encantar-js/docs/addons/ar-video-player.md

Video Player

An A-Frame component and primitive for playing videos in AR. <ar-video-player> is tailored for encantar.js. Unlike A-Frame’s standard <a-video>, <ar-video-player> handles corner cases for AR and includes easy-to-use controls, so you can focus on creating your projects rather than dealing with the various technicalities and quirks of video playback in the browser.

!!! tip “It’s easy to use!”

The Video Player Add-On includes a working demo that you can easily modify. This page documents it in depth and is meant to be used as a reference.

Properties

Property	Description	Default
src	Query selector of a <video> element.	""
autoplay	Whether or not the video should play as soon as the target is found. When enabling autoplay, your <video> element should be muted in order to comply with browser policies. Since: 1.1.0	false
width	Width of the player.	2
height	Height of the player.	1.125

!!! tip

Place your `<video>` tag(s) inside `<a-assets>`:

```html
<ar-root>
    <ar-video-player src="#my-video">
        <!-- ... video controls ... -->
    </ar-video-player>
</ar-root>

<!-- ... -->

<a-assets>
    <video id="my-video" playsinline>
        <source src="assets/my-video.mp4" type="video/mp4" />
        <source src="assets/my-video.webm" type="video/webm" />
    </video>
</a-assets>
```

!!! info “Aspect ratio”

Make sure that the `width` and the `height` of your `<ar-video-player>` match the aspect ratio of your video. The default size is appropriate for the commonly used 16:9 widescreen ratio.

Video controls

Overview

You may attach the ar-video-control component to any AR Button (typically) or to any AR Clickable (in general) in order to let the user control the video with a click. What exactly happens with a click depends on the selected action.

Add the ar-video-control component to a descendant of <ar-video-player> as in this example:

<ar-video-player src="#my-video">

    <!-- The play button is placed inside ar-video-player -->
    <ar-button id="play-button" position="0 -0.9 0"
        ar-video-control="action: play"
    ></ar-button>

</ar-video-player>

Properties

Property	Description	Default
action	The action to be performed.	""

Actions

Action	Description
"play"	Play the video.
"pause"	Pause the video.
"toggle"	Toggle the video playback.
"stop"	Pause and rewind the video.
"rewind"	Rewind the video without pausing it.
"mute"	Mute the video.
"unmute"	Unmute the video.
"toggleAudio"	Toggle the audio.
""	Do nothing.

Multiple videos

You may play different videos depending on the target that is being tracked. This can be accomplished by setting an <ar-video-player-source> for each reference image as in the example below:

<ar-root>
    <ar-video-player width="2" height="1.125">

        <!-- Set different videos for different targets -->
        <ar-video-player-source reference-image="mage" src="#mage-video"></ar-video-player-source>
        <ar-video-player-source reference-image="cat" src="#cat-video"></ar-video-player-source>

    </ar-video-player>
</ar-root>

Since: 1.1.0

Properties

Property	Description	Default
reference-image	The name of a reference image.	""
src	Query selector of a <video> element.	""

Declarative handlers

Overview

Declarative event handlers are components used to register event listeners that set properties. They provide an easy way to create interactivity within your HTML page. There is a component for each event:

Handler	Description
ar-onvideoplay	Triggered when the video is played.
ar-onvideopause	Triggered when the video is paused.
ar-onvideoended	Triggered when the video reaches its end.

These handlers can be added to <ar-video-player> itself or to any of its descendants:

<!-- Make the video player translucent when not playing a video -->
<ar-video-player src="#my-video" transparent="true" opacity="0.5"
    ar-onvideoplay="opacity: 1"
    ar-onvideopause="opacity: 0.5"
    ar-onvideoended="opacity: 0.5"
>
    <!-- ... video controls ... -->
</ar-video-player>

Video controls may be combined with declarative handlers for easy customization:

<!-- Make the pause button appear when the video starts playing.
     Make it disappear when the video ends or is paused. -->
<ar-video-player src="#my-video">

    <!-- The pause button is placed inside ar-video-player -->
    <ar-button id="pause-button" position="0 -0.9 0"
        visible="false" enabled="false"
        ar-onvideoplay="visible: true; ar-button.enabled: true"
        ar-onvideopause="visible: false; ar-button.enabled: false"
        ar-onvideoended="visible: false; ar-button.enabled: false"
        ar-video-control="action: pause"
    ></ar-button>

</ar-video-player>

Special properties

The following special properties are used to further customize the declarative handlers:

Property	Description
_target	Query selector to be used when setting properties on a different entity.
_delay	Delay, in milliseconds, before setting the properties.

!!! question “What about event-set?”

Declarative handlers are similar to A-Frame's event-set in their usage, but there are differences behind the scenes. Whenever working with the Video Player, usage of the declarative handlers presented in this page is recommended.

Multiple handlers

Use double-underscores (__) to attach multiple handlers of the same type to a single entity:

<!-- Make two animated characters show up as soon as the video reaches its end -->
<ar-video-player src="#my-video"
    ar-onvideoended__1="_target: #animated-character-1; visible: true"
    ar-onvideoended__2="_target: #animated-character-2; visible: true"
>
    <!-- ... video controls ... -->
</ar-video-player>

<!-- ... -->

<a-entity id="animated-character-1" visible="false" ... ></a-entity>
<a-entity id="animated-character-2" visible="false" ... ></a-entity>

Events

The <ar-video-player> emits the following events based on the state of the underlying <video> element:

Event name	Description
"videoplay"	Triggered whenever the video is played.
"videopause"	Triggered whenever the video is paused.
"videoended"	Triggered whenever the video reaches its end.

Methods

Method	Description
invoke(action)	Perform an action.

Autoplay

Due to browser policies, there are restrictions to be aware of when using autoplay:

• Usage of the autoplay setting on <ar-video-player> should be accompanied by a muted attribute on the <video> tag. If the page receives no user interaction, then you may only play your video automatically if it’s muted.
• Usage of the autoplay attribute on the <video> tag is discouraged. Video playback may be blocked. In addition, the Video Player will not show up in AR at the exact moment the page is loaded.
• Ponder whether or not playing an initially muted video makes sense for your project. It may be better to wait for user input in order to initiate the playback, e.g., have the user click on a play button. If you decide to use autoplay, have a unmute button nearby.

Example

<ar-root>
    <ar-video-player src="#my-video" autoplay="true">
        <!-- ... video controls ... -->
    </ar-video-player>
</ar-root>

<!-- ... -->

<a-assets>
    <!-- Notice the muted attribute -->
    <video id="my-video" playsinline muted>
        <source src="assets/my-video.mp4" type="video/mp4" />
        <source src="assets/my-video.webm" type="video/webm" />
    </video>
</a-assets>