Enhance Worley noise with solid cells option (#2119)

Adds a new control to `worley2d` and `worley3d`, which allows artists to choose between a distance for each cell (the default) and solid values for each cell. This allows for more patterns to be expressed in materials (i.e. flakes).

documents/Specification/MaterialX.Specification.md

@@ -888,12 +888,14 @@ Standard Noise nodes:
 
 * **`worleynoise2d`**: 2D Worley noise using centered jitter, outputting float (distance metric to closest feature), vector2 (distance metrics to closest 2 features) or vector3 (distance metrics to closest 3 features).
     * `jitter` (float): amount to jitter the cell center position, with smaller values creating a more regular pattern.  Default is 1.0.
+    * `style` (integer): the output style, one of "distance" (distance to the cell center), or "solid" (constant value for each cell).
     * `texcoord` (vector2): the 2D position at which the noise is evaluated.  Default is to use the first set of texture coordinates.
 
 <a id="node-worleynoise3d"> </a>
 
 * **`worleynoise3d`**: 3D Worley noise using centered jitter, outputting float (distance metric to closest feature), vector2 (distance metrics to closest 2 features) or vector3 (distance metrics to closest 3 features).
     * `jitter` (float): amount to jitter the cell center position, with smaller values creating a more regular pattern.  Default is 1.0.
+    * `style` (integer): the output style, one of "distance" (distance to the cell center), or "solid" (constant value for each cell). Default is "distance".
     * `position` (vector3): the 3D position at which the noise is evaluated.  Default is to use the current 3D object-space coordinate.
 
 <a id="node-unifiednoise2d"> </a>

libraries/stdlib/genglsl/lib/mx_noise.glsl

@@ -437,16 +437,32 @@ vec4 mx_fractal_noise_vec4(vec3 p, int octaves, float lacunarity, float diminish
     return vec4(c, f);
 }
 
-float mx_worley_distance(vec2 p, int x, int y, int xoff, int yoff, float jitter, int metric)
+vec2 mx_worley_cell_position(int x, int y, int xoff, int yoff, float jitter)
 {
     vec3  tmp = mx_cell_noise_vec3(vec2(x+xoff, y+yoff));
     vec2  off = vec2(tmp.x, tmp.y);
 
     off -= 0.5f;
     off *= jitter;
     off += 0.5f;
+
+    return vec2(float(x), float(y)) + off;
+}
+
+vec3 mx_worley_cell_position(int x, int y, int z, int xoff, int yoff, int zoff, float jitter)
+{
+    vec3  off = mx_cell_noise_vec3(vec3(x+xoff, y+yoff, z+zoff));
+
+    off -= 0.5f;
+    off *= jitter;
+    off += 0.5f;
+
+    return vec3(float(x), float(y), float(z)) + off;
+}
 
-    vec2 cellpos = vec2(float(x), float(y)) + off;
+float mx_worley_distance(vec2 p, int x, int y, int xoff, int yoff, float jitter, int metric)
+{
+    vec2 cellpos = mx_worley_cell_position(x, y, xoff, yoff, jitter);
     vec2 diff = cellpos - p;
     if (metric == 2)
         return abs(diff.x) + abs(diff.y);       // Manhattan distance
@@ -458,13 +474,7 @@ float mx_worley_distance(vec2 p, int x, int y, int xoff, int yoff, float jitter,
 
 float mx_worley_distance(vec3 p, int x, int y, int z, int xoff, int yoff, int zoff, float jitter, int metric)
 {
-    vec3  off = mx_cell_noise_vec3(vec3(x+xoff, y+yoff, z+zoff));
-
-    off -= 0.5f;
-    off *= jitter;
-    off += 0.5f;
-
-    vec3 cellpos = vec3(float(x), float(y), float(z)) + off;
+    vec3 cellpos = mx_worley_cell_position(x, y, z, xoff, yoff, zoff, jitter);
     vec3 diff = cellpos - p;
     if (metric == 2)
         return abs(diff.x) + abs(diff.y) + abs(diff.z); // Manhattan distance
@@ -474,65 +484,91 @@ float mx_worley_distance(vec3 p, int x, int y, int z, int xoff, int yoff, int zo
     return dot(diff, diff);
 }
 
-float mx_worley_noise_float(vec2 p, float jitter, int metric)
+float mx_worley_noise_float(vec2 p, float jitter, int style, int metric)
 {
     int X, Y;
+    float dist;
     vec2 localpos = vec2(mx_floorfrac(p.x, X), mx_floorfrac(p.y, Y));
     float sqdist = 1e6f;        // Some big number for jitter > 1 (not all GPUs may be IEEE)
+    vec2 minpos = vec2(0,0);
     for (int x = -1; x <= 1; ++x)
     {
         for (int y = -1; y <= 1; ++y)
         {
             float dist = mx_worley_distance(localpos, x, y, X, Y, jitter, metric);
-            sqdist = min(sqdist, dist);
+            vec2 cellpos = mx_worley_cell_position(x, y, X, Y, jitter) - localpos;
+            if(dist < sqdist)
+            {
+                sqdist = dist;
+                minpos = cellpos;
+            }
         }
     }
-    if (metric == 0)
-        sqdist = sqrt(sqdist);
-    return sqdist;
+    if (style == 1)
+        return mx_cell_noise_float(minpos + p);
+    else
+    {
+        if (metric == 0)
+            sqdist = sqrt(sqdist);
+        return sqdist;
+    }
 }
 
-vec2 mx_worley_noise_vec2(vec2 p, float jitter, int metric)
+vec2 mx_worley_noise_vec2(vec2 p, float jitter, int style, int metric)
 {
     int X, Y;
     vec2 localpos = vec2(mx_floorfrac(p.x, X), mx_floorfrac(p.y, Y));
     vec2 sqdist = vec2(1e6f, 1e6f);
+    vec2 minpos = vec2(0,0);
     for (int x = -1; x <= 1; ++x)
     {
         for (int y = -1; y <= 1; ++y)
         {
             float dist = mx_worley_distance(localpos, x, y, X, Y, jitter, metric);
+            vec2 cellpos = mx_worley_cell_position(x, y, X, Y, jitter) - localpos;
             if (dist < sqdist.x)
             {
                 sqdist.y = sqdist.x;
                 sqdist.x = dist;
+                minpos = cellpos;
             }
             else if (dist < sqdist.y)
             {
                 sqdist.y = dist;
             }
         }
     }
-    if (metric == 0)
-        sqdist = sqrt(sqdist);
-    return sqdist;
+    if (style == 1)
+    {
+        vec3 tmp = mx_cell_noise_vec3(minpos + p);
+        return vec2(tmp.x,tmp.y);
+    }
+    else
+    {
+        if (metric == 0)
+            sqdist = sqrt(sqdist);
+        return sqdist;
+    }
 }
 
-vec3 mx_worley_noise_vec3(vec2 p, float jitter, int metric)
+vec3 mx_worley_noise_vec3(vec2 p, float jitter, int style, int metric)
 {
     int X, Y;
     vec2 localpos = vec2(mx_floorfrac(p.x, X), mx_floorfrac(p.y, Y));
     vec3 sqdist = vec3(1e6f, 1e6f, 1e6f);
+    vec2 minpos = vec2(0,0);
     for (int x = -1; x <= 1; ++x)
     {
         for (int y = -1; y <= 1; ++y)
         {
             float dist = mx_worley_distance(localpos, x, y, X, Y, jitter, metric);
+            vec2 cellpos = mx_worley_cell_position(x, y, X, Y, jitter) - localpos;
             if (dist < sqdist.x)
             {
                 sqdist.z = sqdist.y;
                 sqdist.y = sqdist.x;
                 sqdist.x = dist;
+                minpos = cellpos;
             }
             else if (dist < sqdist.y)
             {
@@ -545,48 +581,67 @@ vec3 mx_worley_noise_vec3(vec2 p, float jitter, int metric)
             }
         }
     }
-    if (metric == 0)
-        sqdist = sqrt(sqdist);
-    return sqdist;
+    if (style == 1)
+        return mx_cell_noise_vec3(minpos + p);
+    else
+    {
+        if (metric == 0)
+            sqdist = sqrt(sqdist);
+        return sqdist;
+    }
 }
 
-float mx_worley_noise_float(vec3 p, float jitter, int metric)
+float mx_worley_noise_float(vec3 p, float jitter, int style, int metric)
 {
     int X, Y, Z;
     vec3 localpos = vec3(mx_floorfrac(p.x, X), mx_floorfrac(p.y, Y), mx_floorfrac(p.z, Z));
     float sqdist = 1e6f;
+    vec3 minpos = vec3(0,0,0);
     for (int x = -1; x <= 1; ++x)
     {
         for (int y = -1; y <= 1; ++y)
         {
             for (int z = -1; z <= 1; ++z)
             {
                 float dist = mx_worley_distance(localpos, x, y, z, X, Y, Z, jitter, metric);
-                sqdist = min(sqdist, dist);
+                vec3 cellpos = mx_worley_cell_position(x, y, z, X, Y, Z, jitter) - localpos;
+                if(dist < sqdist)
+                {
+                    sqdist = dist;
+                    minpos = cellpos;
+                }
             }
         }
     }
-    if (metric == 0)
-        sqdist = sqrt(sqdist);
-    return sqdist;
+    if (style == 1)
+        return mx_cell_noise_float(minpos + p);
+    else
+    {
+        if (metric == 0)
+            sqdist = sqrt(sqdist);
+        return sqdist;
+    }
 }
 
-vec2 mx_worley_noise_vec2(vec3 p, float jitter, int metric)
+vec2 mx_worley_noise_vec2(vec3 p, float jitter, int style, int metric)
 {
     int X, Y, Z;
     vec3 localpos = vec3(mx_floorfrac(p.x, X), mx_floorfrac(p.y, Y), mx_floorfrac(p.z, Z));
     vec2 sqdist = vec2(1e6f, 1e6f);
+    vec3 minpos = vec3(0,0,0);
     for (int x = -1; x <= 1; ++x)
     {
         for (int y = -1; y <= 1; ++y)
         {
             for (int z = -1; z <= 1; ++z)
             {
                 float dist = mx_worley_distance(localpos, x, y, z, X, Y, Z, jitter, metric);
+                vec3 cellpos = mx_worley_cell_position(x, y, z, X, Y, Z, jitter) - localpos;
                 if (dist < sqdist.x)
                 {
                     sqdist.y = sqdist.x;
                     sqdist.x = dist;
+                    minpos = cellpos;
                 }
                 else if (dist < sqdist.y)
                 {
@@ -595,28 +650,39 @@ vec2 mx_worley_noise_vec2(vec3 p, float jitter, int metric)
             }
         }
     }
-    if (metric == 0)
-        sqdist = sqrt(sqdist);
-    return sqdist;
+    if (style == 1)
+    {
+        vec3 tmp = mx_cell_noise_vec3(minpos + p);
+        return vec2(tmp.x,tmp.y);
+    }
+    else
+    {
+        if (metric == 0)
+            sqdist = sqrt(sqdist);
+        return sqdist;
+    }
 }
 
-vec3 mx_worley_noise_vec3(vec3 p, float jitter, int metric)
+vec3 mx_worley_noise_vec3(vec3 p, float jitter, int style, int metric)
 {
     int X, Y, Z;
     vec3 localpos = vec3(mx_floorfrac(p.x, X), mx_floorfrac(p.y, Y), mx_floorfrac(p.z, Z));
     vec3 sqdist = vec3(1e6f, 1e6f, 1e6f);
+    vec3 minpos = vec3(0,0,0);
     for (int x = -1; x <= 1; ++x)
     {
         for (int y = -1; y <= 1; ++y)
         {
             for (int z = -1; z <= 1; ++z)
             {
                 float dist = mx_worley_distance(localpos, x, y, z, X, Y, Z, jitter, metric);
+                vec3 cellpos = mx_worley_cell_position(x, y, z, X, Y, Z, jitter) - localpos;
                 if (dist < sqdist.x)
                 {
                     sqdist.z = sqdist.y;
                     sqdist.y = sqdist.x;
                     sqdist.x = dist;
+                    minpos = cellpos;
                 }
                 else if (dist < sqdist.y)
                 {
@@ -630,7 +696,12 @@ vec3 mx_worley_noise_vec3(vec3 p, float jitter, int metric)
             }
         }
     }
-    if (metric == 0)
-        sqdist = sqrt(sqdist);
-    return sqdist;
+    if (style == 1)
+        return mx_cell_noise_vec3(minpos + p);
+    else
+    {
+        if (metric == 0)
+            sqdist = sqrt(sqdist);
+        return sqdist;
+    }
 }

libraries/stdlib/genglsl/mx_worleynoise2d_float.glsl

@@ -1,6 +1,6 @@
 #include "lib/mx_noise.glsl"
 
-void mx_worleynoise2d_float(vec2 texcoord, float jitter, out float result)
+void mx_worleynoise2d_float(vec2 texcoord, float jitter, int style, out float result)
 {
-    result = mx_worley_noise_float(texcoord, jitter, 0);
+    result = mx_worley_noise_float(texcoord, jitter, style, 0);
 }

libraries/stdlib/genglsl/mx_worleynoise2d_vector2.glsl

@@ -1,6 +1,6 @@
 #include "lib/mx_noise.glsl"
 
-void mx_worleynoise2d_vector2(vec2 texcoord, float jitter, out vec2 result)
+void mx_worleynoise2d_vector2(vec2 texcoord, float jitter, int style, out vec2 result)
 {
-    result = mx_worley_noise_vec2(texcoord, jitter, 0);
+    result = mx_worley_noise_vec2(texcoord, jitter, style, 0);
 }

libraries/stdlib/genglsl/mx_worleynoise2d_vector3.glsl

@@ -1,6 +1,6 @@
 #include "lib/mx_noise.glsl"
 
-void mx_worleynoise2d_vector3(vec2 texcoord, float jitter, out vec3 result)
+void mx_worleynoise2d_vector3(vec2 texcoord, float jitter, int style, out vec3 result)
 {
-    result = mx_worley_noise_vec3(texcoord, jitter, 0);
+    result = mx_worley_noise_vec3(texcoord, jitter, style, 0);
 }

libraries/stdlib/genglsl/mx_worleynoise3d_float.glsl

@@ -1,6 +1,6 @@
 #include "lib/mx_noise.glsl"
 
-void mx_worleynoise3d_float(vec3 position, float jitter, out float result)
+void mx_worleynoise3d_float(vec3 position, float jitter, int style, out float result)
 {
-    result = mx_worley_noise_float(position, jitter, 0);
+    result = mx_worley_noise_float(position, jitter, style, 0);
 }

libraries/stdlib/genglsl/mx_worleynoise3d_vector2.glsl

@@ -1,6 +1,6 @@
 #include "lib/mx_noise.glsl"
 
-void mx_worleynoise3d_vector2(vec3 position, float jitter, out vec2 result)
+void mx_worleynoise3d_vector2(vec3 position, float jitter, int style, out vec2 result)
 {
-    result = mx_worley_noise_vec2(position, jitter, 0);
+    result = mx_worley_noise_vec2(position, jitter, style, 0);
 }

libraries/stdlib/genglsl/mx_worleynoise3d_vector3.glsl

@@ -1,6 +1,6 @@
 #include "lib/mx_noise.glsl"
 
-void mx_worleynoise3d_vector3(vec3 position, float jitter, out vec3 result)
+void mx_worleynoise3d_vector3(vec3 position, float jitter, int style, out vec3 result)
 {
-    result = mx_worley_noise_vec3(position, jitter, 0);
+    result = mx_worley_noise_vec3(position, jitter, style, 0);
 }

libraries/stdlib/stdlib_defs.mtlx

@@ -1002,16 +1002,19 @@
   <nodedef name="ND_worleynoise2d_float" node="worleynoise2d" nodegroup="procedural2d">
     <input name="texcoord" type="vector2" defaultgeomprop="UV0" />
     <input name="jitter" type="float" value="1.0" />
+    <input name="style" uiname="Cell Style" type="integer" value="0" enum="Distance,Solid" enumvalues="0,1" />
     <output name="out" type="float" default="0.0" />
   </nodedef>
   <nodedef name="ND_worleynoise2d_vector2" node="worleynoise2d" nodegroup="procedural2d">
     <input name="texcoord" type="vector2" defaultgeomprop="UV0" />
     <input name="jitter" type="float" value="1.0" />
+    <input name="style" uiname="Cell Style" type="integer" value="0" enum="Distance,Solid" enumvalues="0,1" />
     <output name="out" type="vector2" default="0.0, 0.0" />
   </nodedef>
   <nodedef name="ND_worleynoise2d_vector3" node="worleynoise2d" nodegroup="procedural2d">
     <input name="texcoord" type="vector2" defaultgeomprop="UV0" />
     <input name="jitter" type="float" value="1.0" />
+    <input name="style" uiname="Cell Style" type="integer" value="0" enum="Distance,Solid" enumvalues="0,1" />
     <output name="out" type="vector3" default="0.0, 0.0, 0.0" />
   </nodedef>
 
@@ -1022,16 +1025,19 @@
   <nodedef name="ND_worleynoise3d_float" node="worleynoise3d" nodegroup="procedural3d">
     <input name="position" type="vector3" defaultgeomprop="Pobject" />
     <input name="jitter" type="float" value="1.0" />
+    <input name="style" uiname="Cell Style" type="integer" value="0" enum="Distance,Solid" enumvalues="0,1" />
     <output name="out" type="float" default="0.0" />
   </nodedef>
   <nodedef name="ND_worleynoise3d_vector2" node="worleynoise3d" nodegroup="procedural3d">
     <input name="position" type="vector3" defaultgeomprop="Pobject" />
     <input name="jitter" type="float" value="1.0" />
+    <input name="style" uiname="Cell Style" type="integer" value="0" enum="Distance,Solid" enumvalues="0,1" />
     <output name="out" type="vector2" default="0.0, 0.0" />
   </nodedef>
   <nodedef name="ND_worleynoise3d_vector3" node="worleynoise3d" nodegroup="procedural3d">
     <input name="position" type="vector3" defaultgeomprop="Pobject" />
     <input name="jitter" type="float" value="1.0" />
+    <input name="style" uiname="Cell Style" type="integer" value="0" enum="Distance,Solid" enumvalues="0,1" />
     <output name="out" type="vector3" default="0.0, 0.0, 0.0" />
   </nodedef>