| 2 |
|
.TH PMAPDUMP 1 "$Date$ $Revision$" RADIANCE |
| 3 |
|
|
| 4 |
|
.SH NAME |
| 5 |
< |
pmapdump - generate RADIANCE scene description of photon map distribution |
| 5 |
> |
pmapdump - generate RADIANCE scene description or point list representing |
| 6 |
> |
photon positions and (optionally) flux |
| 7 |
|
|
| 8 |
|
.SH SYNOPSIS |
| 9 |
< |
pmapdump [\fB-n\fR \fInspheres1\fR] [\fB-r\fR \fIradscale1\fR] \fIpmap1\fR |
| 10 |
< |
[\fB-n\fR \fInspheres2\fR] [\fB-r\fR \fIradscale2\fR] \fIpmap2\fR ... |
| 9 |
> |
pmapdump [\fB-a\fR] [\fB-n\fR \fInum1\fR] [\fB-r\fR \fIradscale1\fR] |
| 10 |
> |
[\fB-f\fR | \fB-c\fR \fIrcol1\fR \fIgcol1\fR \fIbcol1\fR] |
| 11 |
> |
\fIpmap1\fR |
| 12 |
> |
[\fB-a\fR] [\fB-n\fR \fInum2\fR] [\fB-r\fR \fIradscale2\fR] |
| 13 |
> |
[\fB-f\fR | \fB-c\fR \fIrcol2\fR \fIgcol2\fR \fIbcol2\fR] |
| 14 |
> |
\fIpmap2\fR ... |
| 15 |
|
|
| 16 |
|
.SH DESCRIPTION |
| 17 |
|
\fIpmapdump\fR takes one or more photon map files generated with |
| 18 |
< |
\fImkpmap(1)\fR as input and sends a RADIANCE scene description of their |
| 19 |
< |
photon distributions to the standard output. This can be visualised with |
| 20 |
< |
e.g. \fIobjview(1)\fR, \fIrpict(1)\fR, or \fIrvu(1)\fR to assess the |
| 21 |
< |
location and local density of photons in relation to the scene geometry. |
| 18 |
> |
\fImkpmap(1)\fR as input and, by default, sends a RADIANCE scene description |
| 19 |
> |
of their photon distributions to the standard output. Photons are |
| 20 |
> |
represented as spheres of material type \fIglow\fR. These can be |
| 21 |
> |
visualised with e.g. \fIobjview(1)\fR, \fIrpict(1)\fR, or \fIrvu(1)\fR to |
| 22 |
> |
assess the location and local density of photons in relation to the scene |
| 23 |
> |
geometry. No additional light sources are necessary, as the spheres |
| 24 |
> |
representing the photons are self-luminous. |
| 25 |
|
.PP |
| 26 |
+ |
Alternatively, photons can also be output as an ASCII point list, where |
| 27 |
+ |
each line contains a photon's position and colour. |
| 28 |
+ |
This point list can be imported in a 3D point cloud processor/viewer |
| 29 |
+ |
to interactively explore the photon map. |
| 30 |
+ |
.PP |
| 31 |
|
An arbitrary number of photon maps can be specified on the command line and |
| 32 |
< |
the respective photon type is determined automagically. The different |
| 33 |
< |
photon types are visualised as colour coded spheres according to the |
| 34 |
< |
following schema: |
| 32 |
> |
the respective photon type is determined automagically. Per default, the |
| 33 |
> |
different photon types are visualised as colour coded spheres/points |
| 34 |
> |
according to the following default schema: |
| 35 |
|
.IP |
| 36 |
|
\fIBlue\fR: global photons |
| 37 |
|
.br |
| 44 |
|
\fIMagenta\fR: direct photons |
| 45 |
|
.br |
| 46 |
|
\fIYellow\fR: contribution photons |
| 47 |
+ |
.PP |
| 48 |
+ |
These colours can be overridden for individual photon maps with the \fB-c\fR |
| 49 |
+ |
option (see below). Alternatively, photons can be individually coloured |
| 50 |
+ |
according to their actual RGB flux with the \fB-f\fR option (see below); |
| 51 |
+ |
while this makes it difficult to discern photon types, it can be used to |
| 52 |
+ |
quantitatively analyse colour bleeding effects, for example. |
| 53 |
|
|
| 54 |
|
.SH OPTIONS |
| 55 |
|
Options are effective for the photon map file immediately following on the |
| 56 |
|
command line, and are reset to their defaults after completion of each dump. |
| 57 |
< |
As such they may be set individually for each photon map. |
| 57 |
> |
As such they must be set individually for each photon map. |
| 58 |
|
|
| 59 |
< |
.IP "\fB-n \fInspheres\fR" |
| 60 |
< |
Specifies the number of spheres to dump for the next photon map. The dump |
| 61 |
< |
is performed by random sampling with \fInspheres\fR as target count, hence |
| 62 |
< |
the number actually output will be approximate. \fINspheres\fR may be |
| 63 |
< |
followed by a multiplier suffix for convenience, where \fIk\fR = 10^3 and |
| 64 |
< |
\fIm\fR = 10^6, although the latter may lead to problems when processing the |
| 65 |
< |
output geometry with \fIoconv(1)\fR. The default number of spheres is 10k. |
| 59 |
> |
.IP "\fB-a\fR" |
| 60 |
> |
Boolean switch to output photons as a point list in ASCII (text) format |
| 61 |
> |
instead of a RADIANCE scene. |
| 62 |
> |
Each output line consists of 6 tab-separated floating point values: the |
| 63 |
> |
X, Y, Z coordinates of the photon's position, and the R, G, B colour |
| 64 |
> |
channels of its flux. These values. notably the flux, are expressed in |
| 65 |
> |
scientific notation if necessary to accommodate their high dynamic range. |
| 66 |
|
|
| 67 |
+ |
.IP |
| 68 |
+ |
As \fIpmapdump\fR groups its options per photon map, this option must be |
| 69 |
+ |
specified per photon map for consistent output. This prevents erroneously |
| 70 |
+ |
dumping RADIANCE scene descriptions along with point lists, which will |
| 71 |
+ |
fail to load in the 3D point cloud viewer. |
| 72 |
+ |
|
| 73 |
+ |
.IP "\fB-c\fR \fIrcol\fR \fIgcol\fR \fIbcol\fR" |
| 74 |
+ |
Specifies a custom sphere/point colour for the next photon map. The colour |
| 75 |
+ |
is specified as an RGB triplet, with each component in the range (0..1]. |
| 76 |
+ |
Without this option, the default colour for the corresponding photon type |
| 77 |
+ |
is used. This option is mutually exclusive with \fB-f\fR. |
| 78 |
+ |
|
| 79 |
+ |
.IP "\fB-f\fR" |
| 80 |
+ |
Boolean switch to colour each sphere/point according to the corresponding |
| 81 |
+ |
photon's RGB flux instead of a constant colour. Note that no exposure is |
| 82 |
+ |
applied, and as such the resulting colours can span several orders of |
| 83 |
+ |
magnitude and may require tone mapping with \fIpcond(1)\fR for |
| 84 |
+ |
visualisation. This option is mutually exclusive with \fB-c\fR. |
| 85 |
+ |
|
| 86 |
+ |
.IP "\fB-n \fInum\fR" |
| 87 |
+ |
Specifies the number of spheres or points to dump for the next photon map. |
| 88 |
+ |
The dump is performed by random sampling with \fInum\fR as target count, |
| 89 |
+ |
hence the number actually output will be approximate. \fINum\fR may be |
| 90 |
+ |
suffixed by a case-insensitive multiplier for convenience, where |
| 91 |
+ |
\fIk\fR = 10^3 and \fIm\fR = 10^6, although the latter may lead to problems |
| 92 |
+ |
when processing the output geometry with \fIoconv(1)\fR. The default number |
| 93 |
+ |
is 10k. |
| 94 |
+ |
|
| 95 |
|
.IP "\fB-r \fIradscale\fR" |
| 96 |
|
Specifies a relative scale factor \fIradscale\fR for the sphere radius. The |
| 97 |
|
sphere radius is determined automatically from an estimated average distance |
| 98 |
|
between spheres so as to reduce clustering, assuming a uniform distribution. |
| 99 |
< |
In cases where the distribution is substantially nonuniform (e.g. highly |
| 99 |
> |
In cases where the distribution is substantially nonuniform (e.g. highly |
| 100 |
|
localised caustics) the radius can be manually corrected with this option. |
| 101 |
< |
The default value is 1.0. |
| 101 |
> |
The default value is 1.0. This option is ignored for point list output |
| 102 |
> |
in conjuction with \fB-a\fR. |
| 103 |
|
|
| 104 |
|
.SH NOTES |
| 105 |
< |
The output may contain many overlapping spheres in areas with high photon |
| 106 |
< |
density, particularly in caustics. This results in inefficient and slow |
| 107 |
< |
octree generation with \fIoconv(1)\fR. Generally this can be improved by |
| 108 |
< |
reducing \fInspheres\fR and/or \fIradscale\fR. |
| 105 |
> |
The RADIANCE scene output may contain many overlapping spheres in areas with |
| 106 |
> |
high photon density, particularly in caustics. This results in inefficient |
| 107 |
> |
and slow octree generation with \fIoconv(1)\fR. Generally this can be |
| 108 |
> |
improved by reducing \fInum\fR and/or \fIradscale\fR. |
| 109 |
|
|
| 110 |
|
.SH EXAMPLES |
| 111 |
< |
To visualise the distribution of global and caustic photons superimposed |
| 112 |
< |
on the scene geometry with 5000 and 10000 spheres, respectively: |
| 111 |
> |
Visualise the distribution of global and caustic photons superimposed |
| 112 |
> |
on the scene geometry with 5000 pale red and 10000 pale blue spheres, |
| 113 |
> |
respectively: |
| 114 |
|
.IP |
| 115 |
< |
pmapdump -n 5k global.pm -n 10k caustic.pm | |
| 116 |
< |
oconv - scene.rad > scene_pmdump.oct |
| 115 |
> |
pmapdump -n 5k -c 1 0.4 0.4 global.pm -n 10k -c 0.4 0.4 1 caustic.pm | |
| 116 |
> |
oconv - scene.rad > scene_pm.oct |
| 117 |
|
.PP |
| 118 |
< |
Alternatively, the dump may be viewed on its own by piping the output of |
| 119 |
< |
\fIpmapdump\fR directly into \fIobjview(1)\fR (using the default number of |
| 71 |
< |
spheres in this example): |
| 118 |
> |
Visualise the caustic photon distribution superimposed on the scene geometry |
| 119 |
> |
with 10000 spheres coloured according to the photons' respective RGB flux: |
| 120 |
|
.IP |
| 121 |
+ |
pmapdump -n 10k -f caustic.pm | oconv - scene.rad > scene_pm.oct |
| 122 |
+ |
.PP |
| 123 |
+ |
But Capt. B wants 'em bigger: |
| 124 |
+ |
.IP |
| 125 |
+ |
pmapdump -r 4.0 bonzo.pm > bonzo_bigballz.rad |
| 126 |
+ |
.PP |
| 127 |
+ |
RADIANCE scene dumps may also be viewed on their own by simply piping the |
| 128 |
+ |
output of \fIpmapdump\fR directly into \fIobjview(1)\fR (using the default |
| 129 |
+ |
number of spheres in this example): |
| 130 |
+ |
.IP |
| 131 |
|
pmapdump zombo.pm | objview |
| 132 |
+ |
.PP |
| 133 |
+ |
Instead of a RADIANCE scene, dump photons as a (really long) point list to |
| 134 |
+ |
an ASCII file for import into a 3D point cloud viewer: |
| 135 |
+ |
.IP |
| 136 |
+ |
pmapdump -a -f -n 1m lotsa.pm > lotsa_pointz.txt |
| 137 |
|
|
| 138 |
|
.SH AUTHOR |
| 139 |
|
Roland Schregle (roland.schregle@{hslu.ch,gmail.com}) |
| 145 |
|
.SH ACKNOWLEDGEMENT |
| 146 |
|
Development of the RADIANCE photon mapping extension was sponsored by the |
| 147 |
|
German Research Foundation (DFG) and the Swiss National Science Foundation |
| 148 |
< |
(SNF). |
| 148 |
> |
(SNF). Greetz to Capt. B! |
| 149 |
|
|
| 150 |
|
.SH "SEE ALSO" |
| 151 |
|
mkpmap(1), objview(1), oconv(1), rpict(1), rvu(1), |
| 152 |
< |
\fIThe RADIANCE Photon Map Manual\fR |
| 152 |
> |
\fIThe RADIANCE Photon Map Manual\fR, |
| 153 |
> |
\fIBonzo Daylighting Tool [TM]\fR |
| 154 |
> |
|
| 155 |
|
|
