[ViewVC] Diff of: Development/ray/doc/man/man1/rtrace.1

Comparing ray/doc/man/man1/rtrace.1 (file contents):
Revision 1.21 by greg, Sun Sep 26 15:49:39 2010 UTC vs.
Revision 1.26 by greg, Tue Feb 24 19:39:26 2015 UTC

+If the direction vector is (0,0,0), a bogus record
+is printed and the output is flushed if the
+.I -x
-<
+value is unset or zero.
->
+value is one or zero.
+(See the notes on this option below.)\0
+This may be useful for programs that run
+.I rtrace
+.I \-i
+option.
+.TP
-<
+.BI -sj \ frac
-<
+Set the specular sampling jitter to
-<
+.I frac.
-<
+This is the degree to which the highlights are sampled
-<
+for rough specular materials.
-<
+A value of one means that all highlights will be fully sampled
-<
+using distributed ray tracing.
->
+.BI -ss \ samp
->
+Set the specular sampling to
->
+.I samp.
->
+For values less than 1, this is the degree to which the highlights
->
+are sampled for rough specular materials.
->
+A value greater than one causes multiple ray samples to be sent
->
+to reduce noise at a commmesurate cost.
+A value of zero means that no jittering will take place, and all
+reflections will appear sharp even when they should be diffuse.
+.TP
+.TP
+.BR -bv
+Boolean switch for back face visibility.
-<
+With this switch off, back faces of opaque objects will be invisible
-<
+to all rays.
->
+With this switch off, back faces of all objects will be invisible
->
+to view rays.
+This is dangerous unless the model was constructed such that
-<
+all surface normals on opaque objects face outward.
->
+all surface normals face outward.
+Although turning off back face visibility does not save much
+computation time under most circumstances, it may be useful as a
+tool for scene debugging, or for seeing through one-sided walls from
+the outside.
-–
+This option has no effect on transparent or translucent materials.
+.TP
+.BI -av " red grn blu"
+Set the ambient value to a radiance of
+.BI -ab \ N
+Set the number of ambient bounces to
+.I N.
-<
+This is the maximum number of diffuse bounces
-<
+computed by the indirect calculation.
-<
+A value of zero implies no indirect calculation.
->
+This is the maximum number of diffuse bounces computed by the indirect
->
+calculation. A value of zero implies no indirect calculation.
->
+.IP
->
+In photon mapping mode (see
->
+.I -ap
->
+below), a positive value implies that global photon irradiance is
->
+always computed via
->
+.I one
->
+ambient bounce. A negative value enables a preview mode that directly
->
+visualises the irradiance from the global photon map without any ambient
->
+bounces.
+.TP
+.BI -ar \ res
+Set the ambient resolution to
+except read modifiers to be included from
+.I file.
+.TP
-+
+.BI -ap " file [bwidth1 [bwidth2]]"
-+
+Enable photon mapping mode. Loads a photon map generated with
-+
+.I mkpmap(1)
-+
+from
-+
+.I file,
-+
+and evaluates the indirect irradiance depending on the photon type
-+
+(automagically detected) using density estimates with a bandwidth of
-+
+.I bwidth1
-+
+photons, or the default bandwidth if none is specified (a warning will be
-+
+issued in this case).
-+
+.IP
-+
+Global photon irradiance is evaluated as part of the ambient calculation (see
-+
+.I \-ab
-+
+above), caustic photon irradiance is evaluated at primary rays, and
-+
+indirect inscattering in
-+
+.I mist
-+
+is accounted for by volume photons.
-+
+.IP
-+
+Additionally specifying
-+
+.I bwidth2
-+
+enables bias compensation for the density estimates with a
-+
+minimum and maximum bandwidth of
-+
+.I bwidth1
-+
+and
-+
+.I bwidth2,
-+
+respectively.
-+
+.IP
-+
+Global photon irradiance may be optionally precomputed by
-+
+.I mkpmap(1),
-+
+in which case the bandwidth, if specified, is ignored, as the nearest photon
-+
+is invariably looked up.
-+
+.IP
-+
+Using direct photons replaces the direct calculation with density estimates
-+
+for debugging and validation of photon emission.
-+
+.TP
-+
+.BI -am " frac"
-+
+Coefficient for maximum search radius for photon map lookups. The search
-+
+radius is automatically determined based on the average photon distance to the
-+
+distribution's centre of gravity, and scaled by this coefficient. Increase this
-+
+value if multiple warnings about short photon lookups are issued.
-+
+.TP
+.BI -me " rext gext bext"
+Set the global medium extinction coefficient to the indicated color,
+in units of 1/distance (distance in world coordinates).
+on most multiprocessing platforms, since the
+.I fork(2)
+system call will share memory on a copy-on-write basis.
-+
+.SH NOTES
-+
+Photons are generally surface bound (an exception are volume photons), thus
-+
+the ambient irradiance in photon mapping mode will be biased at positions
-+
+which do not lie on a surface.
+.SH EXAMPLES
+To compute radiance values for the rays listed in samples.inp:
+.IP "" .2i
+.IP "" .2i
+cnt 480 640 | rcalc \-e 'xr:640;yr:480' \-f unusual_view.cal | rtrace
+\-x 640 \-y 480 \-fac scene.oct > unusual.hdr
-+
+.PP
-+
+To compute ambient illuminance in photon mapping mode from a global photon
-+
+map global.pm via one ambient bounce, and from a caustic photon map
-+
+caustic.pm at sensor positions in samples.inp:
-+
+.IP "" .2i
-+
+rtrace -h -ov -ab 1 -ap global.pm 50 -ap caustic.pm 50 scene.oct <
-+
+samples.inp > illum.out
+.SH ENVIRONMENT
+RAYPATH         the directories to check for auxiliary files.
+.SH FILES
+.SH AUTHOR
+Greg Ward
+.SH "SEE ALSO"
-<
+getinfo(1), lookamb(1), oconv(1), pfilt(1), pinterp(1),
-<
+pvalue(1), rpict(1), rtcontrib(1), rvu(1), vwrays(1), ximage(1)
->
+getinfo(1), lookamb(1), mkpmap(1), oconv(1), pfilt(1), pinterp(1),
->
+pvalue(1), rpict(1), rcontrib(1), rvu(1), vwrays(1), ximage(1)

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Comparing ray/doc/man/man1/rtrace.1 (file contents): Revision 1.21 by greg, Sun Sep 26 15:49:39 2010 UTC vs. Revision 1.26 by greg, Tue Feb 24 19:39:26 2015 UTC

Diff Legend

Comparing ray/doc/man/man1/rtrace.1 (file contents):
Revision 1.21 by greg, Sun Sep 26 15:49:39 2010 UTC vs.
Revision 1.26 by greg, Tue Feb 24 19:39:26 2015 UTC