[游戏开发-学习笔记]菜鸟慢慢飞(四)-Camera
游戏开发中,主相机应该是最重要的GameObject之一,毕竟游戏呈现给玩家,就是通过它。
相机的使用,在不同的游戏中,有很大的不同。这里总结一下自己学到的一些相关知识。
固定位置-游戏过程中相机的Transform属性不改变。
- 调整好位置后就不要动了,一般使用正交相机,即Camera-Projection选择Orthographic。Unity Manual-Camera
适用:2D游戏。比如飞机大战,消消乐。 - 游戏开始后,相机追踪某一物体,然后固定不动。
游戏开始后,我们才能确定追踪物体的位置,先看代码:
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
1 using UnityEngine; 2 3 public class CameraController : MonoBehaviour 4 { 5 public GameObject player; 6 private Vector3 offset; 7 void Start () 8 { 9 offset = transform.position - player.transform.position; 10 } 11 void LateUpdate () 12 { 13 transform.position = player.transform.position + offset; 14 } 15 }
适用:固定视角的3D游戏。
3D视角-围绕一个中心随意旋转
先看代码:
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
using UnityEngine; public class CameraContorller : MonoBehaviour { /// <summary> /// 追踪目标 /// </summary> public Transform target; /// <summary> /// 旋转速度 /// </summary> public float xSpeed = 200, ySpeed = 200; /// <summary> /// 缩放速度 /// </summary> public float mSpeed = 10; /// <summary> /// 最小/最大限制角度 /// </summary> public float yMinLimit = -50, yMaxLimit = 50; /// <summary> /// 是否使用插值运算 /// </summary> public bool needDamping = true; /// <summary> /// 速度 /// </summary> public float damping = 5.0f; /// <summary> /// 观察距离 /// </summary> private float distance = 2; /// <summary> /// 最小/最大观察距离 /// </summary> private float minDistance = 2, maxDistance = 30; /// <summary> /// 旋转角度 /// </summary> private float x = 0.0f, y = 0.0f; void Start() { Vector3 angles = transform.eulerAngles; x = angles.y; y = angles.x; //根据相机的初始位置初始化距离,最大距离,最小距离; Vector3 offset = transform.position - target.position; distance = offset.magnitude; minDistance = distance / 5; maxDistance = distance * 3; } void LateUpdate() { if (target) { if (Input.GetMouseButton(1))//0-左键,1-右键,2-中键 { x += Input.GetAxis("Mouse X") * xSpeed * 0.02f; y -= Input.GetAxis("Mouse Y") * ySpeed * 0.02f; y = ClampAngle(y, yMinLimit, yMaxLimit); } distance -= Input.GetAxis("Mouse ScrollWheel") * mSpeed; distance = Mathf.Clamp(distance, minDistance, maxDistance); Quaternion rotation = Quaternion.Euler(y, x, 0.0f); Vector3 disVector = new Vector3(0.0f, 0.0f, -distance); Vector3 position = rotation * disVector + target.position; if (needDamping) { transform.rotation = Quaternion.Lerp(transform.rotation, rotation, Time.deltaTime * damping); Vector3 transformTemp = Vector3.Lerp(transform.position, position, Time.deltaTime * damping); if (transformTemp.y <= 0)//如果相机位置在“水平面”以下,强制设置到水平面。 { transform.position = new Vector3(transformTemp.x, 0, transformTemp.z); } else { transform.position = transformTemp; } } else { transform.rotation = rotation; if (position.y <= 0)//如果相机位置在“水平面”以下,强制设置到水平面。 { transform.position = new Vector3(position.x, 0, position.z); } else { transform.position = position; } } } } static float ClampAngle(float angle, float min, float max) { if (angle < -360) angle += 360; if (angle > 360) angle -= 360; return Mathf.Clamp(angle, min, max); } }
大部分3D游戏中,我这样理解:主角看作球心,球半径玩家可以自己改变,相机的位置就在“地面”以上的半球球体上。
上面这段代码基本做到了这个要求,并在相机到“地面”的时候有抬头看的效果。
代码有点问题,开始游戏后相机会跳动两次,暂时放到自己的问题清单中。
其他用法
官方教程Tanks tutorial 中有个不常见的用法。
不管两个Tank如何移动,相机通过前后缩放,大小缩放保证两个Tank肯定在相机视野内。
主要代码:(官方代码写得好啊)
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
private void Move () { // Find the average position of the targets. FindAveragePosition (); // Smoothly transition to that position. transform.position = Vector3.SmoothDamp(transform.position, m_DesiredPosition, ref m_MoveVelocity, m_DampTime); } private void FindAveragePosition () { Vector3 averagePos = new Vector3 (); int numTargets = 0; // Go through all the targets and add their positions together. for (int i = 0; i < m_Targets.Length; i++) { // If the target isn't active, go on to the next one. if (!m_Targets[i].gameObject.activeSelf) continue; // Add to the average and increment the number of targets in the average. averagePos += m_Targets[i].position; numTargets++; } // If there are targets divide the sum of the positions by the number of them to find the average. if (numTargets > 0) averagePos /= numTargets; // Keep the same y value. averagePos.y = transform.position.y; // The desired position is the average position; m_DesiredPosition = averagePos; } private void Zoom () { // Find the required size based on the desired position and smoothly transition to that size. float requiredSize = FindRequiredSize(); m_Camera.orthographicSize = Mathf.SmoothDamp (m_Camera.orthographicSize, requiredSize, ref m_ZoomSpeed, m_DampTime); } private float FindRequiredSize () { // Find the position the camera rig is moving towards in its local space. Vector3 desiredLocalPos = transform.InverseTransformPoint(m_DesiredPosition); // Start the camera's size calculation at zero. float size = 0f; // Go through all the targets... for (int i = 0; i < m_Targets.Length; i++) { // ... and if they aren't active continue on to the next target. if (!m_Targets[i].gameObject.activeSelf) continue; // Otherwise, find the position of the target in the camera's local space. Vector3 targetLocalPos = transform.InverseTransformPoint(m_Targets[i].position); // Find the position of the target from the desired position of the camera's local space. Vector3 desiredPosToTarget = targetLocalPos - desiredLocalPos; // Choose the largest out of the current size and the distance of the tank 'up' or 'down' from the camera. size = Mathf.Max(size, Mathf.Abs(desiredPosToTarget.y)); // Choose the largest out of the current size and the calculated size based on the tank being to the left or right of the camera. size = Mathf.Max(size, Mathf.Abs(desiredPosToTarget.x) / m_Camera.aspect); } // Add the edge buffer to the size. size += m_ScreenEdgeBuffer; // Make sure the camera's size isn't below the minimum. size = Mathf.Max (size, m_MinSize); return size; }
暂时放下的内容
Unity的相机相关: