Ubuntu Manpage: rvu - generate RADIANCE images interactively

Provided by: radiance_4R1+20120125-1.1_amd64

NAME

       rvu - generate RADIANCE images interactively

SYNOPSIS

       rvu [ rpict options ][ -n nproc ][ -o dev ][ -b ][ -pe exposure ] [ $EVAR ] [ @file ] octree
       rvu [ options ] -defaults
       rvu -devices

DESCRIPTION

Rvu generates RADIANCE images using octree. (The octree may be given as the output of a command enclosed
in quotes and preceded by a `!'.) Options specify the viewing parameters as well as giving some control
over the calculation. Options may be given on the command line and/or read from the environment and/or
read from a file. A command argument beginning with a dollar sign ('$') is immediately replaced by the
contents of the given environment variable. A command argument beginning with an at sign ('@') is
immediately replaced by the contents of the given file. The options are the same as for rpict(1), with a
few notable exceptions. The -r, -z, -S, -P, -PP and -t options are not supported, and -o specifies which
output device is being used instead of the output file. The -x, -y and -pa options are unnecessary,
since rvu scales the display image to the specified output device. Additionally, the -b option improves
the display on greyscale monitors, and -pe may be used to set an initial exposure value.

The -n option may be used to specify multiple processes, to accelerate rendering.

In the second form, the default values for the options are printed with a brief explanation. In the
third form, the list of supported output devices is displayed.

rvu starts rendering the image from the selected viewpoint and gradually improves the resolution of the
display until interrupted by keyboard input. rvu then issues a prompt (usually ':') and accepts a
command line from the user. rvu may also stop its calculation and wait for command input if the
resolution of the display has reached the resolution of the graphics device. At this point, it will give
the 'done:' prompt and await further instructions. If rvu runs out of memory due to lack of resources to
store its computed image, it will give the 'out of memory:' prompt. At this prompt, the user can save
the image, quit, or even restart a new image, although this is not generally recommended on virtual
memory machines for efficiency reasons.

rvu is not meant to be a rendering program, and we strongly recommend that rpict(1) be used instead for
that purpose. Since rpict(1) does not store its image in memory or update any display of its output, it
is much faster and less wasteful of its resources than rvu. rvu is intended as a quick interactive
program for deciding viewpoints and debugging scene descriptions and is not suited for producing polished
images.

COMMANDS

       Once the program starts, a number of commands can be used to control it.  A command is given by its name,
       which can be abbreviated, followed by its arguments.

       aim [ mag [ x y z ] ]
                 Zoom in by mag on point x y z .  The view point is held constant; only the view  direction  and
                 size  are  changed.   If  x  y  z  is missing, the cursor is used to select the view center.  A
                 negative magnification factor means zoom out.  The default factor is one.

       ^C        Interrupt.  Go to the command line.

       exposure [ spec ]
                 Adjust exposure.  The number spec is a multiplier used to compensate the average  exposure.   A
                 value  of  1  renormalizes the image to the computed average, which is usually done immediately
                 after startup.  If spec begins with a '+' or '-', the compensation is  interpreted  in  f-stops
                 (ie.  the power of two).  If spec begins with an '=', an absolute setting is performed.  An '='
                 by itself permits interactive display and setting of the exposure.  If spec begins with an '@',
                 the exposure is adjusted to present similar visibility to what would be experienced in the real
                 environment.  If spec is absent, or an '@' is followed by nothing, then the cursor is  used  to
                 pick a specific image location for normalization.

       focus [distance]
                 Set  focus distance for depth-of-field sampling.  If a distance in world coordinates is absent,
                 then the cursor is used to choose a point in the scene on which to focus.  (The focus  distance
                 setting  does  not  affect  rendering in rview, but can be used in rpict with the -pd option to
                 simulate depth-of-field on views saved from rview.)

       frame [ xmin ymin xmax ymax ]
                 Set frame for refinement.  If coordinates  are  absent,  the  cursor  is  used  to  pick  frame
                 boundaries.  If ``all'' is specified, the frame is reset to the entire image.

       free      Free  cached  object structures and associated data.  This command may be useful when memory is
                 low and a completely different view is being generated from the one previous.

       last [ file ]
                 Restore the previous view.  If a view or picture file is specified, the  parameters  are  taken
                 from the last view entry in the file.

       L [ vw [ rfile ] ]
                 Load parameters for view vw from the rad(1) input file, rfile.  Both vw and rfile must be given
                 the  first  call,  but  subsequent  calls  will use the last rfile as a default, and "1" as the
                 default view (ie. the first view appearing in rfile).  If rvu was  started  by  rad,  then  the
                 rfile parameter will initially default to the rad input file used.

       move [ mag [ x y z ] ]
                 Move  camera mag times closer to point x y z .  For a perspective projection (or fisheye view),
                 only the view point is changed; the view direction and size remain  constant.   The  view  size
                 must  be  modified  in  a  parallel  projection since it determines magnification.  If x y z is
                 missing, the cursor is used to  select  the  view  center.   A  negative  magnification  factor
                 decreases  the  object  size.   The  default factor is one.  Care must be taken to avoid moving
                 behind or inside other objects.

       new [ nproc ]
                 Restart the image, using the specified number of rendering processes.  Usually used  after  the
                 "set" command.

       pivot angle [ elev [ mag [ x y z ] ] ]
                 Similar  to  the  "move"  command,  but  pivots  the view about a selected point.  The angle is
                 measured in degrees around the view up vector using the right hand rule.  The optional elev  is
                 the  elevation in degrees from the pivot point; positive raises the view point to look downward
                 and negative lowers the view point to look upward.

       quit      Quit the program.

       ^R        Redraw the image.  Use when the  display  gets  corrupted.   On  some  displays,  occassionally
                 forcing  a redraw can improve appearance, as more color information is available and the driver
                 can make a better color table selection.

       rotate angle [ elev [ mag ] ]
                 Rotate the camera horizontally by angle degrees.  If an  elevation  is  specified,  the  camera
                 looks upward elev degrees.  (Negative means look downward.)

       set [ var [ val ] ]
                 Check/change program variable.  If var is absent, the list of available variables is displayed.
                 If  val  is  absent,  the current value of the variable is displayed and changed interactively.
                 Otherwise, the variable var assumes the value val.   Variables  include:  ambient  value  (av),
                 ambient value weight (aw), ambient bounces (ab), ambient accuracy (aa), ambient divisions (ad),
                 ambient  radius  (ar), ambient samples (as), black&white (b), back face visibility (bv), direct
                 jitter (dj), direct sampling (ds), direct threshold (dt), direct  visibility  (dv),  irradiance
                 (i),  limit  weight  (lw),  limit  recursion  (lr), medium extinction (me), medium albedo (ma),
                 medium eccentricity (mg), medium sampling  (ms),  pixel  sample  (ps),  pixel  threshold  (pt),
                 specular  jitter (sj), specular threshold (st), and uncorrelated sampling (u).  Once a variable
                 has been changed, the "new" command can be used to recompute the image with the new parameters.
                 If a program variable is not available here, it may show up under some other command or it  may
                 be impossible to change once the program is running.

       trace [ xbeg ybeg zbeg xdir ydir zdir ]
                 Trace a ray.  If the ray origin and direction are absent, the cursor is used to pick a location
                 in  the  image  to  trace.   The  object  intersected  and its material, location and value are
                 displayed.

       view [ file [ comments ] ]
                 Check/change view parameters.  If file is present, the view parameters are appended to a  file,
                 followed  by comments if any.  Alternatively, view options may be given directly on the command
                 line instead of an output view file.  Otherwise, view  parameters  are  displayed  and  changed
                 interactively.

       V [ vw [ rfile ] ]
                 Append  the current view as view vw in the rad file rfile.  Compliment to L command.  Note that
                 the view is simply appended to the file, and previous  views  with  the  same  name  should  be
                 removed before using the file with rad.

       write [ file ]
                 Write picture to file.  If argument is missing, the current file name is used.

       ^Z        Stop the program.  The screen will be redrawn when the program resumes.

ENVIRONMENT

       RAYPATH        the  directories  to  check for auxiliary files.  DISPLAY_GAMMA       the value to use for
       monitor gamma correction.

AUTHOR