HP b2600 Reference Manual page 286

M
glMaterials
glMaterial takes three arguments. The first, face, specifies whether the GL_FRONT
materials, the GL_BACK materials, or both GL_FRONT_AND_BACK materials will be
modified. The second, pname, specifies which of several parameters in one or both sets
will be modified. The third, params, specifies what value or values will be assigned to the
specified parameter.
Material parameters are used in the lighting equation that is optionally applied to each
vertex. The equation is discussed in the glLightModel reference page. The parameters
that can be specified using glMaterial, and their interpretations by the lighting
equation, are as follows:
GL_AMBIENT
params contains four integer or floating-point values that specify the ambient RGBA
reflectance of the material. Integer values are mapped linearly such that the most
positive representable value maps to 1.0, and the most negative representable value
maps to - 1.0. Floating-point values are mapped directly. Neither integer nor
floating-point values are clamped. The initial ambient reflectance for both front- and
back-facing materials is (0.2, 0.2, 0.2, 1.0).
GL_DIFFUSE
params contains four integer or floating-point values that specify the diffuse RGBA
reflectance of the material. Integer values are mapped linearly such that the most
positive representable value maps to 1.0, and the most negative representable value
maps to - 1.0. Floating-point values are mapped directly. Neither integer nor
floating-point values are clamped. The initial diffuse reflectance for both front- and
back-facing materials is (0.8, 0.8, 0.8, 1.0).
GL_SPECULAR
params contains four integer or floating-point values that specify the specular RGBA
reflectance of the material. Integer values are mapped linearly such that the most
positive representable value maps to 1.0, and the most negative representable value
maps to - 1.0. Floating-point values are mapped directly. Neither integer nor
floating-point values are clamped. The initial specular reflectance for both front- and
back-facing materials is (0, 0, 0, 1).
GL_EMISSION
params contains four integer or floating-point values that specify the RGBA emitted
light intensity of the material. Integer values are mapped linearly such that the most
positive representable value maps to 1.0, and the most negative representable value
maps to - 1.0. Floating-point values are mapped directly. Neither integer nor
floating-point values are clamped. The initial emission intensity for both front- and
back-facing materials is (0, 0, 0, 1).
GL_SHININESS
params is a single integer or floating-point value that specifies the RGBA specular
exponent of the material. Integer and floating-point values are mapped directly. Only
values in the range [0, 128] are accepted. The initial specular exponent for both front-
and back-facing materials is 0.
GL_AMBIENT_AND_DIFFUSE
Equivalent to calling glMaterial twice with the same parameter values, once with
GL_AMBIENT and once with GL_DIFFUSE.
GL_COLOR_INDEXES
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Chapter 11