Standard Data Format of STL Reprinted from http://www.fabbers.com/tech/STL_Format Reprinted from Section 6.5 of Automated Fabrication by Marshall Burns, Ph.D. Technical source: StereoLithography Interface Specification, 3D Systems, Inc., October 1989 An STL (“StereoLithography”) file is a triangular representation of a 3-dimensional surface geometry. The surface is tessellated or broken down logically into a series of small triangles (facets). Each facet is described by a perpendicular direction and three points representing the vertices (corners) of the triangle. These data are used by a slicing algorithm to determine the cross sections of the 3-dimensional shape to be built by the fabber. Format Specifications An STL file consists of a list of facet data. Each facet is uniquely identified by a unit normal (a……

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Diamond structure Point set for diamond structure 0.00 0.00 0.00 0.50 0.50 0.00 1.00 1.00 0.00 0.25 0.25 0.25 0.75 0.75 0.25 0.50 0.00 0.50 1.00 0.50 0.50 0.50 1.00 0.50 0.00 0.50 0.50 0.75 0.25 0.75 0.25 0.75 0.75 1.00 0.00 1.00 0.50 0.50 1.00 0.00 1.00 1.00 The path Path1: 1,4,2,5,3 Path2: 5,8,11,9,4,6,10,7,5 Path3: 14,11,13,10,12 conn1: 3,5 conn2: 5,14 diamond_Points for one diamond unit Each diamond unit has 14 vertexes, of which 4 (4#, 5#, 10#, 11# in Table 1) are inside the cube, 6 (2#, 6#, 7#, 8#, 9#, 13#) are onto each surface of the cube, and the remaining 4 (1#, 3#, 12#, 14#) are at the vertexes of the cube (Fig 1). Fig 1. One diamond unit Table 1. Point-set for one diamond unit with $a=1$. 0.00 0.00 0.00 0.50 0.50 0.00 1.00 1.00 0.00……

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