LTB Soft has announced LTB Light 9.0 (http://www.ltblight.com), an update of the US$299 Mac OS X application that permits natural and artificial lighting calculation with a color radiosity method applied to a finite elements plan.
Version 9.0 adds support for both metric and imperial units, as well as UNI EN 13201 tables. It also has some bug fixes.
LTB Light implements OpenGL. Data management take places through an internal CAD system, directly in a perspective view. It’s possible to introduce flatten surfaces with colored glazing, furniture, curved surfaces like cylinders, cones, ellipsoids, hyperboloids and complex objects like cross vaults. LTB Light is able to share information with other CADs through DXF and PICT files.
Light sources are totally managed inside the main program; it’s possible to import, show, modify and use the IESNA LM-63 photometric data files (ASCII text file commonly used by North American lighting fixture manufacturers) EULUMDAT (an European standard) and even PICT and DXF files (the program can convert a drawing in a photometry). Photometric data is modeled through 36 “C” (azimuth) curves and 181 “gamma” (zenith) angles; while lamp color is controlled by its color temperature or RGB color.
LTB Light works with Mac OS X 10.4 or higher. It’s Universal Binary so runs natively on both PowerPC and Intel Macs.