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After we have defined the location and size of the sphere, we need to
describe the appearance of the surface. The texture statement
specifies these parameters. Texture blocks describe the color, bumpiness and
finish properties of an object. In this example we will specify the color
only. This is the minimum we must do. All other texture options except color
will use default values.
The color we define is the way we want an object to look if fully
illuminated. If we were painting a picture of a sphere we would use dark
shades of a color to indicate the shadowed side and bright shades on the
illuminated side. However ray-tracing takes care of that for you. We only
need to pick the basic color inherent in the object and POV-Ray brightens or
darkens it depending on the lighting in the scene. Because we are defining
the basic color the object actually has rather than how it
looks the parameter is called pigment.
Many types of color patterns are available for use in a pigment statement.
The keyword color specifies that the whole object is to be one
solid color rather than some pattern of colors. We can use one of the color
identifiers previously defined in the standard include file
colors.inc.
If no standard color is available for our needs, we may define our own color
by using the color keyword followed by red, green,
and blue keywords specifying the amount of red, green and blue
to be mixed. For example a nice shade of pink can be specified by:
color red 1.0 green 0.8 blue 0.8
Note: the international - rather than American - form "colour" is also acceptable and may be used anywhere that "color" may be used.
The values after each keyword should be in the range from 0.0 to 1.0. Any of the three components not specified will default to 0. A shortcut notation may also be used. The following produces the same shade of pink:
color rgb <1.0, 0.8, 0.8>
In many cases the color keyword is superfluous, so the shortest way to
specify the pink color is:
rgb <1.0, 0.8, 0.8>
Colors are explained in more detail in section "Specifying Colors".
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