HP Workstation zx2000 OpenGL 1.1 Reference for HP-UX 11.x - Page 64

C glColorMaterial glColorMaterial glColorMaterial: cause a material color to track the current color. C Specification void glColorMaterial( GLenum face, GLenum mode) Parameters face mode Specifies whether front, back, or both front and back material parameters should track the current color. Accepted values are GL_FRONT, GL_BACK, and GL_FRONT_AND_BACK. The initial value is GL_FRONT_AND_BACK. Specifies which of several material parameters track the current color. Accepted values are GL_EMISSION, GL_AMBIENT, GL_DIFFUSE, GL_SPECULAR, and GL_AMBIENT_AND_DIFFUSE. The initial value is GL_AMBIENT_AND_DIFFUSE. Description glColorMaterial specifies which material parameters track the current color. When GL_COLOR_MATERIAL is enabled, the material parameter or parameters specified by mode, of the material or materials specified by face, track the current color at all times. To enable and disable GL_COLOR_MATERIAL, call glEnable and glDisable with argument GL_COLOR_MATERIAL. GL_COLOR_MATERIAL is initially disabled. Notes glColorMaterial makes it possible to change a subset of material parameters for each vertex using only the glColor command, without calling glMaterial. If only such a subset of parameters is to be specified for each vertex, calling glColorMaterial is preferable to calling glMaterial. Call glColorMaterial before enabling GL_COLOR_MATERIAL. Calling glDrawElements may leave the current color indeterminate. If glColorMaterial is enabled while the current color is indeterminate, the lighting material state specified by face and mode is also indeterminate. If the GL version is 1.1 or greater, and GL_COLOR_MATERIAL is enabled, evaluated color values affect the results of the lighting equation as if the current color were being modified, but no change is made to the tracking lighting parameter of the current color. Errors • GL_INVALID_ENUM is generated if face or mode is not an accepted value. 64 Chapter 3