1 using UnityEngine;2 using System.Collections;3 using System.Collections.Generic;4 // <summary>5 /// This is used to decide how the camera rendering result to draw to screen.6 /// </summary>7 public enum Camera2DStretchMode8 {9     None,10     StretchFit,11     AspectStretchFit,12 }13 14 /// <summary>15 /// A Camera2D is a camera through which the player views the world.16 /// </summary>17 [ExecuteInEditMode]18 [RequireComponent(typeof(Camera))]19 public class MyCamera : MonoBehaviour20 {21     public static Rect cameraRect;22     /// <summary>23     /// The width of the target screen window in pixels.24     /// </summary>25     public float screenWidth = 800;26 27     /// <summary>28     /// The height of the target screen window in pixels.29     /// </summary>30     public float screenHeight = 600;31 32     /// <summary>33     /// Camera's half-size in orthographic mode34     /// </summary>35     public float orthographicSize36     {37         get38         {39             return _orthographicSize;40         }41 42         set43         {44             _orthographicSize = value;45 46             float aspect = (float)screenWidth / (float)screenHeight;47 48             screenHeight = 2f * _orthographicSize;49             screenWidth = screenHeight * aspect;50         }51     }52 53     [SerializeField]54     private float _orthographicSize = 300;55 56     /// <summary>57     /// This is used to decide how the camera rendering result to draw to screen.58     /// </summary>59     public Camera2DStretchMode stretchMode = Camera2DStretchMode.StretchFit;60 61 62 63     void Reset()64     {65 66     }67 68 69 70     void OnDestroy()71     {72 73     }74 75 76     private bool isOpenGL = false;77     void Awake()78     {79     }80 81 82     void resetCamera()83     {84         orthographicSize = screenHeight * 0.5f;85 86         camera.orthographic = true;87         camera.orthographicSize = screenHeight * 0.5f;88         camera.aspect = (float)screenWidth / (float)screenHeight;89 90 91         int mask = 1;92         int i = 0;93 94         float hw = screenWidth * 0.5f;95         float hh = screenHeight * 0.5f;96 97 98         if (isOpenGL)99             camera.projectionMatrix = Matrix4x4.Ortho(-hw, hw, -hh, hh, 0.0f, 1024f);
100         else
101         {
102             camera.projectionMatrix = Matrix4x4.Ortho(-hw + 0.5f, hw + 0.5f, -hh - 0.5f, hh - 0.5f, -0.01f, 1024f);
103         }
104
105
106
107         if (Screen.width <= 0f || Screen.height <= 0f)
108             return;
109
110
111         if (stretchMode == Camera2DStretchMode.None)
112         {
113             camera.pixelRect = new Rect((Screen.width - screenWidth) * 0.5f, (Screen.height - screenHeight) * 0.5f, screenWidth, screenHeight);
114         }
115
116         if (stretchMode == Camera2DStretchMode.StretchFit)
117         {
118             camera.pixelRect = new Rect(0f, 0f, Screen.width, Screen.height);
119         }
120
121         if (stretchMode == Camera2DStretchMode.AspectStretchFit)
122         {
123             float cameraAspect = (float)screenWidth / (float)screenHeight;
124             float screenAspect = (float)Screen.width / (float)Screen.height;
125
126             if (screenAspect >= cameraAspect)
127             {
128                 float h = Screen.height;
129                 float w = Screen.height * cameraAspect;
130                 camera.pixelRect = new Rect((Screen.width - w) * 0.5f, 0f, w, h);
131             }
132             else
133             {
134                 float w = Screen.width;
135                 float h = w * ((float)screenHeight / (float)screenWidth);
136                 camera.pixelRect = new Rect(0, (Screen.height - h) * 0.5f, w, h);
137             }
138
139         }
140
141         cameraRect = camera.pixelRect;
142     }
143
144
145     void OnPreRender()
146     {
147         resetCamera();
148
149     }
150
151
152
153     void OnEnable()
154     {
155         isOpenGL = SystemInfo.graphicsDeviceName.ToUpper().IndexOf("OPENGL") >= 0;
156         resetCamera();
157     }
158 }