/usr/share/radiance/tilt.cal is in radiance-materials 4R1+20120125-1.1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 | { RCSid: $Id: tilt.cal,v 2.3 2003/02/22 02:07:23 greg Exp $ }
{
tilt.cal - tilt data for IES luminaires
}
tilt_ang = Acos(Kz) / DEGREE;
tilt_xang = if(Jy*Jy-FTINY, Asin(Jy/sqrt(Jy*Jy+Jz*Jz))/DEGREE, 0);
tilt_ang2 = tri(tilt_ang, 90);
tilt_xang2 = tri(tilt_xang, 90);
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