> For the complete documentation index, see [llms.txt](https://reach-cloud.gitbook.io/reach-explorer-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://reach-cloud.gitbook.io/reach-explorer-documentation/metaverse-cloud-engine-sdk/unity-engine-sdk/ar-experiences.md).

# AR Experiences

Reach Cloud supports AR experiences using our Meta Prefab pipeline and our custom `https://ar.reachcoud.org` domain.

## Guide

1. Begin by following the documentation on uploading Prefabs using [Reach’s Cloud Engine SDK](https://reach-cloud.gitbook.io/reach-explorer-documentation/metaverse-cloud-engine-sdk/unity-engine-sdk/upload-a-prefab). <mark style="color:red;">**You must upload for WebGL**</mark> since this is a Web Based application. Other platforms will be ignored.
2. After successfully uploading a prefab, you’ll want to begin by constructing a link. Please follow the [parameters](#ar-url-parameters) section for details.
3. Take the final URL and create a QR code out of it. You may use the QR code itself as the tracked image by uploading it as the Meta Prefab thumbnail (but don’t include the `imageurl` parameter)
4. After following these steps you should have a working AR experience like the example below.<br>

[Example AR Demo](https://www.youtube.com/shorts/PNZWhZgeG9Y)

## AR URL Parameters

Below is a table showing the parameters you can specify in the <https://ar.reachcloud.org> URL to configure the AR experience.

<br>

| Name (exact spelling and capitalization required) | Required | Type                                                           | Example                                       | Description                                                                                                                                                                                                          |
| ------------------------------------------------- | -------- | -------------------------------------------------------------- | --------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| prefabId                                          | Yes      | GUID                                                           | prefabId=fb0f9b66-4287-49e3-9e55-a154b8b48851 | The ID of the [Meta Prefab](https://reach-cloud.gitbook.io/reach-explorer-documentation/metaverse-cloud-engine-sdk/unity-engine-sdk/components/assets/meta-prefab) that should load when the tracked image is found. |
| imageUrl                                          | No       | <p>Image URL (Encoded)</p><p><br></p><p>Must be PNG or JPG</p> | imageUrl=https%3A%2F%2Fpicsum.photos%2F200    | <p>The (url encoded) URL to the image to use as a tracked image.</p><p><br></p><p>If this value is not specified, the Prefab’s thumbnail will be used as the tracked image.</p>                                      |
| persistent                                        | No       | Number: 0 or 1                                                 | persistent=1                                  | If 1, then the loaded prefab will remain on-screen even when the tracked image is lost. Otherwise the prefab will only appear when the tracked image is visible to the camera.                                       |

Example URL:&#x20;

[https://ar.reachcloud.org?prefabId=fb0f9b66-4287-49e3-9e55-a154b8b48851\&imageUrl=https%3A%2F%2Fpicsum.photos%2F200\&persistent=0](https://ar.reachcloud.org?prefabid=fb0f9b66-4287-49e3-9e55-a154b8b48851\&imageurl=https%3A%2F%2Fpicsum.photos%2F200\&persistent=0)


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