使用Unity 3D中的触摸输入在地形上移动相机

Question

我是Unity的新手，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。相机将俯视地形，旋转（90,0,0）。地形位于第8层。我使用键盘移动它没有任何问题，现在我正在尝试移动触摸，如果你想在iOS上保持预期用途，那就非常不同了。

我在内置iOS应用程序中可以想到的最好的例子是用户触摸屏幕的地图，只要手指停留在屏幕上，地图上的那个点就会留在手指下。因此，当用户移动他们的手指时，地图似乎随着手指移动。我无法找到显示如何以这种方式执行此操作的示例。我已经看过可能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答案：

http://answers.unity3d.com/questions/283159/move-camera-over-terrain-using-touch-input.html

Answer 1

以下应该是您需要的。请注意，使用“透视”相机时，在手指/光标与地形之间获得1对1的对应关系非常棘手。如果您将相机更改为拼写，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。有了“透视”，你会注意到一点偏移。

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邋and而且不那么直观。

用于测试的相机设置（从检查器中提取值，然后将其应用于那里）：

1. 职位：0,20,0
2. 方向：90,0,0
3. 投影：透视/正交

---

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;
}
}

Answer 2

我想出了这个脚本（我把它附加到相机上）：

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;
}

Answer 3

帕维尔的回答给了我很多帮助，所以想与社区分享我的解决方案，以防其他人帮助他们。我的场景是带有正交相机的3D世界。我正在研究一种自上而下的RTS风格。我希望平移和缩放像谷歌地图一样工作，当您平移和缩放时，鼠标总是停留在地图上的同一位置。这个脚本为我实现了这个目标，并且希望它足够强大，可以为其他人工作。需要。我还没有经过一段时间的测试，但是我对它的评论是为了让初学者学习。

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;
    }
}

Answer 4

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;
    }
}

Answer 5

根据 Pavel 的回答，我简化了脚本并删除了用超过一根手指触摸并松开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);
    }
}