man/man1/ranimove.1

.\" RCSid "$Id: ranimove.1,v 1.8 2012/09/28 22:20:49 greg Exp $"
.TH RANIMOVE 1 1/30/03 RADIANCE
.SH NAME
ranimove - render a RADIANCE animation with motion
.SH SYNOPSIS
.B ranimove
[
.B \-s
][
.B \-e
][
.B \-w
][
.B "\-f beg,end"
][
.B "\-n nprocs"
][
.B "\-t sec"
][
.B "\-d jnd"
]
.B rnmfile
.SH DESCRIPTION
.I Ranimove
is a program for progressive animation rendering.
Variables in the given
.I rnmfile
indicate input files, output file names,
and various other controls and options.
.PP
Normally, progress reports are written to the standard output, but the
.I \-s
option tells
.I ranimove
to do its work silently.
The
.I \-e
option tells
.I ranimove
to explicate all variables used for the animation, including
default values not specified in the input file, and print them on
the standard output.
The
.I \-w
option turns off warnings about multiply and misassigned variables and
non-fatal rendering problems.
.PP
Normally,
.I ranimove
will produce one animation frame for each view given in the specified
view file.
If the
.I \-f
option is specified, the animation will resume at the given frame, and
continue to the end of the sequence, or to the second frame if one is given
(separated from the first by a comma but no space).
.PP
The
.I \-n
option specifies the number of processes to use for rendering.
The default value is 1, which is appropriate for most machines
that have a single central processing unit (CPU).
If you are running on a machine with multiple CPUs, a larger
value up to the number of processors may be used
to improve rendering speed, depending on the system load.
.PP
Because
.I ranimove
renders each frame progressively, it needs some criteria for when
to proceed to the next frame in the animation.
The
.I \-t
option is used to specify the maximum number of seconds to spend
on any one frame.
The default value for this option is 60 seconds.
Additionally, the
.I \-d
option may be used to specify a termination
threshold in just-noticeable-differences.
If the error can be reduced below this number of JNDs
over the whole frame before the time allocation is spent,
.I ranimove
will then proceed to the next frame.
A value of 2.0 JNDs is the point at which 75% of the people will notice
a difference, and this is the level usually selected for such a
termination test.
There is no default value for this option, which means that rendering
will proceed until the time allocation is spent for each frame, regardless.
If
.I \-t
is set to 0,
.I ranimove
will spend as much time as it takes to reduce the
visible error below the value set by the
.I \-d
option.
.PP
.I Ranimove
renders each frame in three stages.
In the first stage, a low-quality image
is rendered using one ray sample per 16 pixels.
In the second stage, pixels from the previous frame are extrapolated to
their corresponding positions in
this one, based on the given camera and object movements.
A set of heuristics is applied
to prevent errors in specular highlights and shadows, avoiding
some of the errors typical with the
.I pinterp(1)
program.
In the third stage, additional high-quality samples are used to refine
important regions of the image that are judged to have visible errors.
This proceeds until the stopping criteria specified by the
.I \-t
and
.I -d
options are met,
when the frame is filtered and written to the designated picture file.
.PP
The chief differences between this program and
.I ranimate(1)
are that motion blur is computed for objects as well as camera movement,
and its progressive rendering allows better control over the tradeoff
between frame accuracy and rendering time.
Fewer controls are provided for managing the picture files produced by
.I ranimove,
and no facilities for distributed rendering are available other
than executing
.I ranimove
on different machines using the
.I \-f
option to manually partition the work.
.PP
Animation variable assignments appear one per line in
.I rnmfile.
The name of the variable is followed by an equals sign
('=') and its value(s).
The end of line may be escaped with a backslash ('\\'), though it is
not usually necessary since additional variable values may be given
in multiple assignments.
Variables that should have only one value are given in upper case.
Variables that may have multiple values are given in lower case.
Variables may be abbreviated by their first three letters.
Comments in
.I rnmfile
start with a pound sign ('#') and proceed to the end of line.
.PP
The animation variables, their interpretations and default values
are given below.
.TP 10n
.BR OCTREE
The name of the base octree file, which should be generated by the
.I oconv(1)
command using the
.I \-f
option.
There is no default value for this variable.
If no
.I RIF
variable is given, the octree must be specified.
.TP
.BR RIF
This variable specifies a
.I rad(1)
input file to use as a source of rendering options and other
variable settings.
If given,
.I ranimate
will execute
.I rad
and create an options file to control rendering parameters.
.I Ranimate
will also extract default settings for the common variables:
.I OCTREE,
.I RESOLUTION,
and
.I EXPOSURE.
Following the file name, overriding variable settings may be given,
which will be passed to
.I rad
on the command line.
Settings with spaces in them should be enclosed in quotes.
The execution of
.I rad
will also update the contents of the octree, if necessary.
There is no default value for this variable.
.TP
.BR move
This variable specifies an object (or objects) with a specific
motion and/or rendering priority.
Four value arguments are expected for each appearance of this variable.
The first is the name of a parent move object, or "void" if none.
If given, the object's transformation will be prepended to that
of its parent.
The second argument is the name of this object, which will be used
to name surfaces it contains, and as a parent identifier for any child
objects that reference it.
The third argument is the transformation string or file for this object.
If this argument is enclosed in quotes and begins with a hyphen
('-'), then it will be interpreted as a
static transform specification a la
.I xform(1).
Otherwise, the argument will be taken as the name of a file that contains
one such transform specification per line, corresponding to frames in the
animation.
A period ('.') may be given if no object transformation is desired.
The fourth argument is the name of a
.I RADIANCE
scene file (or files) to be given to
.I xform
for transformation.
If this argument begins with an exclamation point ('!'), then
it will be interpreted as a command rather than a file.
A final word corresponding to the frame number will be
appended to the command, and its output will be passed to
the input of
.I xform
for each frame.
An optional fifth argument
specifies the rendering priority for this object.
Values greater than 1.0 will result in preferential rendering of
this object over other portions of the image when it appears in a frame.
Values less than 1.0 will cause the rendering to neglect this object in
favor of other parts of the image.
A value of 3.0 can be interpreted as saying the viewer is three times more
likely to look at this object than the background.
A file may be given rather than a floating point value, and this file must
contain one floating point number per line, corresponding to priorities
for frames in the animation.
.TP
.BR VIEWFILE
This variable names a file from which
.I ranimove
may extract the view for each frame in the animation.
This file should contain one valid view per frame, starting with
frame 1 on line 1.
An exception is made for a view file with only a single view, which
is used for every frame of the animation.
In this case, the
.I END
variable must also be specified.
This variable is required, and there is no default value.
.TP
.BR END
The final frame number in the animation.
The default value is computed from the number of views in the given
.I VIEWFILE.
Normally, this variable will only be given if the view is static.
.TP
.BR EXPOSURE
This variable tells
.I ranimate
how to adjust the exposure for each frame.
As in
.I pfilt,
the exposure setting may be given either as a multiplier or as a
number of f\-stop adjustments (eg. +2 or \-1.5).
Alternatively, a file name may be given, which
.I ranimate
will interpret as having one exposure value per line per frame,
beginning with frame 1 at line 1.
(See also the
.I VIEWFILE
variable, above.)\0
There is no default value for this variable.
If it is not given, no exposure adjustments will be made.
.TP
.BR BASENAME
The base output file name for the final frames.
This string should contain a
.I printf(3)
style integer field to distinguish one frame number from another.
The final frames will use this name with a ".hdr" suffix.
The default value is "frame%03d".
.TP
.BR MBLUR
This variable specifies the fraction of a frame time that the shutter
is simulated as being open for motion blur.
Motion blur is computed by
.I ranimove
using image-based rendering methods in a rather crude fashion.
A much better result is achieved by setting
.I MBLUR=0
and using the
.I pmblur2(1)
command as a post-process, assigning the
.I ZNAME
and
.I MNAME
variables described below.
The default motion blur is 0.
.TP
.BR RATE
This variable specifies the animation frame rate, in frames per second.
This is needed to compute the animation error visibility.
The default value is 8.
.TP
.BR RESOLUTION
This variable specifies the desired final picture resolution.
If only a single number is given, this value will be used for both
the horizontal and vertical picture dimensions.
If two numbers are given, the first is the horizontal resolution and
the second is the vertical resolution.
If three numbers are given, the third is taken as the pixel aspect
ratio for the final picture (a real value).
If the pixel aspect ratio is zero, the exact dimensions given will
be those produced.
Otherwise, they will be used as a frame in which the final image
must fit.
The default value for this variable is 640.
.TP
.BR lowq
This variable may be used to specify rendering options
for the initial, low-quality ray samples.
It may be given either as a list of rendering parameter settings,
or as variable settings for the
.I rad
command, in which case the
.I RIF
variable must also be specified.
.TP
.BR highq
This variable may be used to specify rendering options
for the final, high-quality ray samples.
It may be given either as a list of rendering parameter settings,
or as variable settings for the
.I rad
command, in which case the
.I RIF
variable must also be specified.
.TP
.BR oconv
This variable may be used to specify special options for
.I oconv.
See the
.I oconv(1)
manual page for a list of valid options.
(The
.I \-f
option is specified by default.)\0
.TP
.BR ZNAME
The base file name for the depth buffer output frames.
This string should contain a
.I printf(3)
style integer field to distinguish one frame number from another.
The final frames will use this name with a ".zbf" suffix.
This is needed by the
.I pmblur2
command to compute a better motion blur.
There is no default setting for this variable.
.TP
.BR MNAME
The base file name for the motion vector output frames.
This string should contain a
.I printf(3)
style integer field to distinguish one frame number from another.
The final frames will use this name with a ".mvo" suffix.
This file is used together with the image and depth buffer by
.I pmblur2
to compute a better motion blur.
In this case, the
.I MBLUR
variable should be unset or zero.
The file will contain 3 16-bit unsigned values per pixel.
The first two are the x and y offsets to each pixel in the previous frame,
with an offset of 32768 being no movement.
The third value is 0 if the previous frame's pixel was on a
different object, and 32768 if it was on the same object.
There is no default setting for this variable.
.SH EXAMPLES
A minimal input file for
.I ranimove
might look like this:
.IP "" .3i
.nf
::::::::::
sample.rnm
::::::::::
# The rad input file for our static scene:
RIF= tutor.rif
# The view file containing one view per frame:
VIEWFILE= anim1.vf
# Our central character and its motion:
move= void myguy myguy.xf myguy.rad 2.0
.fi
.PP
Note that most of the variables are not set in this file.
If we only want to see what default values
.I ranimove
would use without actually executing anything, we can invoke it
thus:
.IP "" .2i
ranimove \-n 0 \-e sample.rnm
.PP
This will print the variables we have given as well as default
values
.I ranimove
has assigned for us.
.PP
Usually, we execute
.I ranimove
in the background, redirecting the standard output and standard
error to a file:
.IP "" .2i
ranimove sample.rnm >& sample.err &
.PP
If we decide that the default values
.I ranimove
has chosen for our variables are not all appropriate, we can add
some more assignments to the file:
.IP "" .3i
.nf
RES= 1024                               # shoot for 1024x resolution
MBLUR= .25                              # apply camera motion blur
RATE= 15                                # 15 frames/second
EXP= anim1.exp                          # adjust exposure according to file
lowq= QUAL=Low                          # low quality ray sampling
highq= QUAL=Med                         # high quality ray sampling
.fi
.PP
Note the use of abbreviation for variable names.
.SH AUTHOR
Greg Ward
.SH "SEE ALSO"
fieldcomb(1), oconv(1), pfilt(1), pinterp(1), pmblur2(1), pvalue(1), rad(1),
ran2tiff(1), ranimate(1), rpict(1), xform(1)
Revision:	1.9
Committed:	Fri Oct 5 00:59:38 2012 UTC (11 years, 8 months ago) by greg
Branch:	MAIN
CVS Tags:	rad5R4, rad5R2, rad4R2P2, rad5R0, rad5R1, rad4R2, rad4R2P1, rad5R3, HEAD
Changes since 1.8:	+24 -10 lines
Log Message:	Created pmblur2 command to compute better motion blur from ranimove runs
#	User	Rev	Content
1	greg	1.9	.\" RCSid "$Id: ranimove.1,v 1.8 2012/09/28 22:20:49 greg Exp $"
2	greg	1.2	.TH RANIMOVE 1 1/30/03 RADIANCE
3	greg	1.1	.SH NAME
4			ranimove - render a RADIANCE animation with motion
5			.SH SYNOPSIS
6			.B ranimove
7			[
8			.B \-s
9			][
10			.B \-e
11			][
12			.B \-w
13			][
14			.B "\-f beg,end"
15			][
16			.B "\-n nprocs"
17			][
18			.B "\-t sec"
19			][
20			.B "\-d jnd"
21			]
22			.B rnmfile
23			.SH DESCRIPTION
24			.I Ranimove
25			is a program for progressive animation rendering.
26			Variables in the given
27			.I rnmfile
28			indicate input files, output file names,
29			and various other controls and options.
30			.PP
31			Normally, progress reports are written to the standard output, but the
32			.I \-s
33			option tells
34			.I ranimove
35			to do its work silently.
36			The
37			.I \-e
38			option tells
39			.I ranimove
40			to explicate all variables used for the animation, including
41			default values not specified in the input file, and print them on
42			the standard output.
43			The
44			.I \-w
45			option turns off warnings about multiply and misassigned variables and
46			non-fatal rendering problems.
47			.PP
48			Normally,
49			.I ranimove
50			will produce one animation frame for each view given in the specified
51			view file.
52			If the
53			.I \-f
54			option is specified, the animation will resume at the given frame, and
55			continue to the end of the sequence, or to the second frame if one is given
56			(separated from the first by a comma but no space).
57			.PP
58			The
59			.I \-n
60			option specifies the number of processes to use for rendering.
61			The default value is 1, which is appropriate for most machines
62			that have a single central processing unit (CPU).
63			If you are running on a machine with multiple CPUs, a larger
64			value up to the number of processors may be used
65			to improve rendering speed, depending on the system load.
66			.PP
67			Because
68			.I ranimove
69			renders each frame progressively, it needs some criteria for when
70			to proceed to the next frame in the animation.
71			The
72			.I \-t
73			option is used to specify the maximum number of seconds to spend
74			on any one frame.
75			The default value for this option is 60 seconds.
76			Additionally, the
77			.I \-d
78			option may be used to specify a termination
79			threshold in just-noticeable-differences.
80			If the error can be reduced below this number of JNDs
81			over the whole frame before the time allocation is spent,
82			.I ranimove
83			will then proceed to the next frame.
84			A value of 2.0 JNDs is the point at which 75% of the people will notice
85			a difference, and this is the level usually selected for such a
86			termination test.
87			There is no default value for this option, which means that rendering
88			will proceed until the time allocation is spent for each frame, regardless.
89			If
90			.I \-t
91			is set to 0,
92			.I ranimove
93			will spend as much time as it takes to reduce the
94			visible error below the value set by the
95			.I \-d
96			option.
97			.PP
98			.I Ranimove
99			renders each frame in three stages.
100			In the first stage, a low-quality image
101			is rendered using one ray sample per 16 pixels.
102			In the second stage, pixels from the previous frame are extrapolated to
103			their corresponding positions in
104			this one, based on the given camera and object movements.
105			A set of heuristics is applied
106			to prevent errors in specular highlights and shadows, avoiding
107			some of the errors typical with the
108			.I pinterp(1)
109			program.
110			In the third stage, additional high-quality samples are used to refine
111			important regions of the image that are judged to have visible errors.
112			This proceeds until the stopping criteria specified by the
113			.I \-t
114			and
115			.I -d
116			options are met,
117			when the frame is filtered and written to the designated picture file.
118			.PP
119			The chief differences between this program and
120			.I ranimate(1)
121			are that motion blur is computed for objects as well as camera movement,
122			and its progressive rendering allows better control over the tradeoff
123			between frame accuracy and rendering time.
124			Fewer controls are provided for managing the picture files produced by
125			.I ranimove,
126			and no facilities for distributed rendering are available other
127			than executing
128			.I ranimove
129			on different machines using the
130			.I \-f
131			option to manually partition the work.
132			.PP
133			Animation variable assignments appear one per line in
134			.I rnmfile.
135			The name of the variable is followed by an equals sign
136			('=') and its value(s).
137			The end of line may be escaped with a backslash ('\\'), though it is
138			not usually necessary since additional variable values may be given
139			in multiple assignments.
140			Variables that should have only one value are given in upper case.
141			Variables that may have multiple values are given in lower case.
142			Variables may be abbreviated by their first three letters.
143			Comments in
144			.I rnmfile
145			start with a pound sign ('#') and proceed to the end of line.
146			.PP
147			The animation variables, their interpretations and default values
148			are given below.
149			.TP 10n
150			.BR OCTREE
151			The name of the base octree file, which should be generated by the
152			.I oconv(1)
153			command using the
154			.I \-f
155			option.
156			There is no default value for this variable.
157			If no
158			.I RIF
159			variable is given, the octree must be specified.
160			.TP
161			.BR RIF
162			This variable specifies a
163			.I rad(1)
164			input file to use as a source of rendering options and other
165			variable settings.
166			If given,
167			.I ranimate
168			will execute
169			.I rad
170			and create an options file to control rendering parameters.
171			.I Ranimate
172			will also extract default settings for the common variables:
173			.I OCTREE,
174			.I RESOLUTION,
175			and
176			.I EXPOSURE.
177			Following the file name, overriding variable settings may be given,
178			which will be passed to
179			.I rad
180			on the command line.
181			Settings with spaces in them should be enclosed in quotes.
182			The execution of
183			.I rad
184			will also update the contents of the octree, if necessary.
185			There is no default value for this variable.
186			.TP
187			.BR move
188			This variable specifies an object (or objects) with a specific
189			motion and/or rendering priority.
190			Four value arguments are expected for each appearance of this variable.
191			The first is the name of a parent move object, or "void" if none.
192			If given, the object's transformation will be prepended to that
193			of its parent.
194			The second argument is the name of this object, which will be used
195	greg	1.7	to name surfaces it contains, and as a parent identifier for any child
196			objects that reference it.
197	greg	1.1	The third argument is the transformation string or file for this object.
198			If this argument is enclosed in quotes and begins with a hyphen
199			('-'), then it will be interpreted as a
200			static transform specification a la
201			.I xform(1).
202			Otherwise, the argument will be taken as the name of a file that contains
203			one such transform specification per line, corresponding to frames in the
204			animation.
205			A period ('.') may be given if no object transformation is desired.
206			The fourth argument is the name of a
207			.I RADIANCE
208			scene file (or files) to be given to
209			.I xform
210			for transformation.
211			If this argument begins with an exclamation point ('!'), then
212			it will be interpreted as a command rather than a file.
213			A final word corresponding to the frame number will be
214			appended to the command, and its output will be passed to
215			the input of
216			.I xform
217			for each frame.
218	greg	1.7	An optional fifth argument
219	greg	1.1	specifies the rendering priority for this object.
220	greg	1.7	Values greater than 1.0 will result in preferential rendering of
221	greg	1.1	this object over other portions of the image when it appears in a frame.
222	greg	1.7	Values less than 1.0 will cause the rendering to neglect this object in
223	greg	1.1	favor of other parts of the image.
224			A value of 3.0 can be interpreted as saying the viewer is three times more
225			likely to look at this object than the background.
226			A file may be given rather than a floating point value, and this file must
227	greg	1.7	contain one floating point number per line, corresponding to priorities
228			for frames in the animation.
229	greg	1.1	.TP
230			.BR VIEWFILE
231			This variable names a file from which
232			.I ranimove
233			may extract the view for each frame in the animation.
234			This file should contain one valid view per frame, starting with
235			frame 1 on line 1.
236			An exception is made for a view file with only a single view, which
237			is used for every frame of the animation.
238			In this case, the
239			.I END
240			variable must also be specified.
241			This variable is required, and there is no default value.
242			.TP
243			.BR END
244			The final frame number in the animation.
245			The default value is computed from the number of views in the given
246			.I VIEWFILE.
247			Normally, this variable will only be given if the view is static.
248			.TP
249			.BR EXPOSURE
250			This variable tells
251			.I ranimate
252			how to adjust the exposure for each frame.
253			As in
254			.I pfilt,
255			the exposure setting may be given either as a multiplier or as a
256	greg	1.5	number of f\-stop adjustments (eg. +2 or \-1.5).
257	greg	1.1	Alternatively, a file name may be given, which
258			.I ranimate
259			will interpret as having one exposure value per line per frame,
260			beginning with frame 1 at line 1.
261			(See also the
262			.I VIEWFILE
263			variable, above.)\0
264			There is no default value for this variable.
265			If it is not given, no exposure adjustments will be made.
266			.TP
267			.BR BASENAME
268			The base output file name for the final frames.
269			This string should contain a
270			.I printf(3)
271			style integer field to distinguish one frame number from another.
272	greg	1.6	The final frames will use this name with a ".hdr" suffix.
273	greg	1.1	The default value is "frame%03d".
274			.TP
275			.BR MBLUR
276			This variable specifies the fraction of a frame time that the shutter
277			is simulated as being open for motion blur.
278			Motion blur is computed by
279			.I ranimove
280	greg	1.9	using image-based rendering methods in a rather crude fashion.
281			A much better result is achieved by setting
282			.I MBLUR=0
283			and using the
284			.I pmblur2(1)
285			command as a post-process, assigning the
286			.I ZNAME
287			and
288			.I MNAME
289			variables described below.
290			The default motion blur is 0.
291	greg	1.1	.TP
292			.BR RATE
293			This variable specifies the animation frame rate, in frames per second.
294			This is needed to compute the animation error visibility.
295			The default value is 8.
296			.TP
297			.BR RESOLUTION
298			This variable specifies the desired final picture resolution.
299			If only a single number is given, this value will be used for both
300			the horizontal and vertical picture dimensions.
301			If two numbers are given, the first is the horizontal resolution and
302			the second is the vertical resolution.
303			If three numbers are given, the third is taken as the pixel aspect
304			ratio for the final picture (a real value).
305			If the pixel aspect ratio is zero, the exact dimensions given will
306			be those produced.
307			Otherwise, they will be used as a frame in which the final image
308			must fit.
309			The default value for this variable is 640.
310			.TP
311			.BR lowq
312			This variable may be used to specify rendering options
313			for the initial, low-quality ray samples.
314			It may be given either as a list of rendering parameter settings,
315			or as variable settings for the
316			.I rad
317			command, in which case the
318			.I RIF
319			variable must also be specified.
320			.TP
321			.BR highq
322			This variable may be used to specify rendering options
323			for the final, high-quality ray samples.
324			It may be given either as a list of rendering parameter settings,
325			or as variable settings for the
326			.I rad
327			command, in which case the
328			.I RIF
329			variable must also be specified.
330			.TP
331			.BR oconv
332			This variable may be used to specify special options for
333			.I oconv.
334			See the
335			.I oconv(1)
336			manual page for a list of valid options.
337			(The
338			.I \-f
339			option is specified by default.)\0
340	greg	1.8	.TP
341			.BR ZNAME
342			The base file name for the depth buffer output frames.
343			This string should contain a
344			.I printf(3)
345			style integer field to distinguish one frame number from another.
346			The final frames will use this name with a ".zbf" suffix.
347	greg	1.9	This is needed by the
348			.I pmblur2
349			command to compute a better motion blur.
350	greg	1.8	There is no default setting for this variable.
351			.TP
352			.BR MNAME
353			The base file name for the motion vector output frames.
354			This string should contain a
355			.I printf(3)
356			style integer field to distinguish one frame number from another.
357			The final frames will use this name with a ".mvo" suffix.
358	greg	1.9	This file is used together with the image and depth buffer by
359			.I pmblur2
360			to compute a better motion blur.
361			In this case, the
362			.I MBLUR
363			variable should be unset or zero.
364	greg	1.8	The file will contain 3 16-bit unsigned values per pixel.
365	greg	1.9	The first two are the x and y offsets to each pixel in the previous frame,
366			with an offset of 32768 being no movement.
367	greg	1.8	The third value is 0 if the previous frame's pixel was on a
368			different object, and 32768 if it was on the same object.
369			There is no default setting for this variable.
370	greg	1.1	.SH EXAMPLES
371			A minimal input file for
372			.I ranimove
373			might look like this:
374			.IP "" .3i
375			.nf
376			::::::::::
377			sample.rnm
378			::::::::::
379			# The rad input file for our static scene:
380			RIF= tutor.rif
381			# The view file containing one view per frame:
382			VIEWFILE= anim1.vf
383			# Our central character and its motion:
384			move= void myguy myguy.xf myguy.rad 2.0
385			.fi
386			.PP
387			Note that most of the variables are not set in this file.
388			If we only want to see what default values
389			.I ranimove
390			would use without actually executing anything, we can invoke it
391			thus:
392			.IP "" .2i
393	greg	1.5	ranimove \-n 0 \-e sample.rnm
394	greg	1.1	.PP
395			This will print the variables we have given as well as default
396			values
397			.I ranimove
398			has assigned for us.
399			.PP
400			Usually, we execute
401			.I ranimove
402			in the background, redirecting the standard output and standard
403			error to a file:
404			.IP "" .2i
405			ranimove sample.rnm >& sample.err &
406			.PP
407			If we decide that the default values
408			.I ranimove
409			has chosen for our variables are not all appropriate, we can add
410			some more assignments to the file:
411			.IP "" .3i
412			.nf
413			RES= 1024 # shoot for 1024x resolution
414			MBLUR= .25 # apply camera motion blur
415			RATE= 15 # 15 frames/second
416			EXP= anim1.exp # adjust exposure according to file
417			lowq= QUAL=Low # low quality ray sampling
418			highq= QUAL=Med # high quality ray sampling
419			.fi
420			.PP
421			Note the use of abbreviation for variable names.
422			.SH AUTHOR
423			Greg Ward
424			.SH "SEE ALSO"
425	greg	1.9	fieldcomb(1), oconv(1), pfilt(1), pinterp(1), pmblur2(1), pvalue(1), rad(1),
426	greg	1.4	ran2tiff(1), ranimate(1), rpict(1), xform(1)