[C#] Using the same input option to start and stop movement

If you're okay with trying another method all together, here's what I did to setup an FPS style controller script:

1. In Unity5 import the asset package Standard Assets/Characters.

2. Create an instance of RigidBodyFPSController.prefab from that package.

3. Remove it's child object, "MainCamera"

4. Import the Google cardboard unitypackage.

5. Replace the "MainCamera" you removed in step #3 with CardboardMain.prefab

6. Update or modify a copy of RigidbodyFirstPersonController.cs GetInput() method.

GetInput() with Google Cardboard forward movement fallback:

 private Vector2 GetInput()
 {
     Vector2 input = new Vector2
     {
         x = Input.GetAxis("Horizontal"),
         y = Input.GetAxis("Vertical")
     };
 
     // If GetAxis are empty, try alternate input methods.
     if (Math.Abs(input.x) + Math.Abs(input.y) < 2 * float.Epsilon)
     {
         if (IsMoving) //IsMoving is the flag for forward movement. This is the bool that would be toggled by a click of the Google cardboard magnet
         {
             input = new Vector2(0, 1); // go straight forward by setting positive Vertical
         }
     }
     movementSettings.UpdateDesiredTargetSpeed(input);
     return input;
 }

I wanted to hold down to move forward. But Google's SDK only support's detecting a magnet "click". If you also want to hold down the magnet to move forward, I recommend using Cardboard Controls+ from the Unity3D Asset Store.

I came across a similar script in Daniel Borowski's tutorial: http://danielborowski.com/posts/create-a-virtual-reality-game-for-google-cardboard/

This included a public variable: checkAutoWalk

So I just added a trigger function to toggle it:

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 
 // Require a character controller to be attached to the same game object
 [RequireComponent(typeof(CharacterMotor))]
 [AddComponentMenu("Character/FPS Input Controller Horiz")]
 
 public class FPSInputControllerC : MonoBehaviour
 {
     private CharacterMotor motor;
     public bool checkAutoWalk = false;
 
 
     // Use this for initialization
     void Awake()
     {
         motor = GetComponent<CharacterMotor>();
 
     }
     
     // Update is called once per frame
     void Update()
     {
 
         // Get the input vector from keyboard or analog stick
         Vector3 directionVector;
         
         if (!checkAutoWalk) { 
             directionVector = new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));
         } else { 
             directionVector = new Vector3(0, 0, 1);
         }
 
         if (directionVector != Vector3.zero)
         {
             // Get the length of the directon vector and then normalize it
             // Dividing by the length is cheaper than normalizing when we already have the length anyway
             float directionLength = directionVector.magnitude;
             directionVector = directionVector / directionLength;
             
             // Make sure the length is no bigger than 1
             directionLength = Mathf.Min(1.0f, directionLength);
             
             // Make the input vector more sensitive towards the extremes and less sensitive in the middle
             // This makes it easier to control slow speeds when using analog sticks
             directionLength = directionLength * directionLength;
             
             // Multiply the normalized direction vector by the modified length
             directionVector = directionVector * directionLength;
         }
         
         // Apply the direction to the CharacterMotor
         motor.inputMoveDirection = transform.rotation * directionVector;
         motor.inputJump = Input.GetButton("Jump");
     }
 
     void OnEnable(){
         Cardboard.SDK.OnTrigger += TriggerPulled;
     }
     
     void OnDisable(){
         Cardboard.SDK.OnTrigger -= TriggerPulled;
     }
     void TriggerPulled() {
         checkAutoWalk = !checkAutoWalk;
     }
 
 }