旋屏

创建一个材质球

创建一个shader命名为ScreenRot

创建C#脚本，命名ScreenRot

给相机添加C#脚本并将材质球拖到脚本上

 

给材质球添加shader脚本

Shader "Lpy/ScreenRot"

{

        Properties

        {

                _MainTex ("Main Tex", 2D) = "white" {}

                _Rot ("Rotation", float) = 0

        }

         

        SubShader

        {

                Tags {"Queue"="Geometry"}

                 

                Pass

                {

                        Tags { "LightMode"="ForwardBase" }

                        ZWrite Off

                         

                        CGPROGRAM

                        #pragma vertex vert 

                        #pragma fragment frag

                        #include "UnityCG.cginc"

                        #define PI 3.14159265358979 

                         

                        sampler2D _MainTex;

                        float _Rot;

                         

                        struct a2v

                        { 

                            float4 vertex : POSITION;

                            float3 texcoord : TEXCOORD0;

                        }; 

                         

                        struct v2f

                        { 

                            float4 pos : SV_POSITION;

                            float2 uv : TEXCOORD0;

                        }; 

                         

                        v2f vert (a2v v)

                        { 

                                v2f o; 

                                o.pos = mul(UNITY_MATRIX_MVP, v.vertex); 

                                o.uv = v.texcoord;

                                return o;

                        } 

                         

                        fixed4 frag (v2f i) : SV_Target

                        {

                                //与中心点(0.5,0.5)的距离

                                float distance = sqrt((i.uv.x - 0.5)*(i.uv.x - 0.5) +(i.uv.y - 0.5)*(i.uv.y - 0.5));

                                //距离越大，旋转角度越大

                                _Rot *=distance;

                                //计算旋转角度

                                float angle = step(i.uv.x,0.5)*PI+ atan((i.uv.y - 0.5)/(i.uv.x - 0.5)) + _Rot;

                                //计算坐标

                                i.uv.x = 0.5 +   distance *cos(angle);

                                i.uv.y = 0.5 +   distance *sin(angle);

 

                                fixed4 c = tex2D(_MainTex, i.uv);

                                return c;

                        }

                        ENDCG

                } 

        }

        FallBack "Specular"

}

 

给摄像机添加C#脚本

using UnityEngine;

 

using System.Collections;

public class ScreenRot : MonoBehaviour

{

    public Material mtl;

    public float rot;

 

    // Update is called once per frame

 

    void Update()

    {

        rot += 0.1f;

    }

 

 

    void OnRenderImage(RenderTexture src, RenderTexture dest)

    {

        if (rot == 0.0)

            return;

 

        mtl.SetFloat("_Rot", rot);

        Graphics.Blit(src, dest, mtl);

    }

}

 

效果图：