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#### Color Identifiers

Color identifiers may be declared to make scene files more readable and to parameterize scenes so that changing a single declaration changes many values. An identifier is declared as follows.

COLOR_DECLARATION:

`
  #declare
`IDENTIFIER `=` COLOR`;` | `
  #local
`IDENTIFIER `=` COLOR`;`

Where IDENTIFIER is the name of the identifier up to 40 characters long and COLOR is any valid specification. Note that there should be a semi-colon at the end of the declaration. This semi-colon is new with POV-Ray version 3.1. If omitted, it generates a warning and some macros may not work properly. See "#declare vs. #local" for information on identifier scope. Here are some examples....

     #declare White = rgb <1,1,1>;

     #declare Cyan = color blue 1.0 green 1.0;

     #declare Weird = rgb <Foo*2,Bar-1,Bob/3>;

     #declare LightGray = White*0.8;

     #declare LightCyan = Cyan red 0.6;

As the `LightGray` example shows you do not need any color keywords when creating color expressions based on previously declared colors. The last example shows you may use a color identifier with the keyword style syntax. Make sure that the identifier comes first before any other component keywords.

Like floats and vectors, you may re-define colors throughout a scene but the need to do so is rare.

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