STLB Files
Stereolithography (binary)
These are some examples of STLB, or "binary STL" files. "STL" stands for
"stereolithography", and indicates that the primary purpose of this
file format is to describe the shape of a 3D stationary object.
Stereolithography is a means of creating physical 3D models of
such objects, using resin or carefully cut and joined pieces of paper.
A binary STL file usually has a filename extension of ".stl".
It contains a description of the surface of a solid that has been
decomposed into triangles. The vertices of the triangles should
be listed in counterclockwise order, as viewed from outside the surface.
A normal vector for the triangle may also be listed.
The file begins with a solid record, (which can include a name
for the object), and ends with an endsolid record. Each
triangle begins with a facet record and ends with an
endfacet record. The normal vector, if given, is included as
part of the facet record, and is identified by the normal
keyword. The normal vector should have unit length. The three vertices
of the triangle are delimited by outer loop and endloop
records. Each vertex is described on a vertex record that
lists its (X,Y,Z) coordinates.
A binary STL file has the following structure:
-
An 80 byte ASCII header that can be used as a title.
-
A 4 byte unsigned long integer, the number of facets.
-
For each facet, a facet record of 50 bytes.
The facet record has the form:
-
The normal vector, 3 floating values of 4 bytes each;
-
Vertex 1 XYZ coordinates, 3 floating values of 4 bytes each;
-
Vertex 2 XYZ coordinates, 3 floating values of 4 bytes each;
-
Vertex 3 XYZ coordinates, 3 floating values of 4 bytes each;
-
An unsigned integer, of 2 bytes, that should be zero;
Binary STL File Characteristics:
-
binary
-
No color information
-
3D
-
No compression
-
1 image
Related Data and Programs:
For debugging, or small examples, it is an ASCII
stereolithography file format is available.
For information, see
the STLA format.
Reference:
-
3D Systems, Inc,
Stereolithography Interface Specification,
October 1989.
Programs to create a binary STL file:
-
MATHEMATICA has an Export command that can output graphics
files in STL format.
Programs to convert a binary STL file to another format:
-
The C++ program
IVCON
can read in an STLB file and write it out in a variety of 3D formats.
-
The FORTRAN90 program
IVREAD
can read in an STLB file and write it out in a variety of 3D formats.
-
The Visual Toolkit
routine vtkSTLReader can read an STL binary file.
Programs to convert another format to binary STL format:
-
The C++ program
IVCON
can read a variety of 3D files and write them out in STLB format.
-
The FORTRAN90 program
IVREAD
can read a variety of 3D files and write them out in STLB format.
-
The Visual Toolkit
routine vtkSTLWriter can write a VTK image to an
STL binary file.
Programs to write a binary STL file:
-
MATHEMATICA
includes an Export[filename,object] command
that can save a 3D graphics object as a binary STL file.
Programs to view a binary STL file:
-
PARAVIEW is a 3D graphics program which can read binary STL files and
display the data. The home page for PARAVIEW is
http://www.paraview.org/ .
Sample Files:
You can go up one level to
the DATA page.
Last revised on 18 September 2005.