我是 Unity 新手，我正在尝试弄清楚如何使用触摸输入在地图/地形上移动相机。摄像机将以 (90,0,0) 的旋转角度俯视地形。地形位于第 8 层。我用键盘移动它没有问题，现在我尝试移动到触摸，如果你想在 iOS 上保持预期的使用情况，那就非常不同了。
我能想到的内置 iOS 应用程序的最佳示例是地图，用户触摸屏幕，只要手指停留在屏幕上，地图上的该点就会停留在手指下方。因此，当用户移动手指时，地图似乎会随着手指移动。我无法找到说明如何以这种方式执行此操作的示例。我见过很多用鼠标移动相机或角色的例子，但它们似乎并不能很好地转化为这种风格。
也发布在Unity3D上的答案：
http://answers.unity3d.com/questions/283159/move-camera-over-terrain-using-touch-input.html
以下应该是您所需要的。请注意，使用透视相机时，很难在手指/光标和地形之间获得 1 对 1 的对应关系。如果您将相机更改为正交，下面的脚本应该为您提供手指/光标位置和地图移动之间的完美地图。从角度来看，您会注意到轻微的偏移。
您也可以通过光线追踪来做到这一点，但我发现这条路线很草率而且不那么直观。
用于测试的相机设置（从检查器中提取值，因此将它们应用到那里）：
using UnityEngine;
using System.Collections;
public class ViewDrag : MonoBehaviour {
Vector3 hit_position = Vector3.zero;
Vector3 current_position = Vector3.zero;
Vector3 camera_position = Vector3.zero;
float z = 0.0f;
// Use this for initialization
void Start () {
}
void Update(){
if(Input.GetMouseButtonDown(0)){
hit_position = Input.mousePosition;
camera_position = transform.position;
}
if(Input.GetMouseButton(0)){
current_position = Input.mousePosition;
LeftMouseDrag();
}
}
void LeftMouseDrag(){
// From the Unity3D docs: "The z position is in world units from the camera." In my case I'm using the y-axis as height
// with my camera facing back down the y-axis. You can ignore this when the camera is orthograhic.
current_position.z = hit_position.z = camera_position.y;
// Get direction of movement. (Note: Don't normalize, the magnitude of change is going to be Vector3.Distance(current_position-hit_position)
// anyways.
Vector3 direction = Camera.main.ScreenToWorldPoint(current_position) - Camera.main.ScreenToWorldPoint(hit_position);
// Invert direction to that terrain appears to move with the mouse.
direction = direction * -1;
Vector3 position = camera_position + direction;
transform.position = position;
}
}
我想出了这个脚本（我已将其附加到相机）：
private Vector2 worldStartPoint;
void Update () {
// only work with one touch
if (Input.touchCount == 1) {
Touch currentTouch = Input.GetTouch(0);
if (currentTouch.phase == TouchPhase.Began) {
this.worldStartPoint = this.getWorldPoint(currentTouch.position);
}
if (currentTouch.phase == TouchPhase.Moved) {
Vector2 worldDelta = this.getWorldPoint(currentTouch.position) - this.worldStartPoint;
Camera.main.transform.Translate(
-worldDelta.x,
-worldDelta.y,
0
);
}
}
}
// convert screen point to world point
private Vector2 getWorldPoint (Vector2 screenPoint) {
RaycastHit hit;
Physics.Raycast(Camera.main.ScreenPointToRay(screenPoint), out hit);
return hit.point;
}
Pavel 的回答对我帮助很大，因此想与社区分享我的解决方案，以防对其他人有帮助。我的场景是一个带有正交相机的 3D 世界。我正在开发一款自上而下风格的即时战略游戏。我希望平移和缩放像 Google 地图一样工作，当您平移和缩放时，鼠标始终停留在地图上的同一位置。该脚本为我实现了这一点，并希望足够强大，可以满足其他人的需求。我没有对其进行大量测试，但我对其进行了评论，供初学者学习。
using UnityEngine;
// I usually attach this to my main camera, but in theory you can attach it to any object in scene, since it uses Camera.main instead of "this".
public class CameraMovement : MonoBehaviour
{
private Vector3 MouseDownPosition;
void Update()
{
// If mouse wheel scrolled vertically, apply zoom...
// TODO: Add pinch to zoom support (touch input)
if (Input.mouseScrollDelta.y != 0)
{
// Save location of mouse prior to zoom
var preZoomPosition = getWorldPoint(Input.mousePosition);
// Apply zoom (might want to multiply Input.mouseScrollDelta.y by some speed factor if you want faster/slower zooming
Camera.main.orthographicSize = Mathf.Clamp(Camera.main.orthographicSize + Input.mouseScrollDelta.y, 5, 80);
// How much did mouse move when we zoomed?
var delta = getWorldPoint(Input.mousePosition) - preZoomPosition;
// Rotate camera to top-down (right angle = 90) before applying adjustment (otherwise we get "slide" in direction of camera angle).
// TODO: If we allow camera to rotate on other axis we probably need to adjust that also. At any rate, you want camera pointing "straight down" for this part to work.
var rot = Camera.main.transform.localEulerAngles;
Camera.main.transform.localEulerAngles = new Vector3(90, rot.y, rot.z);
// Move the camera by the amount mouse moved, so that mouse is back in same position now.
Camera.main.transform.Translate(delta.x, delta.z, 0);
// Restore camera rotation
Camera.main.transform.localEulerAngles = rot;
}
// When mouse is first pressed, just save location of mouse/finger.
if (Input.GetMouseButtonDown(0))
{
MouseDownPosition = getWorldPoint(Input.mousePosition);
}
// While mouse button/finger is down...
if (Input.GetMouseButton(0))
{
// Total distance finger/mouse has moved while button is down
var delta = getWorldPoint(Input.mousePosition) - MouseDownPosition;
// Adjust camera by distance moved, so mouse/finger stays at exact location (in world, since we are using getWorldPoint for everything).
Camera.main.transform.Translate(delta.x, delta.z, 0);
}
}
// This works by casting a ray. For this to work well, this ray should always hit your "ground". Setup ignore layers if you need to ignore other colliders.
// Only tested this with a simple box collider as ground (just one flat ground).
private Vector3 getWorldPoint(Vector2 screenPoint)
{
RaycastHit hit;
Physics.Raycast(Camera.main.ScreenPointToRay(screenPoint), out hit);
return hit.point;
}
}
根据 Pavel 的回答，我简化了脚本，并删除了用多于一根手指触摸并释放第二根手指时不可爱的“跳跃”：
private bool moreThenOneTouch = false;
private Vector3 worldStartPoint;
void Update() {
Touch currentTouch;
// only work with one touch
if (Input.touchCount == 1 && !moreThenOneTouch) {
currentTouch = Input.GetTouch(0);
if (currentTouch.phase == TouchPhase.Began) {
this.worldStartPoint = Camera.main.ScreenToWorldPoint(currentTouch.position);
}
if (currentTouch.phase == TouchPhase.Moved) {
Vector3 worldDelta = Camera.main.ScreenToWorldPoint(currentTouch.position) - this.worldStartPoint;
Camera.main.transform.Translate(
-worldDelta.x,
-worldDelta.y,
0
);
}
}
if (Input.touchCount > 1) {
moreThenOneTouch = true;
} else {
moreThenOneTouch = false;
if(Input.touchCount == 1)
this.worldStartPoint = Camera.main.ScreenToWorldPoint(Input.GetTouch(0).position);
}
}
我已经使用了你们写的第一个代码，它起作用了，但是，我希望地形或地图在我移开手指时不会立即停止，我希望它滑动一点然后停止，比如一两秒，所以如果我用手指滑动地形，它会留在我的手指下，但如果我滑动并放开，地形会继续滑动一秒钟？这可能吗
using UnityEngine;
// I usually attach this to my main camera, but in theory you can attach it to any object in scene, since it uses Camera.main instead of "this".
public class CameraMovement : MonoBehaviour
{
private Vector3 MouseDownPosition;
void Update()
{
// If mouse wheel scrolled vertically, apply zoom...
// TODO: Add pinch to zoom support (touch input)
if (Input.mouseScrollDelta.y != 0)
{
// Save location of mouse prior to zoom
var preZoomPosition = getWorldPoint(Input.mousePosition);
// Apply zoom (might want to multiply Input.mouseScrollDelta.y by some speed factor if you want faster/slower zooming
Camera.main.orthographicSize = Mathf.Clamp(Camera.main.orthographicSize + Input.mouseScrollDelta.y, 5, 80);
// How much did mouse move when we zoomed?
var delta = getWorldPoint(Input.mousePosition) - preZoomPosition;
// Rotate camera to top-down (right angle = 90) before applying adjustment (otherwise we get "slide" in direction of camera angle).
// TODO: If we allow camera to rotate on other axis we probably need to adjust that also. At any rate, you want camera pointing "straight down" for this part to work.
var rot = Camera.main.transform.localEulerAngles;
Camera.main.transform.localEulerAngles = new Vector3(90, rot.y, rot.z);
// Move the camera by the amount mouse moved, so that mouse is back in same position now.
Camera.main.transform.Translate(delta.x, delta.z, 0);
// Restore camera rotation
Camera.main.transform.localEulerAngles = rot;
}
// When mouse is first pressed, just save location of mouse/finger.
if (Input.GetMouseButtonDown(0))
{
MouseDownPosition = getWorldPoint(Input.mousePosition);
}
// While mouse button/finger is down...
if (Input.GetMouseButton(0))
{
// Total distance finger/mouse has moved while button is down
var delta = getWorldPoint(Input.mousePosition) - MouseDownPosition;
// Adjust camera by distance moved, so mouse/finger stays at exact location (in world, since we are using getWorldPoint for everything).
Camera.main.transform.Translate(delta.x, delta.z, 0);
}
}
// This works by casting a ray. For this to work well, this ray should always hit your "ground". Setup ignore layers if you need to ignore other colliders.
// Only tested this with a simple box collider as ground (just one flat ground).
private Vector3 getWorldPoint(Vector2 screenPoint)
{
RaycastHit hit;
Physics.Raycast(Camera.main.ScreenPointToRay(screenPoint), out hit);
return hit.point;
}
}