How to use WebXR?

Answered by Robert Dupre

To use WebXR, you’ll need a compatible device such as a smartphone or a VR headset, and a web browser that supports WebXR. Currently, Chrome, Firefox, and Microsoft Edge are the most popular browsers that support WebXR. Once you have the required setup, you can start creating an immersive AR session using WebXR.

1. Remove the demo cube:
When starting an AR session, many WebXR demos include a default cube or object in the scene. To remove this, you can simply delete the code that generates the cube or replace it with your own content.

2. Use the hit-test feature:
The hit-test feature in WebXR allows you to place virtual objects in the real world by detecting surfaces or points in the environment. This is done by using the hitTest API provided by WebXR. To use the hit-test feature, you’ll need to enable the appropriate XR session options and listen for hit test events.

3. Add a model loader:
To load 3D models into your AR session, you’ll need a model loader that supports GLTF format. GLTF (Graphics Library Transmission Format) is a common file format for 3D models that is lightweight and optimized for the web. There are several libraries available for loading GLTF models, such as Three.js or A-Frame.

4. Load GLTF models:
Once you have a model loader set up, you can load GLTF models into your AR scene. You’ll need to provide the URL or file path of the GLTF model, and the loader will handle the loading and rendering of the model. Make sure to position and scale the model appropriately in the AR scene.

5. Create a hit test source:
To perform hit tests in WebXR, you’ll need to create a hit test source. This is done by calling the `createHitTestSource` method on the XR session. The hit test source provides a way to query the XR device for hit test results. You can then use these results to place virtual objects in the real world.

6. Drawing a targeting reticle:
To provide a visual indicator for the user during hit testing, you can draw a targeting reticle on the screen. This can be done using HTML and CSS or by rendering a 2D sprite in the AR scene. The reticle should follow the user’s gaze or pointer and provide feedback when a hit test is successful.

7. Adding interactions on tap:
To enhance the AR experience, you can add interactions when the user taps or clicks on virtual objects. This can be done by listening for input events and performing actions based on the user’s interaction. For example, you can animate the object, change its color, or trigger a sound effect.

8. Test the hit test:
Before deploying your AR application, it’s important to thoroughly test the hit test feature on different devices and in various environments. Make sure that the virtual objects are placed accurately and that they align correctly with the real-world surfaces. Consider factors such as lighting conditions, surface textures, and device limitations.

Remember, creating an immersive AR session using WebXR requires a combination of JavaScript, HTML, and CSS skills, as well as knowledge of 3D graphics and rendering. It’s a continuous learning process, and you may encounter challenges along the way. Don’t hesitate to explore documentation, online resources, and communities for guidance and support. Happy coding!