unity2D平面摄像机滑动缩放
比如2D游戏 地图很大，像植物大战僵尸关卡选择界面，需要对可见的区域进行滑动，缩放等，
1….滑动：通过正交摄像机的orthographicSize和位置和实际大小（可视范围大小），计算出距离世界坐标原点偏移量 来计算出位置
2….缩放，对正交相机的orthographicSize进行修改，达到放缩目的。同样也要计算摄像机实际大小（）可视范围大小）
3…..正交相机大小的算法 摄像机实际视界宽度（米）=size*2*屏幕宽高比
当然该方法不限于正交相机 透视相机也可以利用这种思路来计算，当然还要考虑像素和米的换算关系，以下代码块像素米比例是1，即1像素=1米
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
// for map mouse and touch slide and zoom
[RequireComponent(typeof(Camera))]
public class MapCameraSlider : MonoBehaviour
{
Camera camera = null;
float SCREEN_WIDTH = 1136f;//屏幕宽度
float SCREEN_HEIGHT = 640f; // 屏幕高度
const float max_allow_width = 1024f * 3f; // 最大允许滑动的宽度
const float max_allow_height = 1024f * 3f; // 最大允许滑动的高度
float distanceScale;
Vector3 pos1;
Vector3 pos2;
const float SCALEPOSTION = 1f; // 全局位置缩放大小
bool touchBeg = false;
void Start()
{
SCREEN_HEIGHT = Screen.height;
SCREEN_WIDTH = Screen.width;
camera = this.GetComponent<Camera>();
if (camera == null)
{
Debug.LogError("need camera component");
}
}
void Update()
{
if (touchBeg)
{
timeTouch += Time.deltaTime;
}
// ------------------------------------for mobile touch input
if (Input.touchCount == 1)
{ // slide
var data = Input.GetTouch(0);
this.Slide(data.deltaPosition * SCALEPOSTION);
pos1 = Vector3.zero;
pos2 = Vector3.zero;
distanceScale = 0f;
if (data.phase == TouchPhase.Began)
{
StopAllCoroutines();
touch_beg = data.deltaPosition * SCALEPOSTION;
timeTouch = 0.000001f;
touchBeg = true;
}
if (data.phase == TouchPhase.Ended)
{
touchBeg = false;
this.StartAutoSlide(touch_beg, data.position);
}
}
else if (Input.touchCount == 2)
{// scale
touchBeg = false;
var d1 = Input.GetTouch(0);
var d2 = Input.GetTouch(1);
if (d1.phase == TouchPhase.Began)
{
pos1 = d1.position;
distanceScale = Vector3.Distance(pos1, pos2);
}
if (d2.phase == TouchPhase.Began)
{
pos2 = d2.position;
distanceScale = Vector3.Distance(pos1, pos2);
}
if (pos2 != Vector3.zero && pos2 != Vector3.zero)
{
float dis = Vector3.Distance(pos1, pos2);
if (d1.phase == TouchPhase.Moved || d2.phase == TouchPhase.Moved)
{
if (dis > distanceScale)
{
this.ZoomOut(Time.deltaTime * 500f);
}
else if (dis < distanceScale)
{
this.ZoomIn(Time.deltaTime * 500f);
}
}
distanceScale = dis;
}
}
else
{
touchBeg = false;
pos1 = Vector3.zero;
pos2 = Vector3.zero;
distanceScale = 0f;
}
//--------------------------------- for pc mouse input
//slide
if (Input.GetMouseButton(0))
{
if (lastMousePos == Vector2.zero)
{
timeTouch = 0.000001f;
StopAllCoroutines();
lastMousePos = Input.mousePosition;
touch_beg = lastMousePos;
return;
}
else
{
timeTouch += Time.deltaTime;
Vector2 pos = Input.mousePosition;
this.Slide(1.25f * (pos - lastMousePos));
lastMousePos = pos;
}
}
else
{
if (lastMousePos != Vector2.zero)
{
this.StartAutoSlide(touch_beg, Input.mousePosition);
}
lastMousePos = Vector2.zero;
}
//----------------------for pc zoom
if (Input.GetAxis("Mouse ScrollWheel") < 0)
{
this.ZoomOut(Time.deltaTime * 500f);
this.Slide(0f, 0f);
}
//Zoom in
if (Input.GetAxis("Mouse ScrollWheel") > 0)
{
this.ZoomIn(Time.deltaTime * 500f);
this.Slide(0f, 0f);
}
}
float maxtime = 3f;
//开始惯性动画
void StartAutoSlide(Vector2 orign, Vector2 ended)
{
if (Mathf.Abs(timeTouch) < 0.01f)
{
return;
}
maxtime = 3f;
StopAllCoroutines();
Debug.Log("slide map ,speed = " + (Vector2.Distance(orign, ended) / timeTouch / 100f) + " touchTime=" + timeTouch + " posended" + ended + " beg" + orign);
StartCoroutine(RunSliderAction(ended.x - orign.x, ended.y - orign.y, Vector2.Distance(orign, ended) / timeTouch / 100f));
timeTouch = 0.000001f;
}
Vector2 touch_beg;
float timeTouch = 0.000001f;
IEnumerator RunSliderAction(float dx, float dy, float speed)
{
float time = 0f;
float dis = 0f;
while (time < maxtime && speed >= 0f)
{
yield return new WaitForEndOfFrame();
time += Time.deltaTime;
dis += Time.deltaTime * 0.01f;
// Debug.LogError(pos + " " + time + " speed=" + speed);
speed -= Time.deltaTime * 10f;
this.Slide(Time.deltaTime * speed * dx, dy * Time.deltaTime * speed);
}
}
Vector2 lastMousePos = Vector2.zero;
//滑动接口，参数是偏移量
void Slide(Vector2 dp)
{
this.Slide(dp.x, dp.y);
}
//滑动接口，参数是偏移量
void Slide(float dx, float dy)
{
dx = -dx;
dy = -dy;
var pos = transform.position;
pos.x += dx;
pos.y += dy;
transform.position = pos;
//实际宽度
float real_width = camera.orthographicSize * 2 * SCREEN_WIDTH / SCREEN_HEIGHT;
float real_height = real_width * SCREEN_HEIGHT / SCREEN_WIDTH;
//process edge
if (transform.position.x <= real_width / 2f)
{//x left
this.SetPosX(0);
}
if (transform.position.x >= max_allow_width - real_width / 2f)
{// x right
this.SetPosX(max_allow_width - real_width);
}
if (transform.position.y <= real_height / 2f)
{// y up
this.SetPosY(0);
}
if (transform.position.y >= max_allow_height - real_height / 2f)
{// y down
this.SetPosY(max_allow_height - real_height);
}
}
//放大接口
void ZoomOut(float delta)
{
camera.orthographicSize = camera.orthographicSize + delta;
float real_width = camera.orthographicSize * 2 * SCREEN_WIDTH / SCREEN_HEIGHT;
float real_height = real_width * SCREEN_HEIGHT / SCREEN_WIDTH;
float max_size = max_allow_width * SCREEN_HEIGHT / 2f / SCREEN_WIDTH;
if (real_width >= max_allow_width)
{
camera.orthographicSize = max_size;
}
}
//缩小接口
void ZoomIn(float delta)
{
camera.orthographicSize = camera.orthographicSize - delta;
float real_width = camera.orthographicSize * 2 * SCREEN_WIDTH / SCREEN_HEIGHT;
float real_height = real_width * SCREEN_HEIGHT / SCREEN_WIDTH;
float min_size = 150f;
if (camera.orthographicSize <= min_size)
{
camera.orthographicSize = min_size;
}
}
// 设置x偏移量，偏移量是从世界坐标原点开始计算
void SetPosX(float offsetX)
{
float real_width = camera.orthographicSize * 2 * SCREEN_WIDTH / SCREEN_HEIGHT;
float real_height = real_width * SCREEN_HEIGHT / SCREEN_WIDTH;
var posOld = transform.position;
transform.position = new Vector3(real_width / 2f + offsetX, posOld.y, posOld.z);
}
// 设置y偏移量，偏移量是从世界坐标原点开始计算
void SetPosY(float offsetY)
{
float real_width = camera.orthographicSize * 2 * SCREEN_WIDTH / SCREEN_HEIGHT;
float real_height = real_width * SCREEN_HEIGHT / SCREEN_WIDTH;
var posOld = transform.position;
transform.position = new Vector3(posOld.x, offsetY + real_height / 2f, posOld.z);
}
}