glLightModelf

glLightModel: man2/glLightModel.xml

glLightModel sets the lighting model parameter. pname names a parameter and params gives the new value. There are three lighting model parameters: In RGBA mode, the lighted color of a vertex is the sum of the material emission intensity, the product of the material ambient reflectance and the lighting model full-scene ambient intensity, and the contribution of each enabled light source. Each light source contributes the sum of three terms: ambient, diffuse, and specular. The ambient light source contribution is the product of the material ambient reflectance and the light's ambient intensity. The diffuse light source contribution is the product of the material diffuse reflectance, the light's diffuse intensity, and the dot product of the vertex's normal with the normalized vector from the vertex to the light source. The specular light source contribution is the product of the material specular reflectance, the light's specular intensity, and the dot product of the normalized vertex-to-eye and vertex-to-light vectors, raised to the power of the shininess of the material. All three light source contributions are attenuated equally based on the distance from the vertex to the light source and on light source direction, spread exponent, and spread cutoff angle. All dot products are replaced with 0 if they evaluate to a negative value. The alpha component of the resulting lighted color is set to the alpha value of the material diffuse reflectance. In color index mode, the value of the lighted index of a vertex ranges from the ambient to the specular values passed to glMaterial using GL_COLOR_INDEXES. Diffuse and specular coefficients, computed with a (.30, .59, .11) weighting of the lights' colors, the shininess of the material, and the same reflection and attenuation equations as in the RGBA case, determine how much above ambient the resulting index is.

GL_LIGHT_MODEL_COLOR_CONTROL is available only if the GL version is 1.2 or greater.

@OpenGL_Version(OGLIntroducedIn.V1P0)
fn_glLightModelf glLightModelf;

See Also

glLight, glMaterial

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