README

A library for easy introduction of Responsive Images to WordPress site.

Requirements

• PHP 8.0
• WordPress

Installation

Clone WP Responsive Images library or install with composer:

$ composer require vvv3/wp-responsive-images

How to use

The library contains classes and helpers for easy introduction of Responsive Images to a WordPress site.

ImgUtils::resizeImg()

The \WPRI\ImgUtils::resizeImg method returns a link to the modified image according to the passed parameters.

Usage:

 <img src="<?php echo ImgUtils::resizeImg( $url, $width, $height, $crop ); ?>" >

• $url - URL to image file to resize
• $width - width value, integer
• $height - height value, integer
• $crop - bool flag crop or not

Returns: string resized image url

Example:

use WPRI\ImgUtils;
...
<img src="<?php echo ImgUtils::resizeImg( get_the_post_thumbnail_url( get_the_ID(), 'full' ), 380, 250, true ); ?>" >

ImgUtils::imgForPost, ImgUtils::pictureForPost

Helpers ImgUtils::imgForPost and ImgUtils::pictureForPost return a Responsive <img> or <picture> tag by post Id. You may set list of media queries with image with for this query, double pixel ratio, aspect ratio for the images, loading="lazy" native attribute or any other additional attribute.

Usage:

ImgUtils::imgForPost(
    int $postId,
    array $mqWithWidth = [],
    bool $pixelRatio2x = false,
    int|float|null $aspectRatio = null,
    bool $lazy = false,
    array $attrs = [])

ImgUtils::pictureForPost(
    int $postId,
    array $mqWithWidth = [],
    bool $pixelRatio2x = false,
    int|float|null $aspectRatio = null,
    bool $lazy = false,
    array $attrs = [])

Returns:

string <img> or <picture> tag accordingly or empty string on error

Example:

echo ImgUtils::imgForPost(
		get_the_ID(),
		[   // format: ['media-query' => width-in-px(int), ... , default-width-in-px(int) ]
			'(min-width: 1200px)' => 730,
			'(min-width: 768px)'  => 690,
			545, // dafault width, if no media query aplied
		],
		false,
		16/9,
		true,
		['class' => 'my-class']
	);

echo ImgUtils::pictureForPost(
		get_the_ID(),
		[
			'(max-width: 767px)'  => 545,
			'(max-width: 1199px)' => 690,
			730
		] );

ImgUtils::imgByAttachmentId, ImgUtils::pictureByAttachmentId

Helpers ImgUtils::imgByAttachmentId and ImgUtils::pictureByAttachmentId return a Responsive <img> , <picture> tag by attachment Id.

Also you can do any combination of parameters of Picture or Img responsive tags with WPRI\ResponsiveImages\ classes :

if ( has_post_thumbnail( $postId ) ) {
    try {
        $originUrl = get_the_post_thumbnail_url( $postId, 'full' );
        $resizer   = Resizer::makeWithUrl( $originUrl );
        $picture =
            Picture::make(
                $originUrl, // original url for default img tag
                'customAlt', // alt for default img tag
                null, // width attribute, by default as at $originUrl image
                null, // height attribute, by default as at $originUrl image
                [     // sourses
                    Source::make(
                       [ // SrcsetItems
                        SrcsetItem::makeWithResize( $resizer->setWidth( 730 ), '1x' ),
                        SrcsetItem::makeWithResize( $resizer->setWidth( 730 * 2 ), '2x' ),
                    ],
                        [], // may add sizes
                        '(min-width: 1200px)', // may add media
                        'image/jpeg'  // may add image mime-type
                    ),

                    Source::make( [
                        SrcsetItem::makeWithResize( $resizer->setWidth( 690 ), '1x' ),
                        SrcsetItem::makeWithResize( $resizer->setWidth( 690 * 2 ), '2x' ),
                    ],
                        [],
                        '(min-width: 768px)'
                    ),

                    Source::make( [
                        SrcsetItem::makeWithResize( $resizer->setWidth( 545 ), '1x' ),
                        SrcsetItem::makeWithResize( $resizer->setWidth( 545 * 2 ), '2x' ),
                    ] ),
                ] )
                   ->setPictureAttr( 'class', 'custom-picture-class' )
                   ->setPictureAttr( 'data-some', 'custom-picture-attr' )
                   ->setImgAttr( 'class', 'custom-img-class' )
                   ->setImgAttr( 'data-some', 'custom-img-attr' )
                   ->render();
    } catch ( \Exception $ex ) {
        error_log( "\nFile: {$ex->getFile()}\nLine: {$ex->getLine()}\nMessage: {$ex->getMessage()}\n" );
        $picture = '';
    }
    echo $picture;
}