wip: enki shader

Assets/_Content/Shaders/EnkiBillal/Include/EnkiBiIlal.hlsl

@@ -153,6 +153,74 @@ float WorldStripes()
     return 0;
 }
 
+float WorldDistort(float3 PositionWS, float3 NormalWS, float Angle, float TriplanarBlend)
+{
+    float StripesScale = 60;
+
+    // Octahedral face normals (4 faces + 3 world axes)
+    float3 octaFaceNormals[7] =
+    {
+        normalize(float3(1, 1, 1)),
+        normalize(float3(-1, 1, 1)),
+        normalize(float3(1, -1, 1)),
+        normalize(float3(-1, -1, 1)),
+        float3(1, 0, 0),
+        float3(0, 1, 0),
+        float3(0, 0, 1)
+    };
+
+    // Octahedral blending mask
+    float sharpness = Remap(0, 1, 1, 16, smoothstep(0, .9, TriplanarBlend));
+    float octaMask[7];
+    float hardMax = -1;
+    int hardIdx = 0;
+    for (int i = 0; i < 7; i++)
+    {
+        float d = abs(dot(NormalWS, octaFaceNormals[i]));
+        octaMask[i] = pow(saturate(d), sharpness);
+        if (d > hardMax)
+        {
+            hardMax = d;
+            hardIdx = i;
+        }
+    }
+    float maskSum = 0;
+    for (int i = 0; i < 7; i++)
+        maskSum += octaMask[i];
+    for (int i = 0; i < 7; i++)
+        octaMask[i] /= max(maskSum, 0.0001);
+    float hardFactor = smoothstep(.9, 1, TriplanarBlend);
+    for (int i = 0; i < 7; i++)
+    {
+        float hard = (i == hardIdx) ? 1.0 : 0.0;
+        octaMask[i] = lerp(octaMask[i], hard, hardFactor);
+    }
+    
+    // Patern
+    float stripes = 0;
+    
+    [unroll]
+    for (int i = 0; i < 7; i++)
+    {
+        float3 n = octaFaceNormals[i];
+
+        float3 up = abs(n.y) < 0.999 ? float3(0, 1, 0) : float3(1, 0, 0);
+        float3 tangent = normalize(cross(up, n));
+        float3 bitangent = normalize(cross(n, tangent));
+
+        float angle = i / 7.0 * PI;
+
+        float2 p = RotateUV(float2(dot(PositionWS, tangent), dot(PositionWS, bitangent)), 0, angle) * StripesScale;
+        
+        float stripe = cos(p.x);
+        
+        stripes += stripe * octaMask[i];
+    }
+    
+    return stripes;
+}
+
+
 float ProjectionMask(
     float3 PositionWS,
     float3 CamPositionWS,
@@ -254,12 +322,7 @@ void EnkiBillal_float
     float3 mainLightDir = normalize(float3(1, -1, 1)); //normalize(float3(0, 13, 8) - PositionWS); //float3(0, -1, 0);//normalize(mainLight.direction);
     float lightGradient = dot(normalize(NormalWS), normalize(mainLightDir));
     lightGradient = smoothstep(-.5, 1, lightGradient);
-    float ao = GetScreenSpaceAmbientOcclusion(ScreenUV).directAmbientOcclusion;
-    
-
-    // Triplanar
-
-    //float3 triplanarMask = TriplanarMask(NormalWS, TriplanarBlend);
+    //float ao = GetScreenSpaceAmbientOcclusion(ScreenUV).directAmbientOcclusion;
     
     // Shadow
 
@@ -268,7 +331,7 @@ void EnkiBillal_float
 
     // Grain
 
-    float grain = ValueNoise3DLOD(PositionWS, scaledPositionOS, 600, 3.5);
+    /*float grain = ValueNoise3DLOD(PositionWS, scaledPositionOS, 600, 3.5);
     float grainMin = lerp(.4, .8, shadowMask);
     float grainAtten = Remap(0, 1, grainMin, 1, grain);
 
@@ -276,7 +339,7 @@ void EnkiBillal_float
 
     float dirt = FBMNoise3D(scaledPositionOS, 1, 3, 2, .5);
     float dirtMin = lerp(.2, .7, shadowMask);
-    float dirtAtten = Remap(0, 1, dirtMin, 1, dirt);
+    float dirtAtten = Remap(0, 1, dirtMin, 1, dirt);*/
 
     // Stripes
 
@@ -326,15 +389,30 @@ void EnkiBillal_float
     //float test = FBMNoise3D(PositionWS, 10, 2, 2, .5);
     //float test = RidgedNoise3D(PositionWS, 10, 2, 2, .5);
     
+    float3 pWS = scaledPositionOS;
+    float n0 = PerlinNoise3D(pWS, 2);
+    float distort = WorldDistort(pWS + n0 * .2, NormalWS, 1, TriplanarBlend);
+    float3 p = pWS + n0 * 2 + distort * smoothstep(.5, .7, n0) * .06;
+    float grad = 0;
+    float cell = 0;
+    VoronoiNoise3D_float(p, 2, 1, 1, grad, cell);
+    
+    
+    float3 v = cell * .8;// * (grad + distort * .1);
+    v += smoothstep(.05, .02, grad) * smoothstep(.4, .7, n0) * 2;
+    float3 c = Color * lerp(.9, 1, v);
+    
     // Output
 
-    Output = 1;
-    if (Step > 0 ) Output *= Color;
-    if (Step > 1 ) Output *= grainAtten;
-    if (Step > 2 ) Output *= dirtAtten;
-    if (Step > 3 ) Output *= shadowAtten;
+    //Output = 1;
+    //if (Step > 0 ) Output *= Color;
+    //if (Step > 1 ) Output *= grainAtten;
+    //if (Step > 2 ) Output *= dirtAtten;
+    //if (Step > 3 ) Output *= shadowAtten;
     //if (Step > 4 ) Output = lerp(Output, Output * .1, stripes * .8);
     
+    Output = c;
+    
     //Output = PerlinColor3D(PositionWS, 5);
     //Output = smoothstep(.97, .93, ao);
 }