glColorMaterialface

glColorMaterial is an OpenGL function used with the fixed-function lighting pipeline to connect the current color to material properties. When GL_COLOR_MATERIAL is enabled, changes to the current color can automatically update specified material properties for selected faces, simplifying how objects are colored under lighting. This feature is part of compatibility profiles and is not available in modern core profiles without shader-based workarounds.

The function takes two parameters: face and mode. The face argument selects which polygon face the material updates apply to. Valid values include GL_FRONT, GL_BACK, and GL_FRONT_AND_BACK, with the latter applying to both faces. The mode argument specifies which material properties will track the color. Common options are GL_AMBIENT, GL_DIFFUSE, GL_SPECULAR, GL_EMISSION, and GL_AMBIENT_AND_DIFFUSE, indicating that the current color should update the corresponding material property (or properties) for the chosen face(s).

Usage pattern typically involves enabling color-material tracking and then issuing color commands. For example, glColorMaterial(GL_FRONT, GL_DIFFUSE) followed by glEnable(GL_COLOR_MATERIAL) makes subsequent glColor calls adjust the front-face diffuse material. If GL_COLOR_MATERIAL is disabled, glColor calls affect only the color attribute and do not influence the lighting material state.

Because glColorMaterial belongs to the fixed-function pipeline, it is deprecated in modern OpenGL. In contemporary contexts, material properties are usually supplied via shader uniforms, vertex attributes, or textures. Nonetheless, glColorMaterial remains a concise way to tie color to lighting in legacy applications and demos that rely on the fixed-function pipeline.