# MaterialAtom

NAME

    MaterialAtom - set material properties of atoms
    MaterialBond - set material properties of bonds
    MaterialDist - set material properties of distances
    MaterialPrim - set material properties of primitives
    MaterialInit - set initial material properties

SYNOPSIS

    MaterialAtom expr expr expr expr expr expr expr
    MaterialBond expr expr expr expr expr expr expr
    MaterialDist expr expr expr expr expr expr expr
    MaterialPrim expr expr expr expr expr expr expr
    MaterialInit expr expr expr expr expr expr expr

DESCRIPTION

The first four commands set the material properties of all selected atoms, bonds, distances or primitives. `MaterialInit` sets the initial material properties used for new objects.

The first three paramters give the coefficients for ambient, diffuse and specular reflection. These values should all be between 0 and 1, for good results the ambient and diffuse terms should sum up to around 1.

The fourth parameter gives the shininess, it only has an effect if the specular coefficient is not zero. Higher values for the shininess result in smaller specular highlights. Values can be from 1.0 (very dull) to 200 and more (highly polished metal).

The fifth parameter gives the reflection. 1.0 results in a complete reflection of other objects in the scene (mirror), 0.0 in no reflection.

The sixth parameter gives the opacity. 1.0 results in a completely opaque material, 0.0 in complete transparency.

The seventh parameter gives the index of refraction, it only has an influence for (partly) transparent materials. 1.0 gives no refraction, 1.5 is the value for glass, 2.4 for diamond.

Transparency is not supported on most hardware, and only to a limited amount on machines with high-end graphics. It is mainly useful for preparing files for ray tracing (`PlotPov`). Reflection is not supported on screen, it is only used for ray tracing.

Giving a value less than 0.0 for any value will not change it, this is useful for changing only part of the parameters.

EXAMPLES

    MaterialAtom 0.3 0.7 0.4 30 0.0 1.0 1.0

SEE ALSO

`Select*`, `Texture*`, `PlotPov`

DATE

991016