colornam.txi

@code{(require 'color-names)}
@ftindex color-names

@noindent
Rather than ballast the color dictionaries with numbered grays,
@code{file->color-dictionary} discards them.  They are provided
through the @code{grey} procedure:


@defun grey k

Returns @code{(inexact->exact (round (* k 2.55)))}, the X11 color
grey@i{<k>}.
@end defun

@noindent
A color dictionary is a database table relating @dfn{canonical}
@cindex canonical
color-names to color-strings
(@pxref{Color Data-Type, External Representation}).

@noindent
The column names in a color dictionary are unimportant; the first
field is the key, and the second is the color-string.


@defun color-name:canonicalize name
Returns a downcased copy of the string or symbol @var{name} with
@samp{_}, @samp{-}, and whitespace removed.
@end defun


@defun color-name->color name table1 table2 @dots{}


@var{table1}, @var{table2}, @dots{} must be color-dictionary tables.  @code{color-name->color} searches for the
canonical form of @var{name} in @var{table1}, @var{table2}, @dots{} in order; returning the
color-string of the first matching record; #f otherwise.
@end defun


@defun color-dictionaries->lookup table1 table2 @dots{}


@var{table1}, @var{table2}, @dots{} must be color-dictionary tables.  @code{color-dictionaries->lookup} returns a
procedure which searches for the canonical form of its string argument
in @var{table1}, @var{table2}, @dots{}; returning the color-string of the first matching
record; and #f otherwise.
@end defun


@defun color-dictionary name rdb base-table-type


@var{rdb} must be a string naming a relational database file; and the symbol
@var{name} a table therein.  The database will be opened as
@var{base-table-type}.  @code{color-dictionary} returns the read-only table @var{name} in database
@var{name} if it exists; #f otherwise.


@end defun
@defun color-dictionary name rdb

@var{rdb} must be an open relational database or a string naming a relational
database file; and the symbol @var{name} a table therein.  @code{color-dictionary} returns the
read-only table @var{name} in database @var{name} if it exists; #f otherwise.
@end defun


@defun load-color-dictionary name rdb base-table-type


@defunx load-color-dictionary name rdb

@var{rdb} must be a string naming a relational database file; and the symbol
@var{name} a table therein.  If the symbol @var{base-table-type} is provided, the database will
be opened as @var{base-table-type}.  @code{load-color-dictionary} creates a top-level definition of the symbol @var{name}
to a lookup procedure for the color dictionary @var{name} in @var{rdb}.

The value returned by @code{load-color-dictionary} is unspecified.
@end defun