Unity中做放大镜 效果

孙广东  2015.8.16

事实上和 小地图都几乎相同了。

还是要借助 还有一个相机

目的: 这篇文章的主要目的是  要给你一个想法  怎样做放大境效果 。

在unity中能够简单的实现放大镜效果啊 . 那么如今就来一步一步实现这个：

创建一个摄像机对象。设置 projection 类型为 perspective 或者 orthographic.

设置相机的 orthographicSize 或者 fieldOfView   (依赖于相机的 projection 类型 ).

设置其 pixelrect  . 比如假设您想要在你鼠标位置显示放大境  和其大小是 100 x 100 , 然后设置pixelrect 为 :

magnifyCamera.pixelRect = new Rect (Input.mousePosition.x – 100f / 2.0f, Input.mousePosition.y – 100f / 2.0f, 100f, 100f);

设置相机的位置。

比如 假设你想在 你的鼠标位置显示放大镜效果  。那么设置相机的位置为 mousePosition世界点。

你能看到终于的效果图：

以下的 C# 脚本将创建一个  MagnifyGlass。并将它移动到 mousePosition位置 。

MagnifyGlass 脚本:   加入到一个空的游戏对象。

using UnityEngine;
using System.Collections;

public class MagnifyGlass : MonoBehaviour
{
private Camera magnifyCamera;
private GameObject magnifyBorders;
private LineRenderer LeftBorder, RightBorder, TopBorder, BottomBorder; // Reference for lines of magnify glass borders
private float MGOX,MG0Y; // Magnify Glass Origin X and Y position
private float MGWidth = Screen.width/5f,MGHeight = Screen.width/5f; // Magnify glass width and height
private Vector3 mousePos;

void Start ()
{
createMagnifyGlass ();
}
void Update ()
{
// Following lines set the camera's pixelRect and camera position at mouse position
magnifyCamera.pixelRect = new Rect (Input.mousePosition.x - MGWidth / 2.0f, Input.mousePosition.y - MGHeight / 2.0f, MGWidth, MGHeight);
mousePos = getWorldPosition (Input.mousePosition);
magnifyCamera.transform.position = mousePos;
mousePos.z = 0;
magnifyBorders.transform.position = mousePos;
}

// Following method creates MagnifyGlass
private void createMagnifyGlass()
{
GameObject camera = new GameObject("MagnifyCamera");
MGOX = Screen.width / 2f - MGWidth/2f;
MG0Y = Screen.height / 2f - MGHeight/2f;
magnifyCamera = camera.AddComponent<Camera>();
magnifyCamera.pixelRect = new Rect(MGOX, MG0Y, MGWidth, MGHeight);
magnifyCamera.transform.position = new Vector3(0,0,0);
if(Camera.main.isOrthoGraphic)
{
magnifyCamera.orthographic = true;
magnifyCamera.orthographicSize = Camera.main.orthographicSize / 5.0f;//+ 1.0f;
createBordersForMagniyGlass ();
}
else
{
magnifyCamera.orthographic = false;
magnifyCamera.fieldOfView = Camera.main.fieldOfView / 10.0f;//3.0f;
}

}

// Following method sets border of MagnifyGlass
private void createBordersForMagniyGlass()
{
magnifyBorders = new GameObject ();
LeftBorder = getLine ();
LeftBorder.SetVertexCount(2);
LeftBorder.SetPosition(0,new Vector3(getWorldPosition(new Vector3(MGOX,MG0Y,0)).x,getWorldPosition(new Vector3(MGOX,MG0Y,0)).y-0.1f,-1));
LeftBorder.SetPosition(1,new Vector3(getWorldPosition(new Vector3(MGOX,MG0Y+MGHeight,0)).x,getWorldPosition(new Vector3(MGOX,MG0Y+MGHeight,0)).y+0.1f,-1));
LeftBorder.transform.parent = magnifyBorders.transform;
TopBorder = getLine ();
TopBorder.SetVertexCount(2);
TopBorder.SetPosition(0,new Vector3(getWorldPosition(new Vector3(MGOX,MG0Y+MGHeight,0)).x,getWorldPosition(new Vector3(MGOX,MG0Y+MGHeight,0)).y,-1));
TopBorder.SetPosition(1,new Vector3(getWorldPosition(new Vector3(MGOX+MGWidth,MG0Y+MGHeight,0)).x,getWorldPosition(new Vector3(MGOX+MGWidth,MG0Y+MGHeight,0)).y,-1));
TopBorder.transform.parent = magnifyBorders.transform;
RightBorder = getLine ();
RightBorder.SetVertexCount(2);
RightBorder.SetPosition(0,new Vector3(getWorldPosition(new Vector3(MGOX+MGWidth,MG0Y+MGWidth,0)).x,getWorldPosition(new Vector3(MGOX+MGWidth,MG0Y+MGWidth,0)).y+0.1f,-1));
RightBorder.SetPosition(1,new Vector3(getWorldPosition(new Vector3(MGOX+MGWidth,MG0Y,0)).x,getWorldPosition(new Vector3(MGOX+MGWidth,MG0Y,0)).y-0.1f,-1));
RightBorder.transform.parent = magnifyBorders.transform;
BottomBorder = getLine ();
BottomBorder.SetVertexCount(2);
BottomBorder.SetPosition(0,new Vector3(getWorldPosition(new Vector3(MGOX+MGWidth,MG0Y,0)).x,getWorldPosition(new Vector3(MGOX+MGWidth,MG0Y,0)).y,-1));
BottomBorder.SetPosition(1,new Vector3(getWorldPosition(new Vector3(MGOX,MG0Y,0)).x,getWorldPosition(new Vector3(MGOX,MG0Y,0)).y,-1));
BottomBorder.transform.parent = magnifyBorders.transform;
}

// Following method creates new line for MagnifyGlass's border
private LineRenderer getLine()
{
LineRenderer line = new GameObject("Line").AddComponent<LineRenderer>();
line.material = new Material(Shader.Find("Diffuse"));
line.SetVertexCount(2);
line.SetWidth(0.2f,0.2f);
line.SetColors(Color.black, Color.black);
line.useWorldSpace = false;
return line;
}
private void setLine(LineRenderer line)
{
line.material = new Material(Shader.Find("Diffuse"));
line.SetVertexCount(2);
line.SetWidth(0.2f,0.2f);
line.SetColors(Color.black, Color.black);
line.useWorldSpace = false;
}

// Following method calculates world's point from screen point as per camera's projection type
public Vector3 getWorldPosition(Vector3 screenPos)
{
Vector3 worldPos;
if(Camera.main.isOrthoGraphic)
{
worldPos = Camera.main.ScreenToWorldPoint (screenPos);
worldPos.z = Camera.main.transform.position.z;
}
else
{
worldPos = Camera.main.ScreenToWorldPoint (new Vector3 (screenPos.x, screenPos.y, Camera.main.transform.position.z));
worldPos.x *= -1;
worldPos.y *= -1;
}
return worldPos;
}
}

相信你能够通过这个 做的更好。