Colour set and range functions

The code below is the source for this graph.

<?php
// Colour set and range functions
require_once 'SVGGraph/autoloader.php';

$settings = [
  'auto_fit' => true,
  'back_stroke_width' => 2,
  'show_axis_text_h' => false,
  'grid_division_v' => 1,
  'show_tooltips' => false,
  'bar_space' => 5,
  'stroke_width' => 0,
  'back_colour' => ['#ddd', 'pattern' => 'polkadot3', 'size' => 20],
  'show_grid' => true,
  'grid_colour' => '#666',
];

$columns = 24;
$values = [];

for($i = 0; $i < $columns; ++$i) {
  $values[0][$i] = 1;
  $values[1][$i] = 1;
  $values[2][$i] = 1;
  $values[3][$i] = 1;
  $values[4][$i] = 0.75 + 0.25 * cos($i * 2 * M_PI / $columns);
}

$graph = new Goat1000\SVGGraph\SVGGraph(670, 200, $settings);

$colours = [
  'red',
  '#0f0',
  ['red','blue'],
  ['green', 'white', 'h'],
  ['blue', 'white:0.1', 'blue'],
  ['red', 'pattern' => 'polkadot'],
  ['green', 'pattern' => 'line', 'angle' => 45],
  'blue',
];
$graph->colourSet(0, $colours);
$graph->colourRangeHexRGB(1, '#f00', '#00f');
$graph->colourRangeHexHSL(2, '#f00', '#00f');
$graph->colourRangeHexHSL(3, '#f00', '#00f', 1);

$graph->values($values);
$graph->render('StackedBarGraph');

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.