Object placement for Lens Studio

PlaceObjectOnSurface.js

/*

  REQUIRED: Create a ground plane with a collider 
  so we can hit test against it to place the object on the surface.

*/

/* API */
script.api.enablePlacement = function (bool) { placementEnabled = bool }
script.api.setScreenPoint = function (pt) { screenPoint = pt }

//@input SceneObject targetObject
/** @type {SceneObject} */
var targetObject = script.targetObject || script.getSceneObject()

//@input Component.DeviceTracking deviceTracking
/** @type {DeviceTracking} */
var deviceTracking = script.deviceTracking

//@input vec2 screenPoint = {0.5, 0.5} "Screen Point"
/** @type {vec2} */
var screenPoint = script.screenPoint

//@input bool lookAtCamera = true "Rotate to face camera"
/** @type {boolean} */
var lookAtCamera = script.lookAtCamera

//@input bool autoStart = true "Auto start"
/** @type {boolean} */
var autoStart = script.autoStart

//@input bool repositionWithTap = true "Reposition with tap"
/** @type {boolean} */
var repositionWithTap = script.repositionWithTap

//@input float lerpSpeed = 0.8 "Lerp Speed"
/** @type {number} */
var lerpSpeed = script.lerpSpeed

//@input bool debug = true "Debug"
/** @type {boolean} */
var debug = script.debug

//@input Physics.ColliderComponent groundCollider
/** @type {ColliderComponent} */
var groundCollider = script.groundCollider

var transform = targetObject.getTransform()
var camera = deviceTracking.getSceneObject().getComponent("Component.Camera")
var cameraTransform = camera.getTransform()

var placementEnabled = autoStart

var probe = Physics.createGlobalProbe()
probe.debugDrawEnabled = debug
probe.filter.onlyColliders = [groundCollider]

script.createEvent('UpdateEvent').bind(function () {
  if (!placementEnabled) return
  placeObjectOnSurface()
  if (lookAtCamera) rotateTowardCamera()
})

var touchStart = script.createEvent("TouchStartEvent")
touchStart.bind(function (eventData) {
  print(eventData.getTouchPosition())
  screenPoint = eventData.getTouchPosition()
})

function rotateTowardCamera() {

  // look at the camera
  var forward = cameraTransform.getWorldPosition().sub(transform.getWorldPosition()).normalize()
  forward.y = 0 // Remove Y-axis component to lock rotation to the Y-axis
  var newRotation = quat.lookAt(forward, vec3.up())
  transform.setWorldRotation(quat.slerp(newRotation, transform.getWorldRotation(), lerpSpeed))
}

function placeObjectOnSurface() {

  // Use raycast to find the surface
  const rayTarget = camera.screenSpaceToWorldSpace(screenPoint, 10000)
  var camPos = cameraTransform.getWorldPosition()
  probe.rayCast(camPos, rayTarget, function (hit) {
    if (!hit) return
    print(hit)

    // place the object on the surface
    var currentPosition = transform.getWorldPosition()
    transform.setWorldPosition(vec3.lerp(hit.position, currentPosition, lerpSpeed))
  })

  // NOTE only works for world tracking
  // do a hit test on the world mesh
  // var surfacePosition = deviceTracking.hitTestWorldMesh(screenPoint)
  // if (surfacePosition && surfacePosition[0]) {

  //   // place the object on the surface
  //   transform.setLocalPosition(vec3.lerp(surfacePosition[0].position, transform.getLocalPosition(), .8))

  //   if (lookAtCamera) {
  //     // look at the camera
  //     var newRotation = quat.lookAt(cameraTransform.getWorldPosition().sub(transform.getWorldPosition()), vec3.up())
  //     newRotation = new quat.fromEulerAngles(0, newRotation.toEulerAngles().y, 0) // NOTE locking the x and z rotation
  //     transform.setWorldRotation(quat.slerp(newRotation, transform.getWorldRotation(), .8))
  //   }
  // }
}