MultipleModelUtil

Overview

Utility Class for loading models in sequence for Forge Viewer.

This video shows core concepts of this tool: https://youtu.be/nfHZLlWtQ-0?t=16

A reversion of this official blog: Aggregate multi models in sequence in Forge Viewer.

Usage

1. Include libraries

<link rel="stylesheet" href="https://developer.api.autodesk.com/viewingservice/v1/viewers/7.*/style.min.css" type="text/css">
<script src="https://developer.api.autodesk.com/viewingservice/v1/viewers/7.*/viewer3D.js"></script>
<script src="MultipleModelUtil.js"></script>

2. Create instance of the MultipleModelUtil inside the Autodesk.Viewing.Initializer callback, then call MultipleModelUtil#processModels to load all models

Autodesk.Viewing.Initializer( options, function() {

  //get the viewer div
  const viewerDiv = document.getElementById( 'viewer' );

  //initialize the viewer object
  const viewer = new Autodesk.Viewing.Private.GuiViewer3D( viewerDiv );

  //load model one by one in sequence
  const util = new MultipleModelUtil( viewer );
  util.processModels( models );
});

Example

function fetchForgeToken( callback ) {
  fetch( 'https://127.0.0.1/api/forge/oauth/token', {
    method: 'get',
    headers: new Headers({ 'Content-Type': 'application/json' })
  })
  .then( ( response ) => {
  if( response.status === 200 ) {
      return response.json();
  } else {
      return Promise.reject(
        new Error( `Failed to fetch token from server (status: ${response.status}, message: ${response.statusText})` )
      );
  }
  })
  .then( ( data ) => {
    if( !data ) return Promise.reject( new Error( 'Empty token response' ) );

    callback( data.access_token, data.expires_in );
  })
  .catch( ( error ) => console.error( error ) );
}

function launchViewer( models ) {
  if( !models || models.length <= 0 )
    return console.error( 'Empty model input' );

  const options = {
    env: 'AutodeskProduction',
    getAccessToken: fetchForgeToken
    //accessToken: 'eyJhbGciOiJIUzI1NiIs....'
  };

  Autodesk.Viewing.Initializer( options, function() {

    //get the viewer div
    const viewerDiv = document.getElementById( 'viewer' );

    //initialize the viewer object
    const viewer = new Autodesk.Viewing.Private.GuiViewer3D( viewerDiv );

    //load model one by one in sequence
    const util = new MultipleModelUtil( viewer );
    util.processModels( models );
  });
}

const models = [
  { name: '1.nwc', urn: 'urn:dXJuOmFkc2sud2lwcHJvZDpmcy5maWxlOnZmLlNpaHgxOTVuUVJDMHIyWXZUSVRuZFE/dmVyc2lvbj0x' },
  { name: '2.nwc', urn: 'urn:dXJuOmFkc2sud2lwcHJvZDpmcy5maWxlOnZmLldVRHJ4ajZ6UTBPLTRrbWZrZ3ZoLUE/dmVyc2lvbj0x' },
  { name: '3.nwc', urn: 'urn:dXJuOmFkc2sud2lwcHJvZDpmcy5maWxlOnZmLjRyZW5HRTNUU25xNHhYaW5xdWtyaWc/dmVyc2lvbj0x' }
];

launchViewer( models.concat() );

Supported alignments

This utility supports 4 kinds alignments as the below:

• Center to center: the default way of the viewer.

  const util = new MultipleModelUtil( viewer );
  
  util.options = {
    alignment: MultipleModelAlignmentType.CenterToCenter
  };
  util.processModels( models );

• Origin to origin: Apply the globalOffset of the 1st model to others. (This is the default alignment method of this utility)

  const util = new MultipleModelUtil( viewer );
  
  util.options = {
    alignment: MultipleModelAlignmentType.OriginToOrigin
  };
  util.processModels( models );

• By Revit shared coordinates: Set up applyRefpoint: true and make the globalOffset to the refPoint. (AEC model data is required)

  const util = new MultipleModelUtil( viewer );
  
  util.options = {
    alignment: MultipleModelAlignmentType.ShareCoordinates
  };
  util.processModels( models );

• Custom alignment: If the above alignments don't match your need, you can use this option to set up custom alignments.

  const util = new MultipleModelUtil( viewer );
  
  util.options = {
    alignment: MultipleModelAlignmentType.Custom,
    getCustomLoadOptions: (bubble, data) => {
      console.log(bubble, data);
      
      const tx = new THREE.Matrix4();
      tx.setPosition({ x:1, y:100, z:1 }).scale({ x:2, y:2, z:2 });
      return {
        placementTransform: tx
      };
    }
  };
  util.processModels( models );

Note. Forge Viewer supports 3 kinds of Revit link methods as I shared here:

• Origin to origin
• Center to center
• By shared coordinate

License

This sample is licensed under the terms of the MIT License. Please see the LICENSE file for full details.

Written by

Eason Kang @yiskang, Forge Partner Development