Background image and shadow

The code below is the source for this graph.

<?php
// Background image and shadow
require_once 'SVGGraph/autoloader.php';

$settings = [
  'auto_fit' => true,
  'back_colour' => '#eee',
  'back_stroke_width' => 0,
  'stroke_colour' => '#000',
  'axis_colour' => '#333',
  'axis_overlap' => 2,
  'axis_font' => 'Arial',
  'axis_font_size' => 10,
  'link_base' => '/',
  'link_target' => '_top',
  'minimum_grid_spacing' => 20,
  'show_subdivisions' => true,
  'show_grid_subdivisions' => true,
  'pad_right' => 20,
  'pad_left' => 20,
  'back_image' => getenv('base') . '/images/svgbg.png',
  'show_shadow' => true,
  'shadow_blur' => 4,
  'shadow_opacity' => 0.8,
  'shadow_offset_x' => 6,
  'bar_width' => 30,
  'axis_font_size' => 14,
  'back_image_mode' => 'tile',
  'back_image_width' => 320,
  'back_image_height' => 200,
  'show_subdivisions' => false,
  'grid_colour' => '#ccc',
  'grid_subdivision_colour' => '#ddd',
];

$width = 600;
$height = 200;
$values = [
  'Dough' => 30, 'Ray' => 50, 'Me' => 40, 'So' => 25, 'Far' => 45, 'Lard' => 35
];

$colours = [ [ 'red','yellow'], ['blue','white'] ];

$graph = new Goat1000\SVGGraph\SVGGraph($width, $height, $settings);
$graph->colours($colours);

$links = [
  'Dough' => 'jpegsaver.php',
  'Ray' => 'crcdropper.php',
  'Me' => 'svggraph.php'
];
$graph->values($values);
$graph->links($links);

$graph->render('BarGraph');

Please note: the source code above comes from a script used to generate one of the example graphs on the site. This is simply a wrapper page to apply highlighting and make the source code easier to read, so there is no content here to describe what the source code is doing.