@Section
   @Title { Colour }
@Begin
@PP
An arbitrary Lout object may be printed in colour, like this:
@ID {
@Code "red @Colour hello"
||7ct
@Fig {
red @Colour hello
}
}
@Code "@Colour" may also be spelt {@Code "@Color"}.  Of course, a colour
printing device is needed to see the effect.  The @Code "@Colour" symbol
is intended to provide a fixed palette of colours indicated by names,
including {@Code "white"}, {@Code "grey"}, {@Code "gray"}, {@Code "black"},
{@Code "red"}, {@Code "green"}, and {@Code "blue"} at least.
@PP
An unlimited range of colours can be obtained with the
{@Code "@RGBColour"} (or {@Code "@RGBColor"}) symbol, which is given
three numbers in the range 0 to 1 specifying the required intensity of
red, green and blue colour in that order.  For example,
@ID @Code "{1.0 0.0 0.0} @RGBColour hello"
is equivalent to {@Code "red @Colour hello"}.  There is also
{@Code "@HSBColour"} (or {@Code "@HSBColor"}) for specifying colour
using the hue-saturation-brightness model (see [{@Ref adobe90}],
Section 4.8).
@End @Section
