GENKLEMSAMP(1)						      General Commands Manual						    GENKLEMSAMP(1)

NAME

       genklemsamp - generate ray samples over surfaces using Klems BSDF basis

SYNOPSIS

       genklemsamp [ -c N ][ -f{a|f|d} ] [ view opts ] [ geom.rad ..  ]

DESCRIPTION

       Genklemsamp generates ray origins and directions to sample planar surfaces needed to determine incident radiances or daylight coefficients.
       This command is typically used in conjunction with rtcontrib(1) to analyze exterior daylight coefficients for an annual simulation.

       The view options are needed to specify (at minimum) the view direction, which corresponds to the orientation of the surfaces, and the  view
       up  vector,  which corresponds to the azimuth=90-degree position on the Klems sampling hemisphere.  The view fore clipping distance is also
       quite useful, as it provides a means to pass through some thickness in a fenestration system before  samples  are  sent	out.   Other  view
       options such as the view type and aft clipping distance are overridden or ignored.

       If  no Radiance scene files are provided, then the specified parallel view defines the width, height, center, and orientation of the window
       or facade of interest.  If one or more scene files are given, they are presumed to contain planar  surfaces  over  which  genklemsamp  will
       originate  samples.   The  sampled  surface  normals  must  correspond to the specified view direction, and unaligned surfaces are silently
       ignored.

       The -c option specifies the number of rays to sample per Klems direction.  These samples will be distributed evenly  over  the  surface(s).
       The default setting is 1000.

       The  -ff  option  specifies  that output rays should be generated as 32-bit IEEE binary float values.  This may be more efficient if passed
       directly to rtcontrib or rtrace(1) with the same option.  Likewise, the -fd option specifies 64-bit IEEE binary double values.  The default
       setting of -fa produces ASCII floating point values.

EXAMPLE

       To  generate  500  samples  per	direction  over  a set of south-facing windows and pass to rtcontrib to compute daylight coefficients in a
       matrix:

	 genklemsamp -c 500 -vd 0 -1 0 -vu 0 0 1 south_windows.rad | rtcontrib -c 500 -e MF:1 -f reinhart.cal -b rbin -bn  Nrbins  exterior.oct  >
	 Dsouth.dat

AUTHOR

       Greg Ward

SEE ALSO

       dctimestep(1), genBSDF(1), genskyvec(1), mkillum(1), rtcontrib(1), rtrace(1), vwrays(1)

RADIANCE
							      6/13/09							    GENKLEMSAMP(1)