The color of the objects we see in the natural
world is a result of the way objects interact with light. When a
light wave strikes an object, it can be absorbed, reflected, or
refracted by the object. All objects have a degree of reflection
and absorption.
NoteIn the natural world,
light can also be transmitted by an object. That is, light can pass
through an object with no effect (an x-ray, for example). These types
of light, however, are not represented in Autodesk® Maya® because they have no
visual effect.
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Absorption. Light stops at the object
and does not reflect or refract. Objects appear dark or opaque.
Example: wood.
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Reflection on a smooth
surface.
Light bounces off the
surface of a material at an angle equal to the angle of the incoming
light wave.
Example: mirrors or glass. See also
Diffuse, Specular, and Glossy reflection.
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Reflection on a rough
surface (also called Scatter).
Light waves bounce off
at many of angles because the surface is uneven.
Example: the earth (that’s
why the sky is blue).
See also
Diffuse, Specular, and Glossy reflection.
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Refraction Light goes through the
object and bends at an angle.
Example: diamond (greater angle) or water (lesser
angle)
See also
Diffuse, Specular, and Glossy refraction of light.
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Diffuse, Specular, and
Glossy reflection
Reflection
is divided into three types: diffuse, specular, and glossy.
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Diffuse reflection. Diffuse surfaces reflect
(scatter) light in many angles.
Diffuse reflection accounts
for more of the color than any other type of distribution because
most objects are opaque and reflect light diffusely.
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Glossy reflection. Glossy surfaces are actually
specular surfaces with micro surfaces at angles to surface plane.
These micro surfaces
reflect light not only specularly but also diffusely (at angles
very close to the specular transmission), giving the surface a glossy
appearance.
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Specular reflection. Specular surfaces reflect
light at the same as the angle at which the light strikes the surface.
Specular
reflection gives objects a glossy or mirror-like appearance.
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Diffuse, Specular, and
Glossy refraction of light
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Diffuse refraction. Diffuse refraction scatters
light in many angles.
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Glossy refraction. Glossy surfaces are actually
specular surfaces with micro surfaces at angles to surface plane.
These micro surfaces
refract light not only specularly but also diffusely (at angles
very close to the specular transmission), giving the surface a glossy
appearance.
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Specular refraction. Specular surfaces reflect
light at the same as the angle at which the light strikes the surface.
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