Slow down camera movement

Unity Engine
1

With this code I can move the camera in my Android game with one finger.

function Update () 
{
	if (Input.touchCount == 1  Input.GetTouch(0).phase == TouchPhase.Moved)
	{
		if (Input.GetTouch(0).deltaPosition.x < 0)
		{
			this.transform.position.x -= -Input.GetTouch(0).deltaPosition.x * dragSpeed;
		}
		
		if (Input.GetTouch(0).deltaPosition.x > 0)
		{
			this.transform.position.x -= -Input.GetTouch(0).deltaPosition.x * dragSpeed;
		}
	}	
}

When I release my finger, it stops moving immediately.
But what I would like to have is that the camera is slowing down after releasing my finger. How can I do that?

2

I think I need at least the speed of the touch:

speedTouch = Input.GetTouch(0).deltaPosition.x;

But how can I slow down this speed to zero? Something with Lerp?

3

Could always have an else statement that says if there is no touchCount, check the speed is not 0, then gradually reduces the speed (possibly with a lerp).

4

Hi,I have a idea that using inertia.

Look at this code:

Vector3 curInertia = Vector3.zero;

void Update(){
    if(Input.GetKey(KeyCode.W)) SetMove(Vector3.forward);
    if(Input.GetKey(KeyCode.S)) SetMove(Vector3.back);
    if(Input.GetKey(KeyCode.A)) SetMove(Vector3.left);
    if(Input.GetKey(KeyCode.D)) SetMove(Vector3.right);
}

void SetMove(Vector3 dir){
	curInertia = dir;
}

IEnumerator Move(){
	thisT.hasChanged = true;
	while (true) {
		thisT.Translate (curInertia * mMoveSpeed * Time.deltaTime, Space.World);

		if(thisT.hasChanged){
			curInertia *= moveInertia*Time.deltaTime;
			thisT.hasChanged = false;
		}

		yield return null;
	}
}

A simple example that show you how to make your movement have a smooth inertia.
Best effect is set moveInertia to 55.
But this algorithm have a mistake that if moveInertia*Time.deltaTime > 1,then your camera will never stop.
Solve this is easy,just lock inertia in -1 ~ 1.
But if you do this ,inertia will never greater than some any value.

Until now,I don’t have a prefect solution

And I will tell you if I got it !!

5

Thanks for reply.
This will help me!

6

Hi Herbie,
I am not shure but when you start a timer like this:

// set dragspeed_timer in Start function to a value you want.
dragspeed_timer -= Time.deltaTime;
if (dragspeed_timer < 0) DoSomething;

dragSpeed = dragspeed_timer → So the variable dragSpeed should go to cero

7

I will try that.
Thanks!

8

Hi,
You let me know that.
Just make “curInertia” to an float,and -= Time.deltaTime*moveInertia every game loop.
And move by *curInertia.
That’s great!!
Thanks you

9

Awful but could be altered to be nice? (it will probably need alot of tweaking as i just quickly wrote this on my phone… Like making the speed dynamic each update instead of at load etc)

    var countDown : float;
    var count : float;
    var dir : String;

    function Start ()
    {
        count = dragSpeed;
        countDown = dragSpeed / 4;
        dir = "n";
    {

    function Update ()
    {
        if (Input.touchCount == 1  Input.GetTouch(0).phase == TouchPhase.Moved)
        {
            count = dragSpeed;
            if (Input.GetTouch(0).deltaPosition.x < 0)
            {
                this.transform.position.x += Input.GetTouch(0).deltaPosition.x * count;
                dir = "r";
            }
           
            if (Input.GetTouch(0).deltaPosition.x > 0)
            {
                this.transform.position.x -= Input.GetTouch(0).deltaPosition.x * count;
                dir = "l";
            }
        } 
        else if (Input.touchCount == 0)
        {
            if (count > 0)
            {
                if (dir == "r")
                {
                    this.transform.position.x += Input.GetTouch(0).deltaPosition.x * count * Time.deltaTime;
                }
           
                if (dir == "l")
                {
                    this.transform.position.x -= Input.GetTouch(0).deltaPosition.x * count * Time.deltaTime;
                }
                count -= countDown * Time.deltaTime;
            }
            else
            {
                count = dragSpeed;
                dir = "n";
            }
        }
        else
        {
            dir = "n";
        }
    }
10 
class Movement : MonoBehaviour
{
  float dragX = 0;
  float mass = 0.2f;
  bool dragging = false;
  float prevX = 0;


void OnEnable()
{
   StartCoroutine(Inertia());
   StartCoroutine(Input());
}

  IEnumerator Inertia()
 {
   while(enabled)
  {

    if(!dragging)
    dragX = Mathf.moveTowards(dragX,0,mass * Time.deltaTIme);


    yield return null;
   }

  yield return null;
 }
  IEnumerator  Input()
  {

    while(enabled)
     {
       
        
        dragX = Input.GetTouch(0).deltaPosition.x * dragSpeed;

         dragging = (prevX != dragX);
         prevX = dragX;
        yield return null;
     }

   yield return null;
  }
}

Untested, but a good start to what you want.

11

Yeah I got while(enable) is good than while(true).

:slight_smile: