@polygon-streaming/web-player-babylonjs

Polygon Streaming Web Player for Babylon.js

Usage

Install the package with:

npm install -S @polygon-streaming/web-player-babylonjs

You will also need to install Babylon.js:

npm install -S @babylonjs/core @babylonjs/loaders

You will need to generate a XRG file from your 3D model which you can do in the console.

Import Babylon.js, glTF loader and the StreamController:

import * as BABYLON from '@babylonjs/core/Legacy/legacy';
import '@babylonjs/loaders/glTF';
import { StreamController } from '@polygon-streaming/web-player-babylonjs';

Next you will need to setup Babylon.js:

const canvas = document.getElementById('application');
const engine = new BABYLON.Engine(canvas, true);
const scene = new BABYLON.Scene(engine);
const cameraTarget = new BABYLON.Vector3(0, 2, 0);
const camera = new BABYLON.ArcRotateCamera('Camera', toRadians(90), toRadians(80), 10, cameraTarget, scene);
camera.attachControl(canvas, true);

Instanciate the stream controller:

const streamController = new StreamController(camera, engine, scene, cameraTarget, {
  cameraType: 'nonPlayer',
  triangleBudget: 3000000,
  mobileTriangleBudget: 1000000,
  closeUpDistance: 0.2,
  minimumDistance: 0.01,
  distanceFactor: 1.1,
  distanceType: 'boundingBoxCenter',
  maximumQuality: 15000,
  closeUpDistanceFactor: 5
});

Add a streaming model, passing it a model URL and a TransformNode to act as a model parent. You can get the model URL by going to the models section of the console and clicking on the three dots next to your model and selecting "Copy asset ID"

const modelParent = new BABYLON.TransformNode('Model parent', scene);
modelParent.position.set(0, 1, 0);

streamController.addModel('<Model URL>', modelParent, {
  qualityPriority: 1,
  initialTrianglePercent: 0.1,
  castShadows: true,
  receiveShadows: true,
  castShadowsLightmap: true,
  forceDoubleSided: false,
  useAlpha: true,
  environmentMap: null,
  hashCode: ''
});

Call the stream controller's update method in the render loop:

engine.runRenderLoop(function () {
  scene.render();
  streamController.update();
});

Stream Controller Parameters

• camera (Required): The camera used in the scene.
• engine (Required): The engine used in the scene.
• scene (Required): The scene object.
• cameraTarget (Required): The camera target which is a Vector3.
• options (Optional): All options are optional. The options are:
  • cameraType: 'nonPlayer' | 'player', default: 'nonPlayer'
    • nonPlayer: A camera that is not attached to a player e.g. a camera that orbits an object.
    • player: A camera that is attached to a player.
  • triangleBudget: number, default: 3000000. The maximum amount of triangles that you want to be in the scene at any single point.
  • mobileTriangleBudget: number, default: 1000000. The triangle budget used on a mobile device. If it is set to 0 it will use the non-mobile triangle budget.
  • minimumDistance: number, default: 0.01. The smallest possible distance to the camera.
  • distanceFactor: number, default: 1.1. Preference for nearby objects over objects further away. Values above one mean a preference for nearby objects. Values below one mean a preference for objects further away. One is neutral.
  • distanceType: 'boundingBoxCenter' | 'boundingBox', default: 'boundingBoxCenter'
    • boundingBoxCenter: Uses the center of the bounding box to caluclate the distance to the node.
    • boundingBox: Uses the bounding box corners and face centers to calulcate the distance to the node.
  • maximumQuality: number, default: 15000. Stops improving geometry that exceeds the maximum quality. This can be used to stop far away objects from showing more detail which can be wasteful. Setting it to 0 means there is no maximum quality.
  • closeUpDistance: number, default: 3. The distance where it starts using close-up distance factor. Set it to 0 to not use close-up distance factor.
  • closeUpDistanceFactor: number, default: 5. The distance factor used when close-up to an object. Should be higher than the standard distance factor.
  • ammoInstance: object, default: null. The Ammo.js instance. Required if you want to make use of the embedded collider.

Streaming Model Parameters

• URL (Required): URL of the XRG model. If it doesn't end with .xrg it will append model.xrg to the URL.
• model parent (Required): The scene object that the streaming model will be attached to.
• options (Optional): All options are optional. The options are:
  • qualityPriority: number, default: 1. How much to prioritize the quality of this model relative to the quality of other models in the scene. This parameter does nothing if this is the only model in the scene.
  • initialTrianglePercent: number, default: 0.1. Percentage of triangle budget to initialize the model with.
  • castShadows: boolean, default: true. Whether the model should cast shadows.
  • receiveShadows: boolean, default: true. Whether the model should receive shadows.
  • castShadowsLightmap: boolean, default: true. Whether the model casts shadows when rendering lightmaps.
  • forceDoubleSided: boolean, default: false. Render the model double sided regardless of the setting in the model file.
  • environmentMap: CubeTexture, default: null. A cube map environment texture.
  • hashCode: string, default: ''. Hash code to validate streaming model.