Universidad de Oviedo, 33006-Oviedo, Spain

*Combining chemistry, free computer graphics and a little art
to make high-quality molecular graphics.*

- Program short description
- Program examples
- Browse the html documentation
- Download Source code (see the ascii version documentation in the file tessel.doc): tar.gz version (170348 Bytes) , zip version (212704 Bytes) .
- Download HTML documentation: tar.gz version (518769 Bytes) , zip version (562839 Bytes) .
- Old versions: tessel 1.0 , tessel 2.0 source (160 KB) and documentation (520 KB) .

Tessel2 is a 3D "compiler" to produce crystal and molecular models, parametric surfaces and several forms of sphere tesselations.

Molecular models combine balls-and-sticks, arrows and coordination polyhedra representations of pure and defective crystals, finite molecules or clusters. The Madelung potential of an ionic system can be computed and depicted on an arbitrary plane or surface. The common crystallographic cell (parallepipedic), as well as the Wigner-Seitz cell or the irreducible components of the WS cell can be easily added to the plot.

Parametric surfaces are defined by means of analytical expressions and several space mappings can be used (i.e. cartesian, spherical coordinates, etc).

Several methods for tesselating the sphere are currently implemented, including: recursively subdividing a inscribed cube, tetrahedron or octahedron; geodesic division based on a number of meridians and parallels; and minimization of the electrostatic repulsion of a set of points lying on the sphere surface.

The program produces output to be rendered with POV-Ray 2 or 3, Geomview (OFF format), or any Virtual Reality renderer (VRML V1.0 format). In addition, a very simple output (POINTS) is provided for those applications in which a list of points is best suited.

Examples of images created with tessel and rendered with either POV-Ray 2.2 or Geomview . Click on each image to see a large rendering of the same plot as well as the tessel input.

Examine this example of a tessel input file:

# Plot of a explicit cartesian function z = f(x,y) parametric uname x vname y urange -1 1 21 vrange -1 1 21 c1 x c2 y c3 sin(2*pi*x)+sin(2*pi*x) off tessel.off povray tessel.pov endparametric run povray +ft +Itessel.pov +Otessel.tga +W100 +H100 end |

Go to the html documentation page.

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