跑酷扭曲特效问题

解决跑酷之前项目特效不能扭曲太大问题，引起的特效偏移问题，还有特效输入的颜色值Alpha 值渐变问题。

Shader "Custom/Curveds" {
    Properties {
        _MainTex ("Base (RGB)", 2D) = "white" {}
        _QOffset ("Offset", Vector) = (0,0,0,0)
        _Color ("Main Color", Color) = (1,1,1,1)
        _Brightness ("Brightness", Float) = 0.0
        _Dist ("Distance", Float) = 100.0
    }
    
    SubShader {
       Tags{ "Queue" = "Transparent" "IgnoreProjector" = "True" "RenderType" = "Transparent" }
        Blend SrcAlpha One
        ColorMask RGB
        Cull Off Lighting Off ZWrite Off
        CGPROGRAM
        #pragma surface surf Lambert vertex:vert alphatest:_Cut
       
        struct Input 
        {
             float2 uv_MainTex;
             float4 color :COLOR;
        };
      
        sampler2D _MainTex;
        float4 _QOffset;
        float _Dist;
        float _Brightness;
        float4 _Color;
        void vert (inout appdata_full v) 
        {
            float4 vPos = mul (UNITY_MATRIX_MV, v.vertex);          
            float xsmeh=sin(_WorldSpaceCameraPos.z/120);        
            float zOff = vPos.z/_Dist;
            vPos += _QOffset*zOff*zOff;
            v.vertex = mul(transpose(UNITY_MATRIX_IT_MV), vPos);
            #if SHADER_API_GLES
                v.vertex.xyz*= 1.0;
            #endif
        }
      
        void surf (Input IN, inout SurfaceOutput o) 
        {
            o.Albedo =2.0 * tex2D(_MainTex, IN.uv_MainTex).rgb * _Brightness * _Color.rgb;
            float alpha = 2.0* tex2D(_MainTex, IN.uv_MainTex).a * _Color.a * IN.color.a;
            o.Alpha = alpha; 
        }
        ENDCG
    }
    
    Fallback "Diffuse"
}