PositionViewer/Assets/Scripts/Controllers/CreateFance.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CreateFance : MonoBehaviour
{
    bool creating = false;
    ShowMousePosition pointer;
    public GameObject polePrefab;
    public GameObject fencePrefab;
    GameObject lastPole;

    // Start is called before the first frame update
    void Start()
    {
        pointer = GetComponent<ShowMousePosition>();
    }

    // Update is called once per frame
    void Update()
    {
        getInput();
    }

    void getInput()
    {
        if(Input.GetMouseButtonDown(0))
        {
            startFence();
        }
        else if (creating)
        {
            updateFence();
        }
        if (Input.GetMouseButtonUp(0)) creating = false;
    }

    void startFence()
    {
        creating = true;
        var startPos = pointer.getWorldPoint();
        startPos = pointer.snapPosition(startPos);
        var startPole = Instantiate(polePrefab, startPos, Quaternion.identity);
        startPole.transform.position = new Vector3(startPos.x, startPos.y + 0.3f, startPos.z);
        lastPole = startPole;
    }

    void setFence()
    {
        creating = false;
    }

    void updateFence()
    {
        var current = pointer.getWorldPoint();
        current = pointer.snapPosition(current);
        current = new Vector3(current.x, current.y + 0.3f, current.z);
        if(!current.Equals(lastPole.transform.position))
        {
            CreateFenceSegment(current);
        }
    }

    void CreateFenceSegment(Vector3 current)
    {
        var newPole = Instantiate(polePrefab, current, Quaternion.identity);
        var middle = Vector3.Lerp(newPole.transform.position, lastPole.transform.position, 0.5f);
        var newFence = Instantiate(fencePrefab, middle, Quaternion.identity);
        newFence.transform.LookAt(lastPole.transform);
        lastPole = newPole;
    }
}