| puts "<html><head>" |
| puts "<style>\n td { font-size: 12px; text-align: center; padding-left: 3px; padding-right: 3px}" |
| puts " td.bright { color: #eee; }\n td.dark { color: #222; }\n</style>" |
| puts "</head><body>" |
| puts "<table>" |
| |
| # we create a 9x9 table selecting a different background for each cell |
| |
| for {set i 0} { $i < 9 } {incr i} { |
| puts "<tr>" |
| for {set j 0} {$j < 9} {incr j} { |
| |
| set r [expr int(255 * ($i + $j) / 16)] |
| set g [expr int(255 * (8 - $i + $j) / 16)] |
| set b [expr int(255 * ($i + 8 - $j) / 16)] |
| |
| # determining the background luminosity (YIQ space of NTSC) and choosing |
| # the foreground color accordingly in order maintain maximum contrast |
| |
| if { [expr ($r*0.29894)+($g*0.58704)+($b*0.11402)] > 128.0} { |
| set cssclass "dark" |
| } else { |
| set cssclass "bright" |
| } |
| |
| puts [format "<td bgcolor=\"%02x%02x%02x\" class=\"%s\">$r $g $b</td>" $r $g $b $cssclass] |
| } |
| puts "</tr>" |
| } |
| puts "</table>" |
| puts "</body></html>" |
