// Upgrade NOTE: replaced '_Object2World' with 'unity_ObjectToWorld'
// Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with 'UnityObjectToClipPos(*)'

Shader "MyShader/Water"
{
    Properties
    {
        _farColor("far-Color", Color) = (1,1,1,1)
        _ColorStrong ("Color-Change", Range (0.1, 2)) = 1
        _nearColor("near-Color", Color) = (1,1,1,1)
        _MainTex("zhezhao-R,wave-G,NoiseScale-B", 2D) = "white" {}
        _wave("waveScale-x,WaveSpeed-y     NoiseScale-z,NoiseSpeed-w",vector)=(1.7,0.02,7.3,0.04)
        _transparent("transparent", Range(0.5, 1)) = 1
        _opaque("near-opaque", Range(0, 0.8)) = 0
        _EColor("EnvironmentalColor", Color) = (1,1,1,1)
    }

    SubShader
    {
        tags{"Queue" = "Transparent" "RenderType" = "Transparent" "IgnoreProjector" = "True"}
        Blend SrcAlpha OneMinusSrcAlpha
        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #pragma multi_compile_fog 
            #include "UnityCG.cginc"
            sampler2D _MainTex;
            fixed4 _MainTex_ST,_farColor,_nearColor,_EColor,_wave;
            fixed _ColorStrong,_transparent,_opaque;

            struct a2v {
                float4 vertex : POSITION;
                fixed4 color : COLOR;
                fixed4 texcoord : TEXCOORD0;
            };

            struct v2f {
                float4 pos : POSITION;
                fixed2 uv : TEXCOORD0;
                fixed4 color : COLOR;
                fixed diff : TEXCOORD1;
                UNITY_FOG_COORDS(2)
            };

            v2f vert(a2v v){
                v2f o;
                o.pos = UnityObjectToClipPos(v.vertex);
                o.uv = v.texcoord.xy;
                o.diff = 0.5;
                o.color = v.color;
                UNITY_TRANSFER_FOG(o,o.pos);
                return o;
            }

            half4 frag(v2f i):COLOR
            {
                fixed2 waveOffset =(tex2D(_MainTex, i.uv.xy*_wave.z + float2(0, _Time.y * _wave.w)).b + tex2D(_MainTex, i.uv.xy*_wave.z + float2(_Time.y * _wave.w, 0)).b);

                fixed2 ruv = float2(i.uv.x, 1 - i.uv.y) + waveOffset * 0.01;
                float4 tex  = tex2D (_MainTex, ruv.xy*float2(_wave.x,_wave.x)+float2(0, _Time.y * _wave.y)) ;
                fixed3 near = i.diff * _ColorStrong;
                fixed3 far = max((1 - near), 0);
                fixed3 ap = i.diff*_opaque;
                float4 result;
                result.rgb = (far*_EColor*tex.g + far*_farColor  + near*_nearColor);
                result.a = _transparent-ap;//
                float4 c =  result*i.color;

                UNITY_APPLY_FOG(i.fogCoord, c);
                return c;
            }

            ENDCG
        }
    }
}