What makes MGF special?
There are three principal reasons to use MGF as an input language for lighting simulation and physically-based rendering: • It’s the only existing format that describes materials physically. • It is endorsed by the Illuminating Engineering Society of North America (IESNA) as part of their LM-63-1995 standard for luminaire data. • It’s easy and fun to support since it comes with a standard parser and sample scenes and objects at the web site, http://radsite.lbl.gov/mgf/HOME.html. The standard parser provides both immediate and long-term benefits, since it presents a programming interface that is more stable even than the language itself. Unlike AutoCAD DXF and other de facto standards, a change to the language will not break existing programs. This is because the parser gives the calling software only those entities it can handle. If the translator understands only polygons, it will be given only polygons. If a new geometric primitive is included in a later version of the standard, the
