#!/usr/bin/perl -w
use strict;
#use warnings;
use utf8;
use XSLoader;
use Carp;
use Imager;
use List::Util qw/ max /;
use Imager;
use Imager::Heatmap;
my $hmap = Imager::Heatmap->new(
    xsize  => 640,        # Image width
    ysize  => 480,        # Image height
    xsigma => 10,         # Sigma value of X-direction
    ysigma => 10,         # Sigma value of Y-direction
);
 
my @piont_datas = ( [ 10, 20, 50 ], [ 20, 40, 70 ] );
# Add point datas to construct density matrix
$hmap->insert_datas(@piont_datas); # @point_datas should be: ( [ x1, y1, weight1 ], [ x2, y2, weight2 ] ... )
 
#$hmap->insert_datas(...); # You can call multiple times to add large data that cannot process at a time.
 
# After adding datas, you could get heatmap as Imager instance.
my $img = $hmap->draw;
 
# Returned image is 4-channels image. So you can overlay it on other images.
my $base_img->rubthrough( src => $hmap->$img );  # Overlay on other images(see Imager::Transformations)

$img = Imager->new(
        xsize    => $hmap->xsize,
        ysize    => $hmap->ysize,
        channels => 4,
    );
# And you can access probability density matrix using matrix method if you like.
# In case, maybe you would like to create some graduations which be assigned to color of heatmap and its value.
$hmap->matrix;