WaterFlush/Assets/Enviro 3 - Sky and Weather/Resources/Shader/ReflectionProbe/EnviroCubemapBlur.shader

// Unity built-in shader source. Copyright (c) 2016 Unity Technologies. MIT license (see license.txt)

Shader "Hidden/EnviroCubemapBlur" {
    Properties {
        _MainTex ("Main", CUBE) = "" {}
        _Texel ("Texel", Float) = 0.0078125
        _Level ("Level", Float) = 0.
    }

    CGINCLUDE 
    #pragma vertex vert
    #pragma fragment frag
    #include "UnityCG.cginc"
    #include "HLSLSupport.cginc"

    struct v2f {
        half4 pos : SV_POSITION;
        half4 uvw : TEXCOORD0;
    };

    v2f vert(appdata_base v)
    {
        v2f o;
        o.pos = UnityObjectToClipPos(v.vertex);
        o.uvw = v.texcoord;
        return o;
    }

    UNITY_DECLARE_TEXCUBE(_MainTex);
    half _Level; // Workaround for Metal driver bug: please keep this uniform aligned to 4 bytes (case 899153)
    half _Texel;

    #define zero    half3(0., 0., 0.)
    #define one     half3(1., 1., 1.)
    #define two     half3(2., 2., 2.)

    half3 fold(half3 st, half3 face)
    {
        half3 c = min(max(st, -one), one);
        half3 f = abs(st - c);
        half m = max(max(f.x, f.y), f.z);
        return c - m*face;
    }

    half3 gauss(half d)
    {
        // compute coefficients for positions 0., 1.*d/.5 and 2.*d/.5
        // this assumes a sigma of .5 for a density of 1.
        half3 v = half3(0., 1.*d, 2.*d);
        return exp(-v*v);
    }

    half4 frag(v2f i) : SV_Target
    {
    #if (SHADER_TARGET < 30)
        return UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, i.uvw.xyz, _Level);
    #else

        half3 st;

        half3 face = abs(i.uvw.xyz)==one ? i.uvw.xyz : zero;
        half3 u = face.zxy*_Texel;
        half3 v = face.yzx*_Texel;
        half4 s = float4(i.uvw.xyz*(one - abs(face)), 0.);

        // modulate coefficients based on position (texel density on projected sphere)
        half w = 1. / sqrt(1. + dot(s.xyz, s.xyz));
        half3 C = gauss(w*w*w);

        half4 s1, s2, s3;
        half3 c;

        s = 0.;
        w = 0.;

        // first row

        c = C.xyz*C.zzz;

        st = i.uvw.xyz - 2.*u - 2.*v;
        st = fold(st, face);
        s3 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz - 1.*u - 2.*v;
        st = fold(st, face);
        s2 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz - 2.*v;
        st = fold(st, face);
        s1 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz + 1.*u - 2.*v;
        st = fold(st, face);
        s2 += UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz + 2.*u - 2.*v;
        st = fold(st, face);
        s3 += UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        w += c.x + dot(c.yz, two.yz);
        s1 = c.x*s1 + c.y*s2;
        s += c.z*s3;
        s += s1;

        // second row

        c = C.xyz*C.yyy;

        st = i.uvw.xyz + 2.*u - 1.*v;
        st = fold(st, face);
        s3 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz + 1.*u - 1.*v;
        st = fold(st, face);
        s2 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz - 1.*v;
        st = fold(st, face);
        s1 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz - 1.*u - 1.*v;
        st = fold(st, face);
        s2 += UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz - 2.*u - 1.*v;
        st = fold(st, face);
        s3 += UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        w += c.x + dot(c.yz, two.yz);
        s1 = c.x*s1 + c.y*s2;
        s += c.z*s3;
        s += s1;

        // third row

        c = C.xyz*C.xxx;

        st = i.uvw.xyz - 2.*u;
        st = fold(st, face);
        s3 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz - 1.*u;
        st = fold(st, face);
        s2 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz;
        s1 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz + 1.*u;
        s2 += UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz + 2.*u;
        st = fold(st, face);
        s3 += UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        w += c.x + dot(c.yz, two.yz);
        s1 = c.x*s1 + c.y*s2;
        s += c.z*s3;
        s += s1;

        // fourth row

        c = C.xyz*C.yyy;

        st = i.uvw.xyz + 2.*u + 1.*v;
        st = fold(st, face);
        s3 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz + 1.*u + 1.*v;
        st = fold(st, face);
        s2 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz + 1.*v;
        st = fold(st, face);
        s1 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz - 1.*u + 1.*v;
        st = fold(st, face);
        s2 += UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz - 2.*u + 1.*v;
        st = fold(st, face);
        s3 += UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        w += c.x + dot(c.yz, two.yz);
        s1 = c.x*s1 + c.y*s2;
        s += c.z*s3;
        s += s1;

        // fifth row

        c = C.xyz*C.zzz;

        st = i.uvw.xyz - 2.*u + 2.*v;
        st = fold(st, face);
        s3 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz - 1.*u + 2.*v;
        st = fold(st, face);
        s2 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz + 2.*v;
        st = fold(st, face);
        s1 = UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz + 1.*u + 2.*v;
        st = fold(st, face);
        s2 += UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        st = i.uvw.xyz + 2.*u + 2.*v;
        st = fold(st, face);
        s3 += UNITY_SAMPLE_TEXCUBE_LOD(_MainTex, st, _Level);

        w += c.x + dot(c.yz, two.yz);
        s1 = c.x*s1 + c.y*s2;
        s += c.z*s3;
        s += s1;

        //return half4(C.zzz, 1.);
        return s/w;
    #endif
    }
    ENDCG
    SubShader {
        Tags { "RenderType"="Opaque" }
        LOD 200
        Pass {
            ZTest Always
            Blend Off
            AlphaTest off
            Cull Off
            ZWrite Off
            Fog { Mode off }
            CGPROGRAM
            #pragma target 3.0
            ENDCG
        }
    }

    SubShader {
        Tags { "RenderType"="Opaque" }
        LOD 200
        Pass {
            ZTest Always
            Blend Off
            AlphaTest off
            Cull Off
            ZWrite Off
            Fog { Mode off }
            CGPROGRAM
            #pragma target 2.0
            ENDCG
        }
    }
}