Hoe can I build a 3d scanner?

To build a 3D scanner, you can leverage Apple's Object Capture technology, which was discussed in the session Discover area mode for Object Capture at WWDC 2024. Here are the steps you can follow:

Use the Sample App: Start by using the sample app provided by Apple. Open the app and select area mode. Aim at your subject and tap start capture. You'll receive haptic feedback, hear a tone, and see a pulse in the capture preview as images are taken. Ensure you move slowly and capture images that overlap with one another.
Capture Images: The reticle acts as a brush, and you can move it across surfaces to capture all the details. For best results, capture parallel to each surface of your subject. When done, check the camera pose visualization to ensure you have all the necessary data.
Process the 3D Model: After capturing, choose the process option to create a 3D model directly on your iPhone. For better quality, you can use the macOS sample app provided by Apple.
Integrate Area Mode: To integrate area mode into your own applications, you can use the new iOS API. Aim for diffuse lighting with no harsh shadows, move around slowly in regular paths, and capture from multiple heights to ensure every angle of your subject is covered.
Use the Data Loading API: For more flexibility, you can use the new data loading API introduced by Apple.

For more detailed instructions and to see a demo, you can watch the session Discover area mode for Object Capture.

Additionally, if you need to create a 3D model for object tracking, you can use the Object Capture technology to obtain a photorealistic 3D model. This is discussed in the session Explore object tracking for visionOS.

Here are the relevant sessions mentioned:

If you have any specific questions or need further details, feel free to ask!