Question

For a home project I need to plot (x,y) coordinates onto a 400×400 black and white-bitmap.

What perl module would you recoment and what image format (GIF?, PNG? other?) would be easiest to handle on OS X, Windows, Linux?

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EDIT My solution, based on GD, as recomended by Brian Agnew

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use strict;
use warnings;
use GD;
my $BitMap = GD::Image->new(400,400);

my $white = $BitMap->colorAllocate(255,255,255);
my $black = $BitMap->colorAllocate(0,0,0);       

# Frame the BitMap
$BitMap->rectangle(0,0,399,399,$black);
# Transparent image, white background color
$BitMap->transparent($white);

# plot some, just to show it works #
for my $x (0..100) {
   for my $y (0 .. 100) {
      $BitMap->setPixel(250+100*sin($x)-$y,150+125*cos($x)+$y,$black); 
   }
}

# write png-format to file
open my $fh,">","test.png" or die "$!";
binmode $fh;
print $fh $BitMap->png;
close($fh);

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Answer 1

Have a look at the GD module (which interfaces to the GD library). It makes creating graphics pretty trivial and has a wide range of output formats, including PNG and GIF.