2012

3 Browse to and select your image file, and click Open.
4 You may then need to adjust some of the texture parameters of the new
material, for example its scale, rotation, offset or reflection (if it’s back
to front). These may all be edited in the Texture tab. See
Edit Presenter
Materials
(page 557) for more information.
Advanced Materials
Internally, a material is defined by four shaders from different classes: Color,
Transparency, Reflectance and Displacement. Each class of shader
controls a different aspect of a material's behavior. There are many types of
shader in each class, each type being defined by its own set of parameters.
■ A Color shader is used to define the color of a surface at any point in
space. It may be as simple as a plain color which specifies all parts of the
surface to have a uniform color, or it may define complex surface patterns
such as marble or wood. Every material must have a color shader.
■ The behavior of a surface in the presence light is represented by a
reflectance shader which defines how much light is reflected by the
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