aparler/RosettaCodeData
1
0
Fork 0
Code Issues 12 Pull requests 3 Projects Releases Packages Wiki Activity Actions

langs a-z

Browse source
This commit is contained in:
Ingy döt Net 2013-04-10 22:43:41 -07:00
parent db842d013d
commit d066446780
11389 changed files with 98361 additions and 1020 deletions
Download patch file Download diff file Expand all files Collapse all files

30
Task/Bitmap-Bresenhams-line-algorithm/Perl-6/bitmap-bresenhams-line-algorithm.pl6 Normal file
View file

@ -0,0 +1,30 @@
sub line(Bitmap $bitmap, $x0 is copy, $x1 is copy, $y0 is copy, $y1 is copy) {
my $steep = abs($y1 - $y0) > abs($x1 - $x0);
if $steep {
($x0, $y0) = ($y0, $x0);
($x1, $y1) = ($y1, $x1);
}
if $x0 > $x1 {
($x0, $x1) = ($x1, $x0);
($y0, $y1) = ($y1, $y0);
}
my $Δx = $x1 - $x0;
my $Δy = abs($y1 - $y0);
my $error = 0;
my $Δerror = $Δy / $Δx;
my $y-step = $y0 < $y1 ?? 1 !! -1;
my $y = $y0;
for $x0 .. $x1 -> $x {
my $pix = Pixel.new(R => 100, G => 200, B => 0);
if $steep {
$bitmap.set-pixel($y, $x, $pix);
} else {
$bitmap.set-pixel($x, $y, $pix);
}
$error += $Δerror;
if $error >= 0.5 {
$y += $y-step;
$error -= 1.0;
}
}
}