vuexr

VueXR

VueXR is a Vue plugin that let's you project regular DOM components onto augmented reality (AR) markers in real-time.

It is just as easy as:

<ar-view>
  <ar-element :id="23">
    <div class="hello">Hello World!</div>
  </ar-element>
</ar-view>

With VueXR, you are able to build an AR-Prototype in minutes using your existing 2D web-application. There is no need for you to dive into complex and hard to understand computer graphic topics – just use your web development skills!

To achieve such functionality, VueXR uses OpenCV.js, CSS-Transforms, Sensor API and Web Workers API on a picture stream from your device's camera. Have a look at our sources or contact me at [e-mail] or at https://technokrat.ch

Inspiration

Why AR?

Industry

Imagine, you could wander through an industrial hall with your smartphone, and directly see real-time sensor readouts hovering in 3D over the machinery. With a simple touch press you then open up a detailed view.

You do not have to scroll through infinite pages of SCADA units on your computer in search for the specific machinery – You are now directly linked via the physical entity itself.

Leaving you more ease-of-access, you benefit from less cognitive demand, so you can do your job more efficient. Maybe you can even identify a failing component in advance, saving your company a lot.

Home Entertainment

You are a small company offering custom upper-class smarthome & home entertainment solutions. You want to offer your customers a custom User Interface with next-generation features. With VueXR you can combine many already-existing web-solutions into one surface. No problem for VueXR!

Why VueXR?

Conventional AR requires a lot of expertise in building native smartphone applications for a multitude of platforms, requiring hard to get specialists.

For small and large businesses this poses a very large financial and personnel undertaking, while having bad time to market performance.

In contrast, VueXR allows you to prototype a solution in no time, by leveraging the ease, accessibility, and mutli-platform capabilities of modern web technologies, as well as your existing web codebase: You only have to write your code once!

Why Technokrat?

Technokrat is a full-stack engineering service by ETH-alumni in Zurich, Switzerland, and is the maintainer behind VueXR.

Our strength lies in the combination of research, electronics design, firmware, IoT, computer engineering, manufacturing, and software development.

We can offer you a one-stop experience in upgrading (legacy) setups to AR, or start from the beginning, and consult you and your team in bootstraping and selecting the best competitive solution. We also integrate Web-APIs directly into your existing software (such as REST, GraphQL, SOAP, Swagger, etc.). Just give us a call and we support you with a workshop or MVP in just under six weeks.

Getting Started

First install the vuexr npm package.

npm install vuexr

# or
# yarn add vuexr

Then add VueXR to your index.ts (or index.ts)

import Vue from 'vue';

// Import the VueXR plugin
import { VueXR } from 'vuexr';
// or const Vuexr = require('vuexr');

// Install the VueXR plugin
Vue.use(VueXR);

// Initialize your application
const app = new Vue({
    // …
});

Add the following inside your preferred component (e.g. App.vue)

<template>
    <ar-view>
      <ar-element :id="23">
        <div class="hello">Hello World!</div>
      </ar-element>
    </ar-view>
</template>

<script>
  import Vue from 'vue'

  const App = Vue.extend({
    name: 'app',
  });

  export default App;
</script>

<style>
  .hello {
    position: absolute;
    box-sizing: border-box;
    width: 50px;
    height: 50px;
    background: rgba(255,255,255,0.9);
    padding: 10px;
    font-size: 10px;
  }
</style>

You need to copy the opencv_js.wasm and worker.js file to your static/public folder (where your deployed index.html is located). See the demo.webpack.config.js for inspiration.

You are now ready to test the application with a smartphone. Remember that you have to connect via HTTPS or localhost for VueXR to work. Accept the camera permission request.

Calibration

For each new device we first need to calibrate the camera (i.e. automatically calculate the focal length), to project our DOM elements with the correct perspective. Just open this chessboard pattern on a different screen, and try to fit all chessboard fields into the camera's view. VueXR will highlight the chessboard's intersection points. Press the red Capture Frame button, and repeat this around eight times for different perspectives. Press the Calibrate button when you are finished. You are now ready to detect the ArUco markers.

Usage

Performance

You have to use a state of the smartphone plattform, such as a Xiaomi 20K / 9T Pro with MIUI 11, as computer vision takes it's fair share of processing power.

General

In general, you only require two new components to use VueXR

• <ar-view> is our wrapper around the AR-session. It does initialize all required components for computer vision, camera, and position tracking. It can contain arbitrarily many <ar-element>'s
• <ar-element> is the container around the content rendered onto a ArUco marker.
  • The id attribute (of type Number) is required and assigns a unique ArUco identifier.
  • The timeout attribute (of type Number in milliseconds, default 1000) sets the time, a <ar-element> vanishes after it is not detected by the camera anymore
  • (NOT SUPPORTED) The markerSize attribute (of type Number in millimeters, default 50) sets the size of the respective ArUco marker, for precise projection.

Markers

VueXR can detect 6x6 ArUco markers up to decimal ID 250. The are quite robust, and encode orientation and identity in one. Use this generator webpage to print out a marker and stick it onto your toaster!

An <ar-element>'s origin is based in the middle of the marker. Use absolute positioning or CSS transforms to correctly align the content.

Nested Transformations

You might use nested transformations inside your <ar-element>'s content, e.g. transform3d(10px, 20px 30px). Ensure to set the CSS attribute transform-style to preserve-3d for all nested elements.

Tracking State & Animations

By default, if a <ar-element> times out due to not being tracked anymore, it will fade out and it's content removed from the DOM. See (https://vuejs.org/v2/guide/transitions.html#Transitioning-Single-Elements-Components).

If you want to handle things yourself, VueXR offers you a way to check if an <ar-element> is tracked from inside your <ar-element>'s content using Scoped Slots

Just use the following pattern to access the tracked property for a given <ar-element>:

<ar-view>
  <ar-element :id="50" v-slot:="{tracked}">
    <div class="hello" :class="{tracked: tracked}">
      Hello World!
    </div>
  </ar-element>
</ar-view>

Of course you are free to assign tracked to a sub-components property, use it for conditional rendering, and other fun stuff (VueXR fully supports the reactive features of Vue).

To animate the content based on the tracked state, you are free to use CSS transitions and/or animations. E.g. you could write

<style>
  .hello {
    position: absolute;
    background-color: rgba(255,255,255,0.9);
    transition: background-color 0.3s, color 0.3s;
  }

  .hello.tracked {
    background-color: red;
    color: white;
  }
</style>

Sizing

One millimeter (mm) in real-world matches one pixel (px) in your <ar-element>, plain and simple.

Demo

Clone this repository and run

yarn install
yarn run demo:serve

You can now access a demo application of VueXR under http://localhost:9000. To see some AR-content point your camera onto AruCo markers with ID 23 and 50.

Contribution

Future Work

• Compile OpenCV.js with WebAssembly SIMD support
• Move calibration to web worker
• Rewrite JS to TypeScript and code cleanup
• Documentation and Webpage (incl. Demo)
• More responsive position tracking
• DOM-Rendering in WebXR API
• Marker Scheme ID Attributes (allowing for future proof support of other marker systems)
• CI and Test Coverage

If you are interested in supporting this project contact me at [e-mail]

License

MIT

Copyright (c) 2020. Markus Wegmann, Technokrat LLC.

Technokrat LLC and the developers of VueXR are not liable for any damages in relation to the use or installment of VueXR.