LDraw
LDraw is a popular system of free software tools for modeling Lego creations in 3D on a computer. The LDraw file format and original program were written by James Jessiman. He also modeled many of the original parts in the parts library that is central to the programs and is under continuous maintenance and extension by the LDraw community. In 1997, Jessiman died. Since then, a variety of programs have been written that use the LDraw parts library, and file format. LDraw models are frequently rendered in POV-Ray, a free 3D ray tracer.
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