WebXR and <model-viewer>
WebXR is an evolutionary development of the old WebVR APIs that addresses user feedback and additional use cases that were not available when the original WebVR APIs were created.
The Immersive Web Community Group expects the final WebVR compatible draft to be released this summer (2019) and the candidate recommendation with two interoperable implementations to be released towards the end of the year.
While we wait for the WebXR specification to solidify, we can play with libraries that abstract some of the underlying complexities of WebVR, WebXR, and the basic Three.js library.
<model -viewer> #
An interesting tool I saw at SFHTML5 is
model-viewer, a web component-based tool that will display 3D content in a 2D hosting page.
model-viewer provides a way to view 3D content in a web browser, independently of the form factor you're using (either a 2d Desktop browser or the browser built into a 3D device like the Oculus Quest). It is a web component so we need to polyfill web components for older versions of Edge and Firefox.
In the video below, Chris Joel, from the DeviceXR at Google explains
model-viewer, what it is and how it works.
This assumes that we've loaded the polyfills using NPM. This is not an absolute requirement. You can always load the script from a CDN but, I prefer to have the scripts in my local directory
npm i @google/model-viewer \
I normally put the scripts at the bottom of the page, before the closing body tag and before loading the model viewer scripts.
webcomponents-loader is required to support older
versions of Edge and FIrefox
Fullscreen polyfill is required for experimental
AR features in Canary
Magic Leap support
After we load the polyfills, we can load the
model-viewer scripts. We use modules to load the scripts in modern browsers and
nomodule to load a different script for those browsers that don't support modules.
<script type="module" src="./js/model-viewer.js"></script>
<script nomodule src="./js/model-viewer-legacy.js"></script>
Once we have all the scripts installed we can use
model-viewer by creating one or more instances of the custom element like shown in the example below:
alt="A 3D model of a 2 cylinder"
You can have as many instances of
model-viewer as you need on your page. They can each be customized independently from each other. The two additional instances have different background colors. They can also be manipulated separately.
We can also load multiple models
But the more intriguing, to me, the thing about
model-viewer is how, with a few extra attributes you can provide a range of experiences, from mouse manipulation as shown in the prior examples to full support for Google's ARCore, Apple's Quicklook (with some additional requirements), and Magic Leap.
The code now looks like this:
The model won't look any different in desktop or devices where Scene Viewer is not supported but, in devices where the feature is supported, users will have an option to click on to place an interact with the object.
If you have the USDZ model, you can add it to your experience using the
ios-src attribute and the URL to the model.
And, of course, you can provide support for both, using
ios-src together to cover both Android and iOS in the same element
Final Notes #
This barely begins to scratch the surface of what we can do with
model-viewer.For more information see the [model-viewer documentation and this 2018 post about Augmented reality for the web that talks about the ideas that led to
Usdz is the wrinkle in the process. Most of the models in this page are loaded from glTF files, an interchange format created by the Khronos Group and that has wide support in terms of tools and technologies. As pointed out in All about Apple’s new USDZ File Format — Simplified the technology was developed by a single vendor, and has no open source tool support but there is commercial support, bot from small companies like Vectary and large tool companies like Adobe with Project Aero.
For more information about UDSZ, you can check the following resources.
- Usdz File Format Specification
- All about Apple’s new USDZ File Format — Simplified
- Apple's USDZ AR file format: What you need to know
- What is USDZ and why you should care - Apple's AR kit explained
Finally, I've made a copy of this page in Github where you can play with the working demos and test with Android and iOS: https://caraya.github.io/model-viewer-demo/index.html