glMaterial assigns values to material parameters. There are two matched sets of material parameters. One, the set, is used to shade points, lines, bitmaps, and all polygons (when two-sided lighting is disabled), or just front-facing polygons (when two-sided lighting is enabled). The other set,, is used to shade back-facing polygons only when two-sided lighting is enabled. Refer to the glLightModel reference page for details concerning one- and two-sided lighting calculations. 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:
The material parameters can be updated at any time. In particular, glMaterial can be called between a call to glBegin and the corresponding call to glEnd. If only a single material parameter is to be changed per vertex, however, glColorMaterial is preferred over glMaterial (see glColorMaterial ). While the ambient, diffuse, specular and emission material parameters all have alpha components, only the diffuse alpha component is used in the lighting computation.
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glMaterial: man2/glMaterial.xml
glMaterial assigns values to material parameters. There are two matched sets of material parameters. One, the set, is used to shade points, lines, bitmaps, and all polygons (when two-sided lighting is disabled), or just front-facing polygons (when two-sided lighting is enabled). The other set,, is used to shade back-facing polygons only when two-sided lighting is enabled. Refer to the glLightModel reference page for details concerning one- and two-sided lighting calculations. 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:
The material parameters can be updated at any time. In particular, glMaterial can be called between a call to glBegin and the corresponding call to glEnd. If only a single material parameter is to be changed per vertex, however, glColorMaterial is preferred over glMaterial (see glColorMaterial ). While the ambient, diffuse, specular and emission material parameters all have alpha components, only the diffuse alpha component is used in the lighting computation.