use strict;

use constant HUE_RANGE => 255;

my @HUES = (
	0, 		25, 	50, 	75, 	120, 	168, 	195, 	240, 	268, 	315);
#	0.0		0.1		0.2		0.3		0.4		0.5		0.6		0.7		0.8		0.9		1.0

&adjust_hue(0.3);

my @hues = (0 .. 4);
$_ *= 0.1 for @hues;

for (@hues) {
	&adjust_hue($_);
}

sub adjust_hue {
	my ($scale) = @_;

	my @hues = @HUES;
	push @hues, HUE_RANGE unless $hues[-1] == HUE_RANGE;
#	warn 'hues ', Dumper \@hues;
#	warn "n hues ", (scalar @hues), "\n";
	my $n_unique_hues = -1 + scalar @hues;
	my $scaled_index = $scale*$n_unique_hues;
	my $index = int $scaled_index;
	my $adjusted_hue = $hues[$index] + ($scaled_index - $index)*($hues[$index + 1] - $hues[$index]);
#	$adjusted_hue = eval $adjusted_hue; # This shouldn't be necessary. Somehow this sub was producing strings instead of numbers. Later, this strings would fail comparisons.
	if ($adjusted_hue == 75) {
		warn "  adjusted_hue ($adjusted_hue) equals 75\n";
	} else {
		warn "  adjusted_hue ($adjusted_hue) does not equal 75\n";
	}
	warn "scale $scale, scaled_index $scaled_index, index $index, adjusted_hue $adjusted_hue\n\n";
	$adjusted_hue;
}

##</code><code>##

  adjusted_hue (75) equals 75
scale 0.3, scaled_index 3, index 3, adjusted_hue 75

  adjusted_hue (0) does not equal 75
scale 0, scaled_index 0, index 0, adjusted_hue 0

  adjusted_hue (25) does not equal 75
scale 0.1, scaled_index 1, index 1, adjusted_hue 25

  adjusted_hue (50) does not equal 75
scale 0.2, scaled_index 2, index 2, adjusted_hue 50

  adjusted_hue (75) does not equal 75
scale 0.3, scaled_index 3, index 3, adjusted_hue 75

  adjusted_hue (120) does not equal 75
scale 0.4, scaled_index 4, index 4, adjusted_hue 120