Limit where I can Instantiate on mousedown?

Question

My script puts an object at the position of the mouse, regardless of the position.

I'd like to limit where I can place the object to a small area around the player sprite.

Say if mouse X if greater than (X position + a little) of the players X than the object wont Instantiate. I've tried if statements along these lines but haven't been able to get it to work.

Here is the placement script.

 public GameObject seedlings;
 public GameObject player;
 Vector3 mousePOS = Input.mousePosition;

 // Use this for initialization
 void Start(){}
 // Update is called once per frame
 void Update()
 {
     PlantInGround();
 }
 void PlantInGround()
 {
     Vector3 mousePOS = Input.mousePosition;

         if (Input.GetMouseButtonDown(0))
         {
             mousePOS.z = +12;
             mousePOS = Camera.main.ScreenToWorldPoint(mousePOS);
             Instantiate(seedlings, (mousePOS), Quaternion.identity);
             Debug.Log(mousePOS);
         }
 }

Grateful for any help.

Answer 1

This is what ended up working. Leaving it for others. I honestly don't know why the coordinates just lined up. Thanks for the help @Lincon.

public class PlantItem : MonoBehaviour {

public GameObject seedlings;
public GameObject player;
Vector3 mousePOS = Input.mousePosition;

void Update()
{
    if (!Input.GetMouseButtonDown(0))
    {
        PlantInGround();
    }
}

void PlantInGround()
{
    Vector3 mousePOS = Input.mousePosition;

    mousePOS.z = +12;
    mousePOS = Camera.main.ScreenToWorldPoint(mousePOS);
    if (((player.transform.position.y < mousePOS.y + 0.5) && (player.transform.position.y > mousePOS.y - 1.5)) && ((player.transform.position.x < mousePOS.x + 1) && (player.transform.position.x > mousePOS.x - 1)))
    {
        Instantiate(seedlings, mousePOS, Quaternion.identity);

    }
}

}

Answer 2

To check if the your seedling position is near your player's position:

float maxDist = 3F; //radius within the player that the seedling can be instantiated
if ( (mousePOS - player.transform.position).magnitude < maxDist )
{
  //Do Something
}

You could compare the distance squared instead, since magnitude involves a Sqrt() call which is expensive, but given that you are doing this only on a mouse click, it shouldn't really matter much.

Of course, you have to be sure that your player is about 12 units away from the camera's forward viewing direction.. given that you are doing this:

mousePOS.z = +12;
mousePOS = Camera.main.ScreenToWorldPoint(mousePOS);