Disposes of any Three.js object and any disposal objects in the hierarchy below it by doing a depth-first search

threejs-hierarchy-disposal.js

/**
 * Disposes of any Three.js object (mesh, material, etc.) and any disposable objects in the hierarchy below it by doing a depth-first search.
 * @param {Boolean} showLogging Output logs useful for troubleshooting.
 * @example
 *   const trash = HierarchyDisposal(true)
 *   trash([some three.js object])
 */

function HierarchyDisposal (showLogging = false) {
  const bag = []
  const ignoreKeys = [
    '_super',
    'parent'
  ]

  const dispose = (obj, ondone) => {
    const id = obj.uuid
    const name = obj.name || id || obj
    if (bag.includes(id)) return
    if (showLogging) console.log('calling dispose on', name)

    for (var key in obj) {
      const childObj = obj[key]
      if (
        obj.hasOwnProperty(key) &&
        !ignoreKeys.includes(key) && 
        childObj && 
        typeof childObj === 'object'
      ) dispose(childObj)
    }
    if (typeof obj.dispose === 'function' && obj.uuid) {
      if (showLogging) console.log('disposing of', name)
      obj.dispose()
      bag.push(id)
    }
    if (typeof ondone === 'function') ondone(bag)
  }
  
  return dispose
}