |
+ |
|
| 214 |
|
.IP "\fB\-t \fIinterval\fR" |
| 215 |
|
Output a progress report every \fIinterval\fR seconds. This includes |
| 216 |
|
statistics about the currently emitting light source (including number of |
| 256 |
|
disabled with the photon map, as the resulting caustics are already accounted |
| 257 |
|
for. |
| 258 |
|
|
| 259 |
< |
.SS Dummy Sensor Surfaces |
| 259 |
> |
.SS Virtual Receiver Surfaces |
| 260 |
|
Since photons are surface bound, the density estimate is only asymptotically |
| 261 |
|
correct when performed at points which lie on the scene geometry. The |
| 262 |
|
irradiance is underestimated for arbitrarily placed points when photons are |
| 263 |
|
collected from distant surfaces. \fIMkpmap\fR offers a workaround with a |
| 264 |
< |
dummy sensor surface using the \fIantimatter\fR material; see the \fB-aps\fR |
| 264 |
> |
virtual receiver surface using the \fIantimatter\fR material; see the \fB-aps\fR |
| 265 |
|
and \fB-apS\fR options for details. |
| 266 |
|
|
| 267 |
|
.SH EXAMPLES |
