I am making a board game in unity 4.3 2d similar to checkers. I have added an empty object to all the points where player can move and added a box collider to each empty object.I attached a click to move script to each player token. Now I want to assign valid moves. e.g. as shown in picture... Players can only move on vertex of each square.Player can only move to adjacent vertex.Thus it can only move from red spot to yellow and cannot move to blue spot.There is another condition which is : if there is the token of another player at the yellow spot then the player cannot move to that spot. Instead it will have to go from red to green spot. How can I find the valid moves of the player by scripting.

I have another problem with click to move. When I click all the objects move to that position.But I only want to move a single token. So what can i add to script to select a specific object and then click to move the specific object.Here is my script for click to move.

var obj:Transform;

private var hitPoint : Vector3;

private var move: boolean = false;

private var startTime:float;

var speed = 1;


function Update ()
{
if(Input.GetKeyDown(KeyCode.Mouse0))
{
var hit : RaycastHit; // no point storing this really
var ray = Camera.main.ScreenPointToRay (Input.mousePosition);
if (Physics.Raycast (ray, hit, 10000))
{
hitPoint = hit.point;
move = true;
startTime = Time.time;
}
}

if(move)
{
obj.position = Vector3.Lerp(obj.position, hitPoint, Time.deltaTime * speed);
if(obj.position == hitPoint)
{
move = false;
}
}
}`