README

Easy <picture> element generation for Silverstripe images.

Installation

composer require kinglozzer/silverstripe-picture

Usage

Configuration is performed via YAML:

Kinglozzer\SilverstripePicture\Picture:
  styles:
    Carousel:
      default:
        - {method: 'Fill', arguments: [375, 250]}
        - {method: 'Fill', arguments: [750, 500], descriptor: 750w}
      sources:
        "(min-width: 1024px)":
          - {method: 'Fill', arguments: [1024, 450]}
          - {method: 'Fill', arguments: [2048, 900], descriptor: 2x}

Each style can then be called from templates:

<div class="carousel__slide">
    {$Image.Carousel}
</div>

The generated HTML will look like this:

<picture>
    <source media="(min-width: 1024px)" srcset="/assets/image__FillWzEwMjQsNDUwXQ.jpg, /assets/image__FillWzIwNDgsOTAwXQ.jpg 2x" type="image/jpeg" />
    <img width="375" height="250" alt="image" src="/assets/image__FillWzM3NSwyNTBd.jpg" loading="lazy" srcset="/assets/image__FillWzM3NSwyNTBd.jpg, /assets/image__FillWzc1MCw1MDBd.jpg 750w" />
</picture>

Full example

Each source (and the “default” image) consists of one or more srcset image candidates, and each candidate consists of one or more manipulations and an optional descriptor (e.g. 2x, 300w).

Kinglozzer\SilverstripePicture\Picture:
  styles:
    Carousel:
      # The default <img /> that’s rendered if none of the <source> medias are matched
      default:
        # A list of image candidates to be output in the srcset attribute on the <img /> tag
        - {method: 'Fill', arguments: [200, 150]} # The first candidate will also be used as the <img /> "src"
        - {method: 'Fill', arguments: [400, 300], descriptor: 400w}
      # A list representing the <source> tags
      sources:
        "(min-width: 1128px)": # The "media" attribute for the source
          # A list of srcset image candidates
          - {method: 'Fill', arguments: [1024, 450]}
          - {method: 'Fill', arguments: [2048, 900], descriptor: 2x}
        "(min-width: 768px)":
          # If required, each srcset candidate can perform multiple manipulations
          -
            manipulations:
              - {method: 'ScaleWidth', arguments: [50]}
              - {method: 'Pad', arguments: [50, 100, 'FFFFFF']}
          -
            manipulations:
              - {method: 'ScaleWidth', arguments: [100]}
              - {method: 'Pad', arguments: [100, 200, 'FFFFFF']}
            descriptor: 2x