Suppose you have a color, perhaps the result of a tk_chooseColor operation, or some sort of "$widget configure -fg" introspection and transformation. Is there a way to say that color in English?
Sure. Just use the code below:
proc get_color_name {color_value permitted_list} {
if {![regexp #(.*) $color_value -> rgb]} {
return $color_value
}
scan $rgb %2x%2x%2x r0 g0 b0
set least_distance 10000
set set_name unknown
foreach name $permitted_list {
set list {}
foreach part [winfo rgb . $name] {
scan [format %4x $part] %2x%2x first second
lappend list $first
}
foreach {r g b} $list {}
set d [expr abs($r - $r0) + abs($g - $g0) + abs($b - $b0)]
if {!$d} {
return $name
}
if {$d < $least_distance} {
# puts "$name, at ($r, $g, $b), is within $d of ($r0, $g, $b0)."
set least_distance $d
set best_name $name
}
}
return "$best_name +/ $least_distance"
}