README

This module brings theme functions and a field formatter to display responsive images. It supports two different HTML tags:

• <IMG> tag using srcsrc attribute;
• <PICTURE> tag using <SOURCE> elements.

The <IMG> tag supports the sizes attribute allowing to set a relative viewport sizes for images at the field display configuration level, allowing the browser to proceed with better image selection for download.

This modules won't allow you to provide your own image styles, it only provides two different modes:

• Image keeps the original image ratio;
• Square image.

Future plans is to support more complex image styles (maybe by merging this module own styles using a user provided one).

This ships the Picturefill 2.0 polyfill to ensure graceful downgrade for old browsers.

Installation

Just download and enable the module.

Confguration

You may want to override available sizes for images, default is:

[285, 570, 855, 1140, 1440]

In order to override it, just add in your settings.php file:

$conf['iresponsive_image_size_list'] = [200, 300, 500, 1400, ...];

Usage

For image fields

Select Responsive image as display formatter, quite straightforward ?

Displaying manually an image

Use one of ireponsive_img or iresponsive_picture theme hooks and proceed this way with render arrays:

// Considering that $file is loaded file_managed.
$build['my_image'] = [
  '#theme'        => 'iresponsive_picture',
  '#image_uri'    => $file->uri,
  '#image_width'  => $file->width,
  '#image_height' => $file->height,
  '#image_alt'    => t("Some alternative text"),
  '#image_title'  => t("Some HTML title tag"),
  // Note that 'w' is the default, and keeps ratio while 's' is for square.
  '#modifier'     => 'w',
  // Default size must exist in iresponsive_image_size_list() function defaults
  // the 'iresponsive_image_size_list' variable if you overrided it.
  '#default_size' => $settings['default_size'],
  // If you set to true, this will include the original image, but without
  // any transformation (no square, etc...) in the image sources.
  '#include_full' => false,
  // Targetted image size in viewport percent (aka 'vh' unit in CSS).
  '#viewport'     => 50,
];

Or if you write Drupal 6 old school code (but you should never do this):

// Considering that $file is loaded file_managed.
theme(''iresponsive_picture', [
  'image_uri'    => $file->uri,
  'image_width'  => $file->width,
  'image_height' => $file->height,
  'image_alt'    => t("Some alternative text"),
  'image_title'  => t("Some HTML title tag"),
  // Note that 'w' is the default, and keeps ratio while 's' is for square.
  'modifier'     => 'w',
  // Default size must exist in iresponsive_image_size_list() function defaults
  // the 'iresponsive_image_size_list' variable if you overrided it.
  'default_size' => $settings['default_size'],
  // If you set to true, this will include the original image, but without
  // any transformation (no square, etc...) in the image sources.
  'include_full' => false,
  // Targetted image size in viewport percent (aka 'vh' unit in CSS).
  'viewport'     => 50,
]);