如何在鼠标路径上生成对象？ 统一 3D

Question

这就是我想要实现的目标：

移动鼠标（鼠标按钮按下）时，我想保存整个鼠标移动，我的意思是从开始（单击按钮）点到结束（释放按钮）点。 释放按钮后，我想在整个保存的鼠标路径上生成一些对象（如图所示），并且每两个生成的对象之间的空间应该相同。

• 世界是 3D 的，但对象应该只在 X 和 Y 轴上生成，Z 轴将是固定的。

我怎样才能在代码中做到这一点？ 我已经开始了：

void Update()
{
    if (Input.GetMouseButtonDown(0))
    {
        screenPoint = Camera.main.WorldToScreenPoint(transform.position);
    }

    if (Input.GetMouseButton(0) && !Input.GetMouseButtonDown(0))
    {
        Vector3 curScreenPoint = new Vector3(Input.mousePosition.x, Input.mousePosition.y, transform.position.z);

        Vector3 curPosition = new Vector3(-Camera.main.ScreenToWorldPoint(curScreenPoint).x, -Camera.main.ScreenToWorldPoint(curScreenPoint).y, transform.position.z);

        if ((Input.GetAxis("Mouse X") != 0) || (Input.GetAxis("Mouse Y") != 0));
        {
            GameObject TheBall = Instantiate(Ball, curPosition, Quaternion.identity);
            TheBall.transform.SetParent(transform, false);
        }         
    }

Answer 1

就像我说的，你首先可能会得到每个点之间的平均空间。 之后，您将始终从之前的位置创建新点。 你可以这样做：

public GameObject prefab;
List<Vector2> points = new List<Vector2>();

void Update() {
    // You add the points in update to the List
    if(Input.GetMouseButtonUp(0)) {
        float totalDistance = 0;
        for(int i = 0; i < points.Count-1; i++) {
            totalDistance += Vector2.Distance(points[i], points[i+1]);
        }
        float averageDistance = totalDistance / (points.Count-1);

        // Spawning first Point
        Vector2 lastPoint = points[0];
        Instantiate(
            prefab, 
            new Vector3(lastPoint.x, z, lastPoint.y), 
            Quaternion.identity
        );

        // Spawning other Points
        for(int i = 0; i < points.Count - 1; i++) {
            Vector2 spawnPos = lastPoint + ((points[i+1] - lastPoint).normalized * averageDistance)
            lastPoint = spawnPos; //Save the new point because you want create the next one from this one
            int z = 0; // The z you need
            Instantiate(
                prefab, 
                new Vector3(spawnPos.x, z, spawnPos.y), 
                Quaternion.identity
            );
        }
    }
}

编辑：为您创建了代码。 您的启动代码也有一些问题，但这在这里是有效的。

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

public class SpawnCircles : MonoBehaviour {
    public GameObject prefab;
    public float Y;

    private Camera cam;
    private List<Vector2> points = new List<Vector2>();

    void Update() {
        if(Input.GetMouseButton(0)) {
            cam = Camera.main;
            Vector2 mousePos = new Vector2();
            mousePos.x = Input.mousePosition.x;
            mousePos.y = cam.pixelHeight - Input.mousePosition.y;
            Vector3 point = cam.ScreenToWorldPoint(new Vector3(mousePos.x, mousePos.y, 10));
            points.Add(new Vector2(point.x, point.z * -1));
        }
        if(Input.GetMouseButtonUp(0)) {
            float totalDistance = 0;
            for(int i = 0; i < points.Count - 1; i++) {
                totalDistance += Vector2.Distance(points[i], points[i + 1]);
            }
            float averageDistance = totalDistance / (points.Count - 1);

            // Spawning first Point
            Vector2 lastPoint = points[0];
            Instantiate(
                prefab,
                new Vector3(lastPoint.x, Y, lastPoint.y),
                Quaternion.identity
            );
            // Spawning other Points
            for(int i = 0; i < points.Count - 1; i++) {
                Vector2 spawnPos = lastPoint + ((points[i + 1] - lastPoint).normalized * averageDistance);

                lastPoint = spawnPos; //Save the new point because you want create the next one from this one
                Instantiate(
                    prefab,
                    new Vector3(spawnPos.x, Y, spawnPos.y),
                    Quaternion.identity
                );
            }
            // Resetting List
            points = new List<Vector2>();
        }
    }
}