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有两种方法可以让您的相机绕一个点运行。在你做任何其他事情之前，在 Unity 中创建一个空的 GameObject 并将它设置在你希望你的相机围绕它运行的固定点。确保游戏对象在相机的视线内。然后将您的相机设置为 Empty GameObject。
对于简单（但更严格）的方法，请将您的 TouchCamera 脚本附加到 Empty GameObject。从您的相机中删除 TouchCamera 脚本。现在将这一行 public Camera camera 添加到脚本中 Update 方法的开头上方。在您的脚本中，将所有出现的GetComponent<Camera>() 替换为camera。保存您的脚本并返回 Unity。最后，单击您的 Empty GameObject 并将您的 Camera 拖到 TouchCamera 组件中的 Serialized Camera 字段中。这种方法实质上是将相机的控制权转移到了 Empty GameObject。
对于更复杂（但更灵活）的方法，创建一个新的 C# 脚本并将其命名为“CameraControl”。然后将以下代码复制并粘贴到脚本中（替换任何已经存在的代码）。
using UnityEngine;
using UnityEngine.UI;
using System;
using System.Collections;
public class CameraControl : MonoBehaviour {
Vector2?[] oldTouchPositions = {
null,
null
};
Vector2 oldTouchVector;
float oldTouchDistance;
public Transform CenterOfRotation;
public Camera camera;
private Vector2 actualCenter;
private Vector2 prevTouchDelta;
private Vector3 prevMousePosition;
private bool rotate;
void Start()
{
//swap with below commented line for y rotation.
actualCenter = new Vector2(CenterOfRotation.position.x, CenterOfRotation.position.z);
//actualCenter = new Vector2(CenterOfRotation.position.x, CenterOfRotation.position.y);
}
void Update() {
if(!rotate){
if (Input.touchCount == 0) {
oldTouchPositions[0] = null;
oldTouchPositions[1] = null;
}
else if (Input.touchCount == 1) {
if (oldTouchPositions[0] == null || oldTouchPositions[1] != null) {
oldTouchPositions[0] = Input.GetTouch(0).position;
oldTouchPositions[1] = null;
}
else {
Vector2 newTouchPosition = Input.GetTouch(0).position;
transform.position += transform.TransformDirection((Vector3)((oldTouchPositions[0] - newTouchPosition) * camera.orthographicSize / camera.pixelHeight * 2f));
oldTouchPositions[0] = newTouchPosition;
}
}
else {
if (oldTouchPositions[1] == null) {
oldTouchPositions[0] = Input.GetTouch(0).position;
oldTouchPositions[1] = Input.GetTouch(1).position;
oldTouchVector = (Vector2)(oldTouchPositions[0] - oldTouchPositions[1]);
oldTouchDistance = oldTouchVector.magnitude;
}
else {
Vector2 screen = new Vector2(camera.pixelWidth, camera.pixelHeight);
Vector2[] newTouchPositions = {
Input.GetTouch(0).position,
Input.GetTouch(1).position
};
Vector2 newTouchVector = newTouchPositions[0] - newTouchPositions[1];
float newTouchDistance = newTouchVector.magnitude;
transform.position += transform.TransformDirection((Vector3)((oldTouchPositions[0] + oldTouchPositions[1] - screen) * camera.orthographicSize / screen.y));
//transform.localRotation *= Quaternion.Euler(new Vector3(0, Mathf.Asin(Mathf.Clamp((oldTouchVector.y * newTouchVector.x - oldTouchVector.x * newTouchVector.y) / oldTouchDistance / newTouchDistance, -1f, 1f)) / 0.0174532924f, 0));
camera.orthographicSize *= oldTouchDistance / newTouchDistance;
transform.position -= transform.TransformDirection((newTouchPositions[0] + newTouchPositions[1] - screen) * camera.orthographicSize / screen.y);
oldTouchPositions[0] = newTouchPositions[0];
oldTouchPositions[1] = newTouchPositions[1];
oldTouchVector = newTouchVector;
oldTouchDistance = newTouchDistance;
}
}
}
else{
InwardRotation();
}
}
void OnGUI()
{
rotate = GUILayout.Toggle(rotate, "Toggle For Rotation", "Button");
}
void InwardRotation()
{
//mouse version
if(Input.GetMouseButton(0))
{
//distance from center of screen to touch
Vector3 centerScreen = camera.ViewportToScreenPoint(new Vector3(0.5f, 0.5f, 1));
Vector3 mouseDelta = Input.mousePosition - new Vector3(centerScreen.x, centerScreen.y, 0f);
//if mouse doesn't move very much, don't rotate
if(mouseDelta.sqrMagnitude < 0.1f)
return;
//attempts to make movement smoother
if(prevMousePosition == Vector3.zero)
prevMousePosition = mouseDelta;
//this gets the angle between the current touch and the last touch
float theta = Mathf.Atan2(mouseDelta.y, mouseDelta.x) - Mathf.Atan2(prevMousePosition.y, prevMousePosition.x);
//Gets the rotated coordinates of the camera. Swap with below commented line for y rotation.
Vector2 newPos = RotatedCoordinates(transform.position.x, transform.position.z, theta, CenterOfRotation.position, true);
//Vector2 newPos = RotatedCoordinates(transform.position.x, transform.position.y, theta, CenterOfRotation.position, true);
Debug.Log("New Pos = " + newPos);
//swap with below commented line for y rotation.
transform.localPosition = new Vector3(newPos.x, transform.localPosition.y, newPos.y);
//transform.localPosition = new Vector3(newPos.x, newPos.y, transform.localPosition.z);
transform.LookAt(CenterOfRotation);
prevMousePosition = mouseDelta;
}
if(Input.touches.Length > 0f)
{
//distance from center of screen to touch
Vector3 centerScreen = camera.ViewportToScreenPoint(new Vector3(0.5f, 0.5f, 1));
Vector2 touchDelta = Input.GetTouch(0).position - new Vector2(centerScreen.x, centerScreen.y);
//if mouse doesn't move very much, don't rotate
if(touchDelta.sqrMagnitude < 0.1f)
return;
//attempts to make movement smoother
if(prevTouchDelta == Vector2.zero)
prevTouchDelta = touchDelta;
//this gets the angle between the current touch and the last touch
float theta = Mathf.Atan2(touchDelta.y, touchDelta.x) - Mathf.Atan2(prevTouchDelta.y, prevTouchDelta.x);
//Gets the rotated coordinates of the camera. Swap with below commented line for y rotation.
Vector2 newPos = RotatedCoordinates(transform.position.x, transform.position.z, theta, CenterOfRotation.position, true);
//Vector2 newPos = RotatedCoordinates(transform.position.x, transform.position.y, theta, CenterOfRotation.position, true);
Debug.Log("New Pos = " + newPos);
//swap with below commented line for y rotation.
transform.localPosition = new Vector3(newPos.x, transform.localPosition.y, newPos.y);
//transform.localPosition = new Vector3(newPos.x, newPos.y, transform.localPosition.z);
transform.LookAt(CenterOfRotation);
prevTouchDelta = touchDelta;
}
else{
prevTouchDelta = Vector2.zero;
}
}
/// <summary>
/// This method returns the coordinates of a plane rotated about its origin. It translates a point from one place on a unit circle to another.
/// </summary>
/// <returns>The coordinates.</returns>
/// <param name="x">The x coordinate.</param>
/// <param name="y">The y coordinate.</param>
/// <param name="theta">Theta.</param>
/// <param name="ThetaInRad">If set to <c>true</c> theta in RAD.</param>
public Vector2 RotatedCoordinates(float x, float y, float theta, Vector2 center, bool ThetaInRad = false)
{
if(!ThetaInRad)
theta *= Mathf.Deg2Rad;
Vector2 XY = new Vector2((Mathf.Cos(theta) * (x - center.x) - Mathf.Sin(theta) * (y - center.y)) + center.x, (Mathf.Sin(theta) * (x - center.x) + Mathf.Cos(theta) * (y - center.y)) + center.y);
return XY;
}
}
现在将它附加到您的相机（它应该是空游戏对象的子对象）并删除 TouchCamera 脚本。您会注意到 CameraControl 组件内的两个字段，一个读取“旋转中心”，一个读取“相机”。将 Empty GameObject 和您的相机分别拖到这些字段上。如果您跳过此步骤，此脚本将引发空引用错误。现在只需点击播放。当您单击播放窗口左上角的Toggle For Rotation 按钮时，您将能够通过围绕屏幕中心拖动鼠标指针或单指来旋转相机。您可以从 Empty GameObject 中取消相机的父级，脚本仍然可以工作。您还可以通过提供不同的变换绕空间中的任何点运行。通过一些编辑，您还可以完全消除变换并使用 Vector3 作为世界空间中的参考点，但您需要自己控制相机的实际旋转，而不需要transform.LookAt(CenterOfRotation); 线。您可以通过编辑三行来更改旋转轴，大致位于第 30 行、第 145 行和第 151 行。