Prerequisites

This project assumes you are familiar with the basic functionality of Unity. You should also review the following before moving on:

• Getting Started Kit - Advanced Lessons - Smart Phidget Events
• Getting Started Kit - Advanced Lessons - Data Interval

Setup

Make sure you have the following parts before getting started.

Attach your Thumbstick Phidget to your VINT Hub as shown:

Configure Unity

In order to use Phidgets with Unity, you have to configure your project. Follow the instructions below.

Create Environment

Now that your project is configured, you can create your environment.

Write Code (C#)

Copy the code below into your BallScript file.

  
using UnityEngine;
using Phidget22;

public class BallScript : MonoBehaviour
{

    private Rigidbody rb;
    DigitalInput button;
    VoltageRatioInput vertical;
    VoltageRatioInput horizontal;
    bool shouldJump = false;

    //Button Event 
    void Button_StateChange(object sender, Phidget22.Events.DigitalInputStateChangeEventArgs e)
    {
        shouldJump = e.State;
    }

    // Start is called before the first frame update
    void Start()
    {
        //Connect Rigidbody
        rb = GetComponent <Rigidbody>();

        //Create
        button = new DigitalInput();
        vertical = new VoltageRatioInput();
        horizontal = new VoltageRatioInput();

        //Address | There are two VoltageRatioInputs available. Setting the channel differentiates between the two
        vertical.Channel = 0;
        horizontal.Channel = 1;

        //Subscribe to Events 
        button.StateChange += Button_StateChange;

        //Open
        button.Open(1000);
        vertical.Open(1000);
        horizontal.Open(1000);

        //Set data interval to minimum | This will increase the data rate from the sensor and allow for smoother movement
        vertical.DataInterval = vertical.MinDataInterval;
        horizontal.DataInterval = horizontal.MinDataInterval;
    }

    // Update is called once per frame
    void Update()
    {
        //Use your Phidgets
        float x = (float)horizontal.VoltageRatio;
        float z = (float)vertical.VoltageRatio;        
        float y = shouldJump ? 250.0f : 0.0f;
        shouldJump = false; //reset
        Vector3 movement = new Vector3(x, y, z);
        rb.AddForce(movement);        
    }

    //Required for Unity and Phidgets
    private void OnApplicationQuit()
    {
        button.Close();
        button.Dispose();
        vertical.Close();
        vertical.Dispose();
        horizontal.Close();
        vertical.Dispose();
    }
}
  

Run Your Program

When you run your code, you will see the ball move based on the position of the thumbstick. Press the button to make the ball jump.

Code Review

When using the Thumbstick Phidget, you have three objects to create an use:

• Horizontal Axis
• Vertical Axis
• Push Button

When using the horizontal and vertical axes, it's important to set the data interval to the minimum as shown in the code above. This will ensure your sensor is as responsive as possible.

When using the push button, it's a good idea to use events. Events will allow you to easily determine when the button has been pushed or released. Polling can also be used, however, extra code will be required.

Practice

1. Try adding a multiplier to the horizontal/vertical axes. This will make your ball more sensitive to movement of the thumbstick.

  
    // Update is called once per frame
    void Update()
    {
        //Use your Phidgets
        float multiplier = 3.0f;
        float x = (float)horizontal.VoltageRatio;        
        float z = (float)vertical.VoltageRatio;  
        x *= multiplier;              
        z *= multiplier;
        float y = shouldJump ? 250.0f : 0.0f;
        shouldJump = false; //reset
        Vector3 movement = new Vector3(x, y, z);
        rb.AddForce(movement);        
    }
  

2. Instead of adding a force to your sphere based on the thumbstick, try mapping the position of your thumbstick to the sphere directly.

  
    // Update is called once per frame
    void Update()
    {
        //Use your Phidgets
        float x = (float)horizontal.VoltageRatio * 4.0f;
        float z = (float)vertical.VoltageRatio * 4.0f;         
        rb.position = new Vector3(x, rb.position.y, z); 
    }