Category: Unity

The [SteamVR] API makes the motion controller touchpad input available.

1 Import the SteamVR Plugin

2 Open the `Assets\SteamVR\InteractionSystem\Samples\Scenes\Interactions_Example.unity` scene

3 Attach `StickManipulation.cs` on the SteamVR `Player`.

using UnityEngine;
using Valve.VR;
using Valve.VR.InteractionSystem;

public class StickManipulation : MonoBehaviour
{
    private float _mMoveSpeed = 2.5f;
    private float _mHorizontalTurnSpeed = 180f;
    private float _mVerticalTurnSpeed = 2.5f;
    private bool _mInverted = false;
    private const float VERTICAL_LIMIT = 60f;

    private void OnGUI()
    {
        Player player = Player.instance;
        if (!player)
        {
            return;
        }

        EVRButtonId touchPad = EVRButtonId.k_EButton_SteamVR_Touchpad;

        if (null != player.leftController)
        {
            var touchPadVector = player.leftController.GetAxis(touchPad);
            GUILayout.Label(string.Format("Left X: {0:F2}, {1:F2}", touchPadVector.x, touchPadVector.y));
        }

        if (null != player.rightController)
        {
            var touchPadVector = player.rightController.GetAxis(touchPad);
            GUILayout.Label(string.Format("Right X: {0:F2}, {1:F2}", touchPadVector.x, touchPadVector.y));
        }
    }

    float GetAngle(float input)
    {
        if (input < 0f)
        {
            return -Mathf.LerpAngle(0, VERTICAL_LIMIT, -input);
        }
        else if (input > 0f)
        {
            return Mathf.LerpAngle(0, VERTICAL_LIMIT, input);
        }
        return 0f;
    }

    // Update is called once per frame
    void Update()
    {
        Player player = Player.instance;
        if (!player)
        {
            return;
        }

        EVRButtonId touchPad = EVRButtonId.k_EButton_SteamVR_Touchpad;

        if (null != player.leftController)
        {
            Quaternion orientation = Camera.main.transform.rotation;
            var touchPadVector = player.leftController.GetAxis(touchPad);
            Vector3 moveDirection = orientation * Vector3.forward * touchPadVector.y + orientation * Vector3.right * touchPadVector.x;
            Vector3 pos = player.transform.position;
            pos.x += moveDirection.x * _mMoveSpeed * Time.deltaTime;
            pos.z += moveDirection.z * _mMoveSpeed * Time.deltaTime;
            player.transform.position = pos;
        }

        if (null != player.rightController)
        {
            Quaternion orientation = player.transform.rotation;
            var touchPadVector = player.rightController.GetAxis(touchPad);

            Vector3 euler = transform.rotation.eulerAngles;
            float angle;
            if (_mInverted)
            {
                angle = GetAngle(touchPadVector.y);
            }
            else
            {
                angle = GetAngle(-touchPadVector.y);
            }
            euler.x = Mathf.LerpAngle(euler.x, angle, _mVerticalTurnSpeed * Time.deltaTime);
            euler.y += touchPadVector.x * _mHorizontalTurnSpeed * Time.deltaTime;
            player.transform.rotation = Quaternion.Euler(euler);
        }
    }
}