xenial (1) genskyvec.1.gz

NAME

       genskyvec - compute patch radiance averages for a specific sky

SYNOPSIS

       genskyvec [ -m N ][ -c r g b ]

DESCRIPTION

       Genskyvec  samples the Radinace sky description given on the standard input to generate a list of average
       patch radiances.  If there is a sun in the description, genskyvec will include its  contribution  in  the
       three nearest sky patches, distributing energy according to centroid proximity.

       By default, genskyvec divides the sky into 2305 patches, plus one patch for the ground.  This corresponds
       to Reinhart's extension of the Tregenza sky, where the  original  145  patches  are  subdivided  into  16
       subpatches, except at the zenith.  A different subdivision may be specified via the -m option.  The value
       given will be used to subdivide each dimension, so the default of  4  yields  almost  16  times  as  many
       patches  as  the  original  Tregenza  sky,  which can be specified with -m 1.  A higher resolution sky is
       generally better for daylight coefficient analysis where solar position is important.

       The -c option may be used to specify a color for the sky.  The gray  value  should  equal  1  for  proper
       energy balance The default sky color is -c 0.960 1.004 1.118 .

EXAMPLE

       To generate 578 patches corresponding to a 2x2 subdivision of the Tregenza sky on a sunny equinox noon:

         gensky 9 21 12 | genskyvec -m 2 > sky09_21_12.dat

AUTHOR

       Greg Ward

SEE ALSO

       dctimestep(1), genBSDF(1), gensky(1), gentregvec(1), rtcontrib(1), rtrace(1)