Ticket #29211: background-image-cropper.php

<?php
/**
 * Plugin Name: Background Image Cropper
 * Plugin URI: https://core.trac.wordpress.org/ticket/32403
 * Description: Adds cropping to backgroud images in the Customizer, like header images have.
 * Version: 0.9
 * Author: Nick Halsey
 * Author URI: http://nick.halsey.co/
 * Tags: custom background, background image, cropping, customizer
 * License: GPL

=====================================================================================
Copyright (C) 2015 Nick Halsey

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with WordPress; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
=====================================================================================
*/

add_action( 'customize_register', 'background_image_cropper_register', 11 ); // after core
/**
 * Replace the core background image control with one that supports cropping.
 *
 * @todo ensure that the background-image context is properly set for any cropped background images.
 *
 * @param WP_Customize_Manager $wp_customize Customizer manager object.
 * @since 4.2.0
 */
function background_image_cropper_register( $wp_customize ) {
        $wp_customize->remove_control( 'background_image' );
        $wp_customize->add_control( new WP_Customize_Cropped_Image_Control( $wp_customize, 'background_image', array(
                'section'     => 'background_image',
                'priority'    => 0,
                'flex_width'  => true,
                'flex_height' => true,
                'width'       => 1920,
                'height'      => 1080,
        ) ) );
}