RSENSOR(1)						      General Commands Manual							RSENSOR(1)

NAME

       rsensor - compute sensor signal from a RADIANCE scene

SYNOPSIS

       rsensor [ -n nprocs ][ -h ][ render options ] [ $EVAR ] [ @file ] { [ -rd nrays ][ -dn nsrc ][ sensor_view ] sensor_file ..  } octree
       rsensor [ -h ] { [ -rd nrays ][ sensor_view ] sensor_file ..  } .
       rsensor [ options ] -defaults

DESCRIPTION

       Rsensor	traces	rays outward from one or more specified illumination sensors into the RADIANCE scene given by octree, sending the computed
       sensor value to the standard output.  (The octree may be given as the output of a command enclosed in quotes and preceded by  a	`!'.)	In
       the  second  form, a single period ('.') is given in place of an octree, and the origin and directions of the specified number of rays will
       be printed on the standard output.  If these rays are later traced and added together, the results will sum to a signal proportional to the
       given  sensor  distribution.   In the third form, the default values for the options (modified by those options present) are printed with a
       brief explanation.

       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 sensor files themselves will be searched for in the path locations specified by the RAYPATH	environment  variable,	similar  to  other
       types  of  Radiance  auxiliary  files.  If the sensor file path begins with '/', '.' or '~', no search will take place.	Before each sensor
       file, a separate view may be specified.	In this case, the view origin and direction will correspond to the position and orientation of the
       sensor,	and the view up vector will determine the zero azimuthal direction of the sensor.  The fore clipping distance may be used as well,
       but other view options will be ignored.	(See rpict(1) for details on how to specify a view.)  The actual data contained in the sensor file
       corresponds  to	the  SPOT  tab-separated  matrix  specification, where the column header has "degrees" in the leftmost column, followed by
       evenly-spaced azimuthal angles.	Each row begins with the polar angle, and is followed by the relative sensitivity values for  each  direc-
       tion.  A low-resolution example of a sensor file is given below:

	    degrees   0    90	180  270
	    0	 .02  .04  .02	.04
	    45	 .01  .02  .01	.02
	    90	 .001 .002 .001 .002

       As  well  as different views, the number of samples may be changed between sensors, where the -rd option controls the number of ray samples
       sent at random, and the -dn option controls the number of rays sent to each light source per sensor.

       The -h option toggles header output, which defaults to "on."  The -n option may be used to specify multiple calculation processes  on  sys-
       tems  with  more  than  one  CPU.  For additional options, consult the rtrace(1) man page.  The final octree argument must be given, as the
       octree cannot be read from the standard input.

EXAMPLES

       To compute values for the same sensor with two different positions:

	 rsensor -ab 2 -vf posA.vf mysens.dat -vf posB.vf mysens.dat scene.oct

       To generate a set of rays corresponding to a given sensor and compute the resulting signal with rtrace:

	 rsensor -h -vf posC.vf mysens.dat . | rtrace -h scene.oct | total -m

ENVIRONMENT

       RAYPATH	      the directories to check for auxiliary files.

AUTHOR

       Greg Ward for Architectural Energy Corporation

SEE ALSO

       oconv(1), rpict(1), rtcontrib(1), rtrace(1)

RADIANCE
							     4/11/2008								RSENSOR(1)