Dereference prefabs (#10222)

* move default prefabs into assets folder of default-project

* add authoring hook system and use to dereference prefabs on load

* licensing

* rename authoring hook state file

packages/editor/src/functions/EditorControlFunctions.ts

@@ -259,9 +259,9 @@ const createObjectFromSceneElement = (
   beforeEntity?: Entity
 ) => {
   const scenes = getSourcesForEntities([parentEntity])
-  const entityUUID =
+  const entityUUID: EntityUUID =
     componentJson.find((comp) => comp.name === UUIDComponent.jsonID)?.props.uuid ?? generateEntityUUID()
-
+  const sceneIDUsed = Object.keys(scenes)[0]
   for (const [sceneID, entities] of Object.entries(scenes)) {
     const name = 'New Object'
     const gltf = GLTFSnapshotState.cloneCurrentSnapshot(sceneID)
@@ -331,9 +331,9 @@ const createObjectFromSceneElement = (
       }
       parentNode.children.splice(beforeIndex, 0, nodeIndex)
     }
-
     dispatchAction(GLTFSnapshotAction.createSnapshot(gltf))
   }
+  return { entityUUID, sceneID: sceneIDUsed }
 }
 
 /**

packages/editor/src/functions/addMediaNode.ts

@@ -33,6 +33,7 @@ import { Entity, EntityUUID } from '@etherealengine/ecs/src/Entity'
 import { defineQuery } from '@etherealengine/ecs/src/QueryFunctions'
 import { AssetLoaderState } from '@etherealengine/engine/src/assets/state/AssetLoaderState'
 import { PositionalAudioComponent } from '@etherealengine/engine/src/audio/components/PositionalAudioComponent'
+import { addAuthoringHook } from '@etherealengine/engine/src/gltf/AuthoringHookState'
 import { ImageComponent } from '@etherealengine/engine/src/scene/components/ImageComponent'
 import { MediaComponent } from '@etherealengine/engine/src/scene/components/MediaComponent'
 import { ModelComponent } from '@etherealengine/engine/src/scene/components/ModelComponent'
@@ -48,7 +49,6 @@ import { ObjectLayerComponents } from '@etherealengine/spatial/src/renderer/comp
 import { ObjectLayers } from '@etherealengine/spatial/src/renderer/constants/ObjectLayers'
 import { MaterialComponent, MaterialComponents } from '@etherealengine/spatial/src/renderer/materials/MaterialComponent'
 import { getMaterial } from '@etherealengine/spatial/src/renderer/materials/materialFunctions'
-
 import { EditorControlFunctions } from './EditorControlFunctions'
 
 /**
@@ -122,6 +122,21 @@ export async function addMediaNode(
           before
         )
       })
+    } else if (contentType.startsWith('model/prefab')) {
+      const { entityUUID, sceneID } = EditorControlFunctions.createObjectFromSceneElement(
+        [{ name: ModelComponent.jsonID, props: { src: url } }, ...extraComponentJson],
+        parent!,
+        before
+      )
+      addAuthoringHook({
+        entityUUID,
+        sceneID,
+        callback: (entityUUID) => {
+          const entity = UUIDComponent.getEntityByUUID(entityUUID)
+          const modelComponent = getMutableComponent(entity, ModelComponent)
+          modelComponent.dereference.set(true)
+        }
+      })
     } else {
       EditorControlFunctions.createObjectFromSceneElement(
         [{ name: ModelComponent.jsonID, props: { src: url } }, ...extraComponentJson],

packages/engine/src/gltf/AuthoringHookState.tsx

@@ -0,0 +1,74 @@
+/*
+CPAL-1.0 License
+
+The contents of this file are subject to the Common Public Attribution License
+Version 1.0. (the "License"); you may not use this file except in compliance
+with the License. You may obtain a copy of the License at
+https://github.com/EtherealEngine/etherealengine/blob/dev/LICENSE.
+The License is based on the Mozilla Public License Version 1.1, but Sections 14
+and 15 have been added to cover use of software over a computer network and 
+provide for limited attribution for the Original Developer. In addition, 
+Exhibit A has been modified to be consistent with Exhibit B.
+
+Software distributed under the License is distributed on an "AS IS" basis,
+WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the
+specific language governing rights and limitations under the License.
+
+The Original Code is Ethereal Engine.
+
+The Original Developer is the Initial Developer. The Initial Developer of the
+Original Code is the Ethereal Engine team.
+
+All portions of the code written by the Ethereal Engine team are Copyright © 2021-2023 
+Ethereal Engine. All Rights Reserved.
+*/
+
+import { EntityUUID, UUIDComponent } from '@etherealengine/ecs'
+import { NO_PROXY, defineState, getMutableState, useState } from '@etherealengine/hyperflux'
+import React, { useEffect } from 'react'
+import { generateUUID } from 'three/src/math/MathUtils'
+import { GLTFDocumentState } from './GLTFDocumentState'
+
+export type AuthoringHook = {
+  entityUUID: EntityUUID
+  sceneID: string
+  callback: (entityUUID: EntityUUID) => void
+}
+
+type AuthoringHookJob = AuthoringHook & { hookID: string }
+
+export function addAuthoringHook(hook: AuthoringHook): string {
+  const hookID = generateUUID()
+  getMutableState(AuthoringHookState).merge([{ ...hook, hookID }])
+  return hookID
+}
+
+export const AuthoringHookState = defineState({
+  name: 'AuthoringHookState',
+  initial: [] as AuthoringHookJob[],
+  reactor: () => {
+    const hooks = useState(getMutableState(AuthoringHookState))
+    return (
+      <>
+        {hooks.get(NO_PROXY).map((hook) => (
+          <HookReactor key={hook.hookID} {...hook} />
+        ))}
+      </>
+    )
+  }
+})
+
+const HookReactor = (props: AuthoringHookJob) => {
+  const { entityUUID, sceneID, callback } = props
+  const authoringHooks = getMutableState(AuthoringHookState)
+  const gltfDocument = useState(getMutableState(GLTFDocumentState))[sceneID]
+  if (!gltfDocument.value) return null
+  useEffect(() => {
+    const entity = gltfDocument.value.nodes!.find((node) => node.extensions![UUIDComponent.jsonID] === entityUUID)
+    if (entity) {
+      callback(entityUUID)
+      authoringHooks.set(authoringHooks.value.filter((hook) => hook.hookID !== props.hookID))
+    }
+  }, [gltfDocument])
+  return null
+}