Thread: Relation between material colors and light colors.

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    Relation between material colors and light colors.

    I have been wondering how to figure out how the colors I set for objects (ambient, diffuse, specular) are affected by the ambient, diffuse and specular colors of a lights source. I know what the attributes of lighting represent, but when it comes to the object's ambient, specular, and diffuse attributes I get lost.

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    Frequently Quite Prolix dwks's Avatar
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    You mean, you set some attributes on an object, and some attributes for a light source that is shining on that object, and you want to figure out the resulting attributes for that object with the attributes of the light source applied to it?

    Are you using DirectX, OpenGL, or something else?
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    Lean Mean Coding Machine KONI's Avatar
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    Imagine a shiny white surface onto which you point a red light source ... try to close your eyes and imagine the scene in your mind. And now, try the same thing with a black shiny surface. The result is quite different...since the value of the reflexion color is not only dependent on the light source but also the material of the object.

    If you're not convinced, try to download a 3D editor like 3DS Max and play around with the material editor, you'll immediately notice the difference.

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    Officially An Architect brewbuck's Avatar
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    Quote Originally Posted by indigo0086 View Post
    I have been wondering how to figure out how the colors I set for objects (ambient, diffuse, specular) are affected by the ambient, diffuse and specular colors of a lights source. I know what the attributes of lighting represent, but when it comes to the object's ambient, specular, and diffuse attributes I get lost.
    Not sure exactly what question you're asking. The ambient property determines how the object "self-lights," i.e. light contributions from the environment as a whole as opposed to a particular light source. Diffuse property describes how non-specular interactions color the object. Specular property describes specular interactions.

    The difference between specular and diffuse reflection has to do with how the color of the light source interacts with the color of the object. In the specular region, the reflected color is almost entirely determined by the light source. In the diffuse region it is determined by the color of the object.

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