The colour support is built around the idea of a system of
Colour Models. The Colour models supported by a driver vary,
but typically include
- <#900#>rgb<#900#>
- Red Green Blue: A comma separated list of three numbers
between~0 and~1, giving the components of the colour.
- <#901#>cmyk<#901#>
- Cyan Magenta Yellow [K]Black: A comma separated list of
four numbers between~0 and~1, giving the components of the colour
according to the additive model used in most printers.
- <#902#>gray<#902#>
- Grey scale: a single number between~0 and~1.
- <#903#>named<#903#>
- Colours accessed by name, e.g. `JungleGreen'. Not all
drivers support this model. The names must either be `known' to the
driver or added using commands described in |color.dtx|. Some drivers
support an extended form of the named model in which an `intensity' of
the colour may also be specified, so `JungleGreen, 0.5' would
denote that colour at half strength.
Note that the named model is really just given as an example
of a colour model that takes names rather than a numeric specication.
Other options may be provided locally that provide different colour
models, eg pantone (An industry standard set of colours),
x11 (Colour names from the UNIX window system), etc. The
standard distribution does not currently have such models, but the
named model could be used as an example of how to define a new
colour model. The names used in the named model are those
suggested by Jim Hafner in his colordvi and foiltex
packages, and implemented originally in the |color.pro| header file for
the dvips driver.