SvelteKit

sveltekit-cover
Use TwicPics SvelteKit Components to get images and videos integration best practices out-of-the-box.

Discover our demonstrations and integration examples in our online demo project.

Installation

Add the @twicpics/components package to your project as a dev dependency:

# Using yarn
yarn add @twicpics/components -D

# Or using npm
npm install @twicpics/components --D

Setup

You will need a TwicPics domain to initialize the package. Create an account for free to get your domain.

Setting up TwicPics Components in your SvelteKit project

Add the import part:

  // import TwicPics sveltekit components
  import { installTwicpics } from "@twicpics/components/sveltekit";
  // import TwicPics components css
  import "@twicpics/components/style.css";

And the configuration part (see Setup Options):

  installTwicpics( {
    // domain is mandatory
    "domain": "https://<your-domain>.twic.pics"
  } );

into the main layout of your SvelteKit project.

If you don't already have a layout that applies to all the pages of your application, simply create it by adding +layout.svelte file, right next to your entry point src/routes/+page.svelte.

src/routes/+layout.svelte

<script>
  // Here is an example of +layout.svelte file
  import { installTwicPics } from "@twicpics/components/sveltekit";
  import "@twicpics/components/style.css";
  installTwicPics( {
      "domain": `https://<your-domain>.twic.pics`,
  } );
</script>
<slot />

Setup Options

OptionDescriptionTypeDefault
anticipationTwicPics will lazy-load images by default. To avoid too abrupt a transition with elements appearing into view and then images very obviously loading afterwards, TwicPics will "anticipate" lazy loading by a factor of the actual viewport. This behavior is controlled by this setting.Number0.2
breakpointsCustomizes breakpoints value for responsive behavior.object{ xs: 320, sm: 640, md: 768, lg: 1024, xl: 1280, '2xl': 1536 }
domainThis is your very own TwicPics domain. Providing it is mandatory.String
envCan be debug, offline or production. When set to debug, a gray lightweight svg placeholder that displays its intrinsic dimensions is displayed in place of all medias targeted by their src value. When set to offline, these medias are replaced by a simple placeholder that allows to visualise their display area.String"production"
handleShadowDomMust be set to true when using TwicComponents within a shadow DOM.booleanfalse
maxDPRTwicPics will take the "Device Pixel Ratio" (DPR) of the current device into consideration when determining the sizes of images to load. By default, it will not take a DPR greater than 2 into consideration. If the DPR of the device is higher than 2, TwicPics will assume it to be 2. Using maxDPR, you can lower this limit down to 1 or be more permissive (for instance by setting it to 3 or 4).Number2
pathPath to prepend to all src attributes. For instance, if path is "some/folder" then a src attribute set to "image.jpg" will be expanded into "some/folder/image.jpg"String
stepTo avoid requesting too may variants of the same image, TwicPics will round the width of images to the closest multiple of step. The height will then be computed in order to respect the original aspect ratio.Integer10

Usage

Import TwicPics Components such as TwicImg, TwicPicture, or TwicVideo into your template files.

Replace standard img, picture, or video tags with these components to enhance functionality and customization (see Components Properties).

Add the import part in the script section of your .svelte file:

<script>
  // this component will be used in instead of an img element.
  import { TwicImg } from "@twicpics/components/sveltekit";

  // this component will be used in instead of a `picture` element.
  import { TwicPicture } from "@twicpics/components/sveltekit";

  // this component will be used in instead of an video element.
  import { TwicVideo } from "@twicpics/components/sveltekit";
</script>

or

<script>
  // this component will be used in instead of an img element.
  import TwicImg from "@twicpics/components/sveltekit/TwicImg.svelte";

    // this component will be used in instead of a `picture` element.
  import TwicPicture from "@twicpics/components/sveltekit/TwicPicture.svelte";

  // this component will be used in instead of a video element.
  import TwicVideo from "@twicpics/components/sveltekit/TwicVideo.svelte";
</script>

then, use <TwicImg>, <TwicPicture> or <TwicVideo> instead of standard tags <img>, picture or <video> (see Components Properties).

Basic usage

<!-- component.svelte-->
<script>
  import TwicImg from "@twicpics/components/sveltekit/TwicImg.svelte";
</script>

<main>
  <TwicImg src="path/to/your/image"></TwicImg>
</main>

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Bulk loading with TwicView

By default, <TwicImg> and <TwicVideo> will only start loading when they enter the viewport. But sometimes, you may want to load multiple assets in bulk instead of lazy loading them. This is where <TwicView> comes into play.

The <TwicView> component eagerly loads all of his <TwicImg> and <TwicVideo> children as soon as it enters the viewport (depending on your anticipation settings.)

For example, if you're building a carousel, you might want to bulk-load all images. In the following code, all three images will be loaded when TwicView comes into the viewport:

<TwicView>
  <TwicImg src="image1.jpg" />
  <TwicImg src="image2.jpg" />
  <TwicImg src="image3.jpg" />
</TwicView>

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Critical Images

TwicPicture streamlines the use of picture elements and srcset attributes.

It operates independently of the TwicPics Script and dynamically generates source elements and srcset attributes from a single master file using variants transformed through the TwicPics API.

Resolution switching

The following examples illustrate how to serve different resolutions of the same image according to breakpoints and maxDPR defined in Setup Options.

<!-- Populate srcset and fallback with a list of squared variants -->
<TwicPicture src="your-lcp-image.jpg"></TwicPicture>
<!-- Populate srcset and fallback with a list of 16/9 variants -->
<TwicPicture
  src="your-lcp-image.jpg"
  ratio="16/9"
></TwicPicture>
<!-- eager disables lazy-loading and sets fetchpriority to high -->
<TwicPicture
  src="your-lcp-image.jpg"
  eager
></TwicPicture>
<!-- for best performances set sizes attribute is a best practice -->
<TwicPicture
  src="your-lcp-image.jpg"
  eager
  sizes="
    (min-width: 1000px) 33vw,
    96vw
  "
></TwicPicture>

For a comprehensive list of properties and detailed information, please refer to TwicPicture.

Art Direction

To achieve art direction, configure the following TwicPicture's properties following the mobile-first principle:

  • anchor
  • focus
  • mode
  • position
  • ratio

The following examples illustrate how to serve various image variations based on distinct artistic directions and default breakpoint values:

<!--
  This will display a :
  squared variant (default ratio) for screen with a width < 1024 px
  4/3 variant for screen with a width >= 1024 px
  21/9 variant for screen with a width >= 1280 px
-->
<TwicPicture
  src="art.jpg"
  alt="Art Direction Example"
  ratio="
    @lg 4/3
    @xl 21/9
  "
/>

<!--
  This allows to change the focus point for screen with a width >= 1280 px
-->
<TwicPicture
  src="art.jpg"
  alt="Art Direction Example"
  ratio="
    @lg 4/3
    @xl 21/9
  "
  focus="@xl top"
/>

<!--
  You can also configure a custom breakpoint
-->
<TwicPicture
  src="art.jpg"
  alt="Art Direction Example"
  ratio="
    @lg 4/3
    @xl 21/9
  "
  focus="
    @666 bottom
    @xl top
  "
/>

Default breakpoint values can be configured here.

Image magnifier

The <TwicImg> component lets you display a lazy loaded, zoomed version of your image on mouseover.

To activate the zoom feature, set the zoom property to a number strictly greater than 1. This number represents the magnification factor of your image.

For example:

  <TwicImg src="image1.jpg" zoom="2" />
  <TwicImg src="image2.jpg" zoom="2.5" />

The zoom factor can also be configured through the --twic-zoom CSS variable.

To activate the style-driven zoom, set the zoom property to 'css' and add a new rule to your stylesheet.

For example:

  <TwicImg src="image3.jpg" zoom="css" class=".zoom-3"/>
.zoom-3 {
  --twic-zoom:3;
}

It applies only to the TwicImg component in cover mode.

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Lifecycle

For TwicImg and TwicVideo components, binding state props gives access to the loading state of your image or video.

Here are the values the Component will emit :

  • new: when the img or video source has not started loading
  • loading: when the img or video source is loading
  • done: when the img or video source has successfully loaded
  • error: when an error occurred while loading the img or video source
<script>
  // component.svelte
  import TwicImg from "@twicpics/components/sveltekit/TwicImg.svelte";
  let state;

  $: {
    // Implement the logic here
    console.log( `TwicComponent emits a new state`, state );
  }
</script>


<TwicImg
  bind:state
  src="path/to/your/image"
/>

Another approach is to listen to the statechange event.

<script>
  // component.svelte
  import TwicImg from "@twicpics/components/sveltekit/TwicImg.svelte";
  let state;

  const handleStateChange = ( e ) => {
    // Implement the logic here
    state = e.detail;
    console.log( `TwicComponent emits a new state`, state );
  }
</script>


<TwicImg
  on:statechange={handleStateChange}
  src="path/to/your/image"
/>

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Refit example

<TwicImg> and <TwicPicture> components allow to reframe your image on the main subject(s) they contain.

In cover mode, the resulting image will respect the ratio while maximizing the area occupied by the main subject(s).

In contain mode, the image is cropped as close as possible to the main subject(s).

To activate automatic cropping, add the refit property to your component.

By default, the subject will be placed at the center of the resulting image, but it is possible to align the subject with a given border by specifying an anchor.

Also, by default, the subject will touch the borders of the resulting image. This can be avoided by setting refit with a comma-separated length value defining padding.

For example:

  <!-- default refit: centered object(s), no padding around -->
  <TwicImg src="image1.jpg" refit />

  <!-- main subject(s) will be left aligned -->
  <TwicImg src="image3.jpg" anchor="left" refit/>

  <!-- a 5% padding will be applied around main subject(s) -->
  <TwicImg src="image2.jpg" refit="5p" />

  <!-- a 5% padding will be applied vertically, a 10% padding will be applied horizontally -->
  <TwicImg src="image3.jpg" refit="5p,10p" />

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Style-Driven Approach

You can set up TwicImg and TwicVideo components using pure CSS and the power of CSS variables.

<script>
  // component.svelte
  import TwicImg from "@twicpics/components/sveltekit/TwicImg.svelte";
</script>

<style>
  .landscape {
    --twic-ratio: calc(4 / 3);
  }

  .portrait {
    --twic-ratio: calc(3 / 4);
  }

  .square {
    --twic-ratio: calc(1);
  }

  .lg {
    width: 300px;
  }

  .md {
    width: 150px;
  }

  .sm {
    width: 100px;
  }
</style>

<main>
  <div class="landscape">
    <TwicImg src="path/to/your/image"></TwicImg>
  </div>
  <div class="square">
    <TwicImg src="path/to/your/image"></TwicImg>
  </div>
  <div class="portrait">
    <TwicImg src="path/to/your/image"></TwicImg>
  </div>
  <div class="lg">
    <TwicImg src="path/to/your/image"></TwicImg>
  </div>
  <div class="md">
    <TwicImg src="path/to/your/image"></TwicImg>
  </div>
  <div class="sm">
    <TwicImg src="path/to/your/image"></TwicImg>
  </div>
</main>

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Responsive Example

Setting up TwicImg and TwicVideo components using CSS and CSS variables enables hassle-free responsive designs.

Your template features a single component that will follow your CSS directives and behave responsively.

<script>
  // component.svelte
  import TwicImg from "@twicpics/components/sveltekit/TwicImg.svelte";
</script>

<style>
  .style-driven-responsive {
    --twic-ratio: calc(2 / 3);
    --twic-mode: cover;
    margin: auto;
  }

  @media (min-width: 640px) {
    .style-driven-responsive {
      --twic-ratio: calc(1);
    }
  }

  @media (min-width: 768px) {
    .style-driven-responsive {
      --twic-ratio: calc(4 / 3);
    }
  }

  @media (min-width: 1024px) {
    .style-driven-responsive {
      --twic-ratio: calc(16 / 9);
    }
  }

  @media (min-width: 1280px) {
    .style-driven-responsive {
      --twic-ratio: calc(1.85);
    }
  }

  @media (min-width: 1536px) {
    .style-driven-responsive {
      --twic-ratio: calc(21 / 9);
    }
  }
</style>

<main>
  <div class="style-driven-responsive">
    <TwicImg src="path/to/your/image"></TwicImg>
  </div>
</main>

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Working with ratio="none"

With TwicPicture

It is helpful if you want to display an image with its intrinsic aspect ratio without cropping.

When using ratio="none", there is no CLS optimization, and you are responsible for it.

<!-- will display your image with it's intrinsic ratio, without any cropping -->
<TwicPicture>
  src="path/to/your/image"
  ratio="none"
</TwicPicture>

With TwicImg and TwicVideo

It is particularly useful when creating a "hero" banner. You can specify the height of your image while respecting its natural aspect ratio, and optimizing your Cumulative Layout Shift (CLS) metric.

When using ratio="none", you are responsible for properly sizing the component.

<script>
  // component.svelte
  import TwicImg from "@twicpics/components/sveltekit/TwicImg.svelte";
</script>

<style>
  /* You are responsible for properly sizing the component. */
  .hero-image {
    height:500px;
  }

  @media (min-width: 1024px) {
    .hero-image {
      height:300px;
      width:100%;
    }
  }
</style>

<TwicImg
  src="path/to/your/image"
  className="hero-image"
  ratio="none"
></TwicImg>

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Components Properties

TwicImg

This component is a drop-in replacement for the img tag dedicated to content images.

It offers advanced features like optimized Cumulative Layout Shift (CLS), Low-Quality Image Placeholder (LQIP), and lazy loading out of the box.

<TwicImg
  src="<path>"
  alt="<String>"
  anchor="<String>"
  bot="<String>"
  eager="<boolean>"
  focus="<auto|coordinates>"
  intrinsic="<String>"
  mode="<contain|cover>"
  position="<css position>"
  placeholder="<preview|maincolor|meancolor|none>"
  preTransform="<String>"
  ratio="<ratio>"
  bind:state="<String>"
  on:statechange="<function>"
  refit="<boolean|String>"
  step="<integer>"
  title="<String>"
  transition="<fade|zoom|none>"
  transitionDelay="<String>"
  transitionDuration="<String>"
  transitionTimingFunction="<String>"
  zoom="<String | Number>"
/>
AttributeDescriptionTypeDefault
altalt attribute contentString
anchorPositions the image in both contain and cover mode. Accepted values are top, bottom, left, right, top-left, top-right, bottom-left, bottom-right and center. position and focus take precedence in contain and cover mode respectively. Please note that anchor is applied after an eventual preTransform. When using refit in cover mode, anchor aligns the main object(s) with the given border side.String
botA slash-separated list of TwicPics API transformations to be performed for search engine bots. This overrides all other transformations when provided, even if empty (i.e bot=""). See the TwicPics bot attribute documentation for more information.String
eagerLoad the image as soon as the component is mounted. This effectively means disabling lazy loading for this image.booleanfalse
focusSets the focus point in cover mode. focus takes precedence over anchor when both are provided. See the TwicPics focus attribute documentation for more information. Only use this attribute if you need a specific focus point or if you want to leverage smart cropping with focus="auto": if you only need border-based positionning (top, bottom, left, right, etc), use anchor instead.String
intrinsicDimensions in pixels of the original image, formatted <width>x<height> (eg. 1920x1080). It prevents image upscaling and limits the number of generated variants. If using preTransform, you should specify the intrinsic dimensions of the resulting image. Using incorrect values can lead to display issues, see the intrinsic attribute documentation.String
modeCan be contain or cover and determines if the image fills the area and is cropped accordingly (cover) or if the image will sit inside the area with no cropping (contain).Stringcover
placeholderCan be preview, meancolor, maincolor or none. See the TwicPics output transformation documentation for more information. Setting will be overridden to none when using zoom transition.Stringpreview
positionPositions the image in contain mode. position takes precedence over anchor when both are provided. Syntax is the same as for CSS position properties background-position and object-position. Only use this attribute if you need precise positionning: if you only need border-based positionning (top, bottom, left, right, etc), use anchor instead.Stringcenter
preTransformA slash-separated list of TwicPics API transformations to be performed before resizing the image (see the TwicPics Manipulation documentation). Note that anchor and focus are applied after preTransform: if you need to specify a specific focus point for your preTransform then it needs to be part of the expression (like preTransform="focus=auto/crop=50px50p" for instance). Be aware that using this option can lead to unexpected results so use with caution!String
ratioA unitless width/height or width:height value pair (as in 4/3 or 4:3) that defines the aspect ratio of the display area. If height is not specified, it is assumed to be 1. A square area will be created by default. When set to none, ratio is determined based on width and height as computed by the browser following your CSS definitions. The --twic-ratio CSS variable is ignored in this instance. You are responsible for properly sizing the component when ratio="none".String or number1
refitReframes the image to maximize the area occupied by the main object(s) while respecting ratio in cover mode. Crops the image as close as possible to the main object(s) in contain mode. Can be true, false or a list of comma-separated length defining padding. See the TwicPics refit documentation for more information.boolean or Stringfalse
srcPath to the image. When not provided, a red lightweight svg placeholder that displays its intrinsic dimensions is displayed in place of the absent image. When env is set to offline, that red lightweight svg is replaced by a simple red placeholder.String
stateA string property being update each time the asset loading state is updated. Values can be new, loading, done or error.String
statechangeA custom event dispatched each time the image loading state is updated. Emitted values can be new, loading, done or error.( e: CustomEvent ) => void
stepSee the TwicPics step attribute documentation for more information.Integer10
titletitle representing information related to the image. See global attribute title.String
transitionDetermines how the image will be revealed once loaded. With a fade in effect (fade), a zoom effect (zoom) or without any transition (none). Unsupported values are handled as fade.Stringfade
transitionDurationDuration of the transition effect.String400ms
transitionTimingFunctionCSS timing function applied to the transition effect.Stringease
transitionDelayTransition delay of the transition effect.String0ms
zoomEnables zoom feature and sets the magnification factor. Must be a number strictly greater than 1 as in "1.5" or 1.5. When set to 'css', magnification factor is defined through the CSS variable --twic-zoom.Should only be applied to images in cover mode. See Image magnifier.`Stringnumber`

TwicPicture

This component serves as a seamless replacement for the picture element.

With a primary focus on maximizing the Largest Contentful Paint (LCP) score with optimized Cumulative Layout Shift (CLS), it effortlessly generates the srcset and source attributes for resolution switching and art direction, all derived from a single master file transformed through the TwicPics API.

<TwicPicture
  src="<path>"
  alt="<String>"
  anchor="<String>"
  eager="<boolean>"
  fetchpriority="<high|low|auto>"
  focus="<auto|coordinates>"
  mode="<contain|cover>"
  position="<String>"
  preTransform="<String>"
  ratio="<ratio>"
  refit="<boolean|String>"
  sizes="<String>"
  title="<String>"
/>
AttributeDescriptionTypeDefault
altalt attribute contentString
anchorPositions the image in both contain and cover mode. Accepted values are top, bottom, left, right, top-left, top-right, bottom-left, bottom-right and center. position and focus take precedence in contain and cover mode respectively. Please note that anchor is applied after an eventual preTransform. Can be set at different breakpoints.String
eagerLoad the image as soon as the picture element is processed and set fetchpriority to high. This effectively means disabling lazy loading for this image. Recommended for optimal Largest Contentful Paint (LCP) display.booleanfalse
fetchpriorityActs as standard fetchpriority property. Can be high, lowor auto. Defaults to high when eager is true.string
focusSets the focus point in cover mode. focus takes precedence over anchor when both are provided. See the TwicPics focus attribute documentation for more information. Only use this attribute if you need a specific focus point or if you want to leverage smart cropping with focus="auto": if you only need border-based positionning (top, bottom, left, right, etc), use anchor instead. Can be set at different breakpoints.String
modeCan be contain or cover and determines if the image fills the area and is cropped accordingly (cover) or if the image will sit inside the area with no cropping (contain). Can be set at different breakpoints.Stringcover
positionPositions the image in contain mode. position takes precedence over anchor when both are provided. Accepted values are top, bottom, left, right, top-left, top-right, bottom-left, bottom-right and center. Can be set at different breakpoints.Stringcenter
preTransformA slash-separated list of TwicPics API transformations to be performed before resizing the image (see the TwicPics Manipulation documentation). Note that anchor and focus are applied after preTransform: if you need to specify a specific focus point for your preTransform then it needs to be part of the expression (like preTransform="focus=auto/crop=50px50p" for instance). Be aware that using this option can lead to unexpected results so use with caution!String
ratioA unitless width/height or width:height value pair (as in 4/3 or 4:3) that defines the aspect ratio of the display area. If height is not specified, it is assumed to be 1. A square area will be created by default. When set to none, the image is displayed with its intrinsic aspect ratio. In this case, you are responsible for optimizing the Cumulative Layout Shift (CLS). Can be set at different breakpoints.String or number1
refitReframes the image to maximize the area occupied by the main object(s) while respecting ratio in cover mode. Crops the image as close as possible to the main object(s) in contain mode. Can be true, false or a list of comma-separated length defining padding. See the TwicPics refit documentation for more information.boolean or Stringfalse
sizesSpecifies the layout width of the image for each breakpoints using media query syntax. The value of this parameter has a significant impact on performance. Ensure to configure it carefully. See sizes.String
srcPath to the image.String
titletitle representing information related to the image. See global attribute title.String

TwicVideo

This component is a drop-in replacement for video.

It provides seamless playback for videos optimized with TwicPics, offering advanced features like optimized Cumulative Layout Shift (CLS), Low-Quality Image Placeholder (LQIP), and lazy loading out of the box.

<TwicVideo
  src="<path>"
  anchor="<String>"
  bot="<String>"
  duration="<String|number>"
  eager="<boolean>"
  from="<String|number>"
  focus="<auto|coordinates>"
  intrinsic="<String>"
  mode="<contain|cover>"
  position="<css position>"
  posterFrom="<String|number>"
  placeholder="<preview|maincolor|meancolor|none>"
  preTransform="<String>"
  ratio="<ratio>"
  bind:state="<String>"
  on:statechange="<function>"
  step="<integer>"
  title="<String>"
  to="<String|number>"
  transition="<fade|zoom|none>"
  transitionDelay="<String>"
  transitionDuration="<String>"
  transitionTimingFunction="<String>"
/>
AttributeDescriptionTypeDefault
anchorPositions the video in both contain and cover mode. Accepted values are top, bottom, left, right, top-left, top-right, bottom-left, bottom-right and center. position and focus take precedence in contain and cover mode respectively. Please note that anchor is applied after an eventual preTransform. When using refit in cover mode, anchor aligns the main object(s) with the given border side.String
botA slash-separated list of TwicPics API transformations to be performed for search engine bots. This overrides all other transformations when provided, even if empty (i.e bot=""). See the TwicPics bot attribute documentation for more information.String
durationLimits the duration of the video. duration is expressed in seconds and must be a positive number. duration will not move the starting point of the video: to do so, you'll have to use the from property. See duration documentation.String or number
eagerLoad the video as soon as the component is mounted. This effectively means disabling lazy loading for this video.booleanfalse
focusSets the focus point in cover mode. focus takes precedence over anchor when both are provided. See the TwicPics focus attribute documentation for more information. Only use this attribute if you need a specific focus point or if you want to leverage smart cropping with focus="auto": if you only need border-based positionning (top, bottom, left, right, etc), use anchor instead.String
fromMoves the starting point of the video. from is expressed in seconds and must be a positive number. from will not move the end point of the video: to do so, you'll have to use the duration or to properties. See from documentation. See from documentation.String or number
intrinsicDimensions in pixels of the original video, formatted <width>x<height> (eg. 1920x1080). It prevents video upscaling and limits the number of generated variants. If using preTransform, you should specify the intrinsic dimensions of the resulting video. Using incorrect values can lead to display issues, see the intrinsic attribute documentation.String
modeCan be contain or cover and determines if the video fills the area and is cropped accordingly (cover) or if the video will sit inside the area with no cropping (contain).Stringcover
placeholderCan be preview, meancolor, maincolor or none. See the TwicPics output transformation documentation for more information. Setting will be overridden to none when using zoom transition.Stringpreview
positionPositions the video in contain mode. position takes precedence over anchor when both are provided. Syntax is the same as for CSS position properties background-position and object-position. Only use this attribute if you need precise positionning: if you only need border-based positionning (top, bottom, left, right, etc), use anchor instead.Stringcenter
posterFromDetermines which frame of the source video should be used as a poster / preview. posterFrom is expressed in seconds and must be a positive number. By default posterFrom is equal to 0, meaning the very first frame of the video is used. posterFrom will not modify the video in any way: to do so, you'll have to use the duration, from or to properties.String or number
preTransformA slash-separated list of TwicPics API transformations to be performed before resizing the video (see the TwicPics Manipulation documentation). Note that anchor and focus are applied after preTransform: if you need to specify a specific focus point for your preTransform then it needs to be part of the expression (like preTransform="focus=auto/crop=50px50p" for instance). Be aware that using this option can lead to unexpected results so use with caution!String
ratioA unitless width/height or width:height value pair (as in 4/3 or 4:3) that defines the aspect ratio of the display area. If height is not specified, it is assumed to be 1. A square area will be created by default. When set to none, ratio is determined based on width and height as computed by the browser following your CSS definitions. The --twic-ratio CSS variable is ignored in this instance. You are responsible for properly sizing the component when ratio="none".String or number1
srcPath to the video. When not provided, a red lightweight svg placeholder that displays its intrinsic dimensions is displayed in place of the absent video. When env is set to offline, that red lightweight svg is replaced by a simple red placeholder.String
stateA string property being update each time the asset loading state is updated. Values can be new, loading, done or error.String
statechangeA custom event dispatched each time the image loading state is updated. Emitted values can be new, loading, done or error.( e: CustomEvent ) => void
stepSee the TwicPics step attribute documentation for more information.Integer10
titletitle representing information related to the video. See global attribute title.String
toMoves the end point of the video. to is expressed in seconds and must be a positive number. to will not move the starting point of the video: to do so, you'll have to use the from property. See to documentation.String or number
transitionDetermines how the video will be revealed once loaded. With a fade in effect (fade), a zoom effect (zoom) or without any transition (none). Unsupported values are handled as fade.Stringfade
transitionDurationDuration of the transition effect.String400ms
transitionTimingFunctionCSS timing function applied to the transition effect.Stringease
transitionDelayTransition delay of the transition effect.String0ms

CSS Variables

List of variables that can be used to configure your components using pure CSS:

<selector> {
  --twic-ratio: <ratio>;
  --twic-mode: <contain|cover>;
  --twic-position: <css position>;
  --twic-transition-delay: <string>;
  --twic-transition-duration: <string>;
  --twic-transition-timing-function:<string>;
  --twic-zoom:<number>;
}

Each CSS variable corresponds to one of the components attributes listed in the Components Properties section. If present, the attribute takes precedence over the corresponding CSS variable.

VariableDescriptionHTML AttributeDefault
--twic-modeCan be contain or cover and determines if the image fills the area and is cropped accordingly (cover) or if the image will sit inside the area with no cropping (contain).modecover
--twic-positionOnly useful in contain mode. Locates the image inside the area. Syntax is the same as for CSS position properties like background-position or object-position. Useful values are top, bottom, left, right, left top, left bottom and so on.positioncenter
--twic-ratioFloating point value corresponding to a unitless width/height ratio (as in calc(4/3) or 1.333). Ratio will correspond to a square area by default.ratio1
--twic-transition-delayTransition delay of the transition effect.transitionDelay0ms
--twic-transition-durationDuration of the transition effect.transitionDuration400ms
--twic-transition-timing-functionCSS timing function applied to the transition effect.transitionTimingFunctionease
--twic-zoomStrictly greater than 1 floating point value corresponding to the zoom factor to be applied. Only applies to TwicImg with zoom property set to "CSS".number

Default Breakpoints

There are six default breakpoints, each corresponding to common device resolutions:

BreakpointSize (pixels)
xs320
sm640
md768
lg1024
xl1280
2xl1536

These values are customizable during component configuration. Refer to Setup Options.

Feedback and support

TwicPics Components are open-source on GitHub. For features requests and bugs, open an issue. The TwicPics team also remains available for support via the live chat (at the bottom right.)

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