Shader "Custom/VertexColorCurved" {

    Properties {

        // Shader需要的6个参数

        _MainTex ("Base (RGB)", 2D) = "white" {}

        _QOffset ("Offset", Vector) = (,,,)

        _Dist ("Distance", Float) = 100.0

        _BrightnessAmount ("Brightness Amount", Float) = 1.0

        _SaturationAmount ("Saturation Amount", Float) = 1.0

        _ContrastAmount ("Contrast Amount", Float) = 1.0

    }

    SubShader {

        Tags { "Queue" = "Transparent"}

        Pass

        {

            Blend SrcAlpha OneMinusSrcAlpha

            CGPROGRAM

            #pragma vertex vert

            #pragma fragment frag

            #include "UnityCG.cginc"

            sampler2D _MainTex;

            float4 _QOffset;

            float _Dist;

            fixed _BrightnessAmount;

            fixed _SaturationAmount;

            fixed _ContrastAmount;

            float _OpacityAmount;

            struct v2f {

                float4 pos : SV_POSITION;

                float4 uv : TEXCOORD0;

                float3 viewDir : TEXCOORD1;

                fixed4 color : COLOR;

            };

            v2f vert (appdata_full v)

            {

                   v2f o;

                   float4 vPos = mul (UNITY_MATRIX_MV, v.vertex);

                float zOff = vPos.z/_Dist;

                   vPos += _QOffset*zOff*zOff;

                   o.pos = mul (UNITY_MATRIX_P, vPos);

                   o.uv = v.texcoord;

　　　　　　　　　　　//o.color.rgb = v.color.rgb;  // 取顶点色

                   return o;

            }

            float3 ContrastSaturationBrightness (float3 color, float brt, float sat, float con) {

                // Increase or decrease these values to

                // adjust r, g and b color channels separately

                float avgLumR = 0.5;

                float avgLumG = 0.5;

                float avgLumB = 0.5;  

                // Luminance coefficients for getting luminance from the image

                float3 LuminanceCoeff = float3 (0.2125, 0.7154, 0.0721);  

                // Operation for brightmess

                float3 avgLumin = float3 (avgLumR, avgLumG, avgLumB);

                float3 brtColor = color * brt;

                float intensityf = dot (brtColor, LuminanceCoeff);

                float3 intensity = float3 (intensityf, intensityf, intensityf);  

                // Operation for saturation

                float3 satColor = lerp (intensity, brtColor, sat);  

                // Operation for contrast

                float3 conColor = lerp (avgLumin, satColor, con);  

                return conColor;

            }  

            half4 frag (v2f i) : COLOR0

            {

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

//                  // Apply vertex color

//                  renderTex.rgb *= i.color.rgb;  // 顶点色和贴图混合

                // Apply the brightness, saturation, contrast operations

                renderTex.rgb = ContrastSaturationBrightness (renderTex.rgb, _BrightnessAmount, _SaturationAmount, _ContrastAmount);

                return renderTex;

            }

            ENDCG

        }

    }

    FallBack "Diffuse"

}