# Using the SDK

## Streaming 3D assets into Unity

Let's start with something simple.

1. Open the `Prefabs` folder within the `echo3D Unity SDK` package folder and add the `Echo3DService` prefab to any scene where you wish to load assets.

![](/files/E3JPxzSnfySiDN1w68rh)

2\. Add the `Echo3DHologram` prefab from the same folder to your scene. 

This is an empty game object with the `Echo3DHologram.cs` script attached to it.

You can also simply add the `Echo3DHologram.cs` script to any existing game object.

<figure><img src="/files/AJqFY3dgDd9CLIqa5pPH" alt=""><figcaption></figcaption></figure>

3\. In the Inspector View for the game object with the `Echo3DHologram.cs` script, update the `API Key` field with your [API key](/quickstart/get-api-key.md).

![](/files/6RF9CdL9p3ZMWEukviBA)

Your `API Key` and `Entry ID` can be found in your console:

<figure><img src="/files/uKyqSMN9L5AQAu394LoK" alt=""><figcaption></figcaption></figure>

4\. Type your [Secret Key](/web-console/manage-pages/collections-and-sharing/security.md#secret-key) as the value for the parameter `secKey` in the file `Packages/co.echo3D.unity/Runtime/Echo3DHologram.cs`.

{% hint style="warning" %}
This is applicable only if you have the [Secret Key](/web-console/manage-pages/collections-and-sharing/security.md#secret-key) option enabled.
{% endhint %}

![](/files/5q1e7gc8uswU9cGtaDhX)

5\. [Add a 3D model](/quickstart/add-a-3d-model.md) through the [console](https://console.echo3D.co). Here's how:

{% content-ref url="/pages/-M41tDLv3LlxH4e-G\_ou" %}
[Add a 3D Asset](/quickstart/add-a-3d-model.md)
{% endcontent-ref %}

![](/files/YAk6dv5pfZ87PdNLKzAI)

6\. Go back to Unity and hit the **Play** button.

The SDK will stream the 3D model into Unity.

![](/files/9pwmq0NhPw7Vopxuas7o)

**All done!** 🎉

### Video Tutorial

Here's a tutorial that can guide you through the steps shown above:

{% embed url="<https://youtu.be/98bebj0g674>" %}

## Viewing the demo scene

The SDK includes a robust demo scene preconfigured to load assets (models, images, and videos) from our platform. Follow these steps to run the scene:

1. In the top menu, click `Window` and then `Unity Package Manager`.
2. Add the scene to your project by importing the package samples via the Unity Package Manager. Under `Packages - echo3D` select `echo3D Unity SDK` and click Import on the right side of the screen.

<figure><img src="/files/1RN2MPrfFhZrRui0VD4e" alt=""><figcaption></figcaption></figure>

2\. A `Samples` folder will be created within your project `Assets`folder. Open the `Echo3DDemo`scene.

<figure><img src="/files/yewN7Ydn2xE6QDcYzuqw" alt=""><figcaption></figcaption></figure>

3\. Press "Play" to run the demo scene. Assets will stream and instantiate within the scene. **Note: An internet connection is required.**&#x20;

<figure><img src="/files/G4pQGr3krAG1r0hI0OAm" alt=""><figcaption></figcaption></figure>

**All done!** 🎉


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