A common task is moving one object towards another position in Unity. Assuming you want constant, linear speed, Vector.MoveTowards is a great solution. You can also do lerping covered in this article here.

I experimented with this in an earlier prototype of Puzzledorf to make pieces slide across the board, although in the end I decided snappy movements worked better for a grid-like puzzler – it helps the game to keep up with your brain so you can try lots of solutions quickly. So if you use Vector.MoveTowards, think about the speed of it and trial it.

Move Towards

The psuedocode is:

Object to move = MoveTowards( currentPosition, endPosition, speed);

Example code:

piece.transform.position = Vector3.MoveTowards(piece.transform.position, end, speed * Time.deltaTime);

It says, move the object from it’s current position towards the end position at the following speed.

current position  is not the objects starting position, but its position each frame, because each frame it checks the current position and moves it closer towards the end position.

endPosition is simply where want your object to finish moving.

Speed is the speed to move. We multiply speed by deltaTime because, if speed was 1, we would be saying, “We want this object to take one second to move”. Multiplying the speed by delta time makes sure that movement is divided up evenly across the update frames. Increase the speed and the object will move faster.

Example code:

public GameObject block;

void Update ()
 { 
    if (Input.GetKeyDown(KeyCode.Space))
    { 
        StartCoroutine(MovePieceTowards(block, block.transform.position + new Vector3(10, 0, 0), 10)); 
    }
 }

 IEnumerator MovePieceTowards(GameObject piece, Vector3 end, float speed)
 {
    while (piece.transform.position != end)
    {
        piece.transform.position = Vector3.MoveTowards(piece.transform.position, end, speed * Time.deltaTime);
        yield return null;
    }
 }

We have a public game object called block. Pass any object you like in the inspector.

On Update, we start a Coroutine when we press the Space key. We pass the block game object in, we set it’s end destination, and we set the speed. Currently it will move 10  units to the right.

The co-routine keeps running until the object has finished moving. We return null because co-routines have to return a value. Try it out. If you are still a bit unsure about MoveTowards, try looking at the Unity documentation here.