Untitled

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
public class ObjectScalerWithScreenSize : MonoBehaviour
{
    public Vector2 actualObjectSize;
    public float SIZE_ON_SCREEN;
    public Text sizeText;

    public float screenHeight;
    public float screenWidth;
    void Start()
    {
        float frustumHeight = (Screen.height / Screen.dpi) * 2.54f;
        frustumHeight /= 100f;

        Debug.Log(Screen.dpi);
        Debug.Log(Screen.width + " " + Screen.height);
        Debug.Log((Screen.width / Screen.dpi) * 2.54f);
        Debug.Log((Screen.height / Screen.dpi) * 2.54f);

        var distance = frustumHeight * 0.5f / Mathf.Tan(Camera.main.fieldOfView * 0.5f * Mathf.Deg2Rad);

        screenHeight = (Screen.height / Screen.dpi) * 2.54f;
        screenHeight /= 100;
        screenWidth = (Screen.width / Screen.dpi) * 2.54f;
        screenWidth /= 100;
    }

    private void Update()
    {
        // float height = Camera.main.orthographicSize * 2.0f;
        // float width = height * Screen.height / Screen.width;
        // gameObject.transform.localScale = Vector3.one * width / SIZE_ON_SCREEN;

        float screenCenterX = (screenWidth / 2);
        float pointLeft = screenCenterX - (actualObjectSize.x / 2);
        float pointRight = screenCenterX + (actualObjectSize.x / 2);

        Debug.Log("Left " + pointLeft + " Right " + pointRight);
        float normalizedLeft = Normalize(pointLeft, 0, screenWidth);
        float normalizedRight = Normalize(pointRight, 0, screenWidth);
        Debug.Log("Left Normalized " + normalizedLeft + " Right Normalized " + normalizedRight);

        Vector3 expectedLeftEndPoint = Camera.main.ViewportToWorldPoint(new Vector3(normalizedLeft, 0.5f, Camera.main.transform.position.z));
        Vector3 actualLeftEndPoint = transform.position - (Vector3.left * (transform.localScale.x / 2));

        float newScale = (expectedLeftEndPoint.x * transform.localScale.x) / actualLeftEndPoint.x;

        transform.localScale = Vector3.one * newScale;
    }

    public void IncreaseSize()
    {
        // SIZE_ON_SCREEN += 0.1f;

        actualObjectSize += Vector2.one * 0.01f;
        sizeText.text = gameObject.transform.localScale.x.ToString() + " : " + actualObjectSize.x;
    }
    public void DecreaseSize()
    {
        // SIZE_ON_SCREEN -= 0.1f;

        actualObjectSize -= Vector2.one * 0.01f;
        sizeText.text = gameObject.transform.localScale.x.ToString() + " : " + actualObjectSize.x;
    }

    public float Remap(float unscaledNum, float minAllowed, float maxAllowed, float min, float max)
    {
        return (maxAllowed - minAllowed) * (unscaledNum - min) / (max - min) + minAllowed;
    }

    public float Normalize(float value, float minimum, float maximum)
    {
        return (value - minimum) / (maximum - minimum);
    }
}