# Building a basic application

Table of Contents

- Project Layout
- Hello Web Viewer
- Custom operator basics
- Advanced operator concepts
- Interacting with the Model Tree
- Color and transparency
- Geometry and Texture Creation
- Model Loading and Aggregation
- Connection to the HOOPS Server

This tutorial will walk you through the fundamentals of writing a web application with HOOPS Communicator (HC). After completion of this tutorial, you should have enough understanding of the technology to start integrating HC into your application.

The prerequisite for this tutorial is a basic understanding of JavaScript (JS) development. No advanced CAD expertise or web development experience is required. All JS code examples are client-side and require no server backend except for the last section, which covers the HOOPS Server and streaming.

### Web Viewer Preview

Double click the Web Viewer canvas to reset the camera position!

#### Model Structure...

Not Ready

#### CameraCallback

    {
            "position": {
                    "x": 0,
                    "y": 0,
                    "z": 0
            },
            "target": {
                    "x": 0,
                    "y": 0,
                    "z": 0
            },
            "up": {
                    "x": 0,
                    "y": 0,
                    "z": 0
            },
            "width": 0,
            "height": 0,
            "projection": 0,
            "nearLimit": 0.0,
            "className": ""
    }