Finding distance with a line

Unity Engine
1

So I have made it where it finds the distance between the two points of the line, but is there any way that I could make it if you draw a line going down then it is negative, right now it is always positive.

public class LineDrawer : MonoBehaviour
{
    private LineRenderer lineRend;
    private Vector2 mousePos;
    private Vector2 startMousePos;

    [SerializeField]
    private Text distanceText;

    private float distance;

    void Start()
    {
        lineRend=GetComponent<LineRenderer>();
        lineRend.positionCount=2;
    }
    void Update()
    {
        if(Input.GetMouseButtonDown(0))
        {
            startMousePos=Camera.main.ScreenToWorldPoint(Input.mousePosition);
        }

        if (Input.GetMouseButton(0)){
            mousePos=Camera.main.ScreenToWorldPoint(Input.mousePosition);
            lineRend.SetPosition(0,new Vector3(startMousePos.x, startMousePos.y,0f));
            lineRend.SetPosition(1, new Vector3(mousePos.x, mousePos.y,0f));
            distance =(mousePos-startMousePos).magnitude;
            distanceText.text=distance.ToString("F2") + " meters";
        }
        if (Input.GetMouseButtonUp(0)){
            lineRend.SetPosition(0,new Vector3(0, 0,0f));
            lineRend.SetPosition(1, new Vector3(0, 0,0f));
        }
    }
       
   
}
2

Distances are always positive. I don’t understand your question.

How to report your problem productively in the Unity3D forums:

http://plbm.com/?p=220

Beyond that, to help you gain more insight into what the above code is doing, I recommend liberally sprinkling Debug.Log() statements through your code to display information in realtime.

Doing this should help you answer these types of questions:

  • is this code even running? which parts are running? how often does it run? what order does it run in?
  • what are the values of the variables involved? Are they initialized? Are the values reasonable?

Knowing this information will help you reason about the behavior you are seeing.

You can also put in Debug.Break() to pause the Editor when certain interesting pieces of code run, and then study the scene

You could also just display various important quantities in UI Text elements to watch them change as you play the game.

If you are running a mobile device you can also view the console output. Google for how on your particular mobile target.

Here’s an example of putting in a laser-focused Debug.Log() and how that can save you a TON of time wallowing around speculating what might be going wrong:

https://discussions.unity.com/t/839300/3