"
for {set j 0} {$j < 9} {incr j} {
set r [expr int(255 * ($i + $j) / 16)]
set g [expr int(255 * (8 + $j - $i) / 16)]
set b [expr int(255 * (abs (4 - $i) + abs(4 - $j)) / 8)]
# determining the background luminosity (YIQ space of NTSC) and choosing
# the foreground color accordingly in order maintain maximum contrast
if { [expr ($r*0.29894)+($g*0.58704)+($b*0.11402)] > 148.0} {
set cssclass "dark"
} else {
set cssclass "bright"
}
set cell [format "%3d %3d %3d" $r $g $b]
puts [format \
"| %s | " \
$r $g $b $cssclass $cell]
}
puts ""
}
?>