AR Compiler

Compiles HoloScript to browser-native Augmented Reality via WebXR — placing HoloScript spatial objects in the physical world through the device camera, with no app download required.

Overview

The AR compiler (--target ar) generates a WebXR immersive-ar session application aligned with the WebXR Device API. It works on any AR-capable device browser:

Android Chrome (ARCore)
iOS Chrome / Safari (via WebXR viewer or Safari 17+)
Meta Browser (Quest passthrough)

This differs from the platform-specific compilers (iOS ARKit, Android ARCore) by targeting the browser layer — no Xcode, no Android Studio, instant deployment via URL.

bash

holoscript compile experience.holo --target ar --output ./web/

Output Structure

web/
  index.html        # WebXR entry point
  ar-bundle.js      # Compiled scene + AR logic
  assets/           # 3D models, textures
  manifest.json     # PWA manifest for home-screen install

Trait → AR Behaviour

HoloScript Trait	AR Behaviour
`@anchor`	World-locked via hit test
`@plane_detected`	Surface detection + snapping
`@collidable`	Mesh occlusion against real surfaces
`@tracked`	6DOF pose tracking
`@grabbable`	Touch/pinch to move in AR
`@pointable`	Gaze/screen-tap selection
`@spatial_audio`	3D positioned audio

Example

holo

composition "FurniturePlacer" {
  template "Chair" {
    @anchor
    @plane_detected
    @grabbable
    @collidable

    geometry: "model/chair.glb"
    scale: [1, 1, 1]

    on_place {
      this.locked = true
      ui.show("Chair placed! Tap to move.")
    }

    on_grab {
      this.locked = false
    }
  }

  logic {
    on_plane_detected(plane) {
      if (plane.label == "floor") {
        ui.show_reticle(plane.center)
      }
    }

    on_tap {
      spawn "Chair" at reticle.position
    }
  }
}

Compiler Options

Option	Default	Description
`--ar-occlusion`	`false`	Enable depth-based real-world occlusion
`--ar-lighting`	`true`	Match ambient light to real environment
`--ar-plane-types`	`floor,table`	Plane types to detect
`--ar-hit-test`	`true`	Enable tap-to-place
`--ar-dom-overlay`	`true`	Allow HTML UI overlaid on camera
`--ar-depth-sensing`	`false`	Enable raw depth data (ARCore only)

Progressive AR (No Headset Needed)

The AR output degrades gracefully:

Capability Available	Experience
WebXR immersive-ar	Full AR with camera passthrough
WebXR inline	3D viewer on flat screen
No WebXR	Static 3D model viewer (Three.js)

Device Compatibility

Device/Browser	Mode	Notes
Android Chrome (ARCore)	Full immersive-ar	Best experience
iOS Safari 17+	Limited immersive-ar	Hit test + anchors
iOS WebXR Viewer	Full immersive-ar	Via Mozllia WebXR Viewer app
Meta Quest (browser)	Passthrough AR	`--ar-occlusion` not supported
Desktop Chrome	Inline 3D only	Graceful fallback

AR Compiler ​

Overview ​

Output Structure ​

Trait → AR Behaviour ​

Example ​

Compiler Options ​

Progressive AR (No Headset Needed) ​

Device Compatibility ​

See Also ​