Shading: Extend Noise node to other dimenstions.

This patch extends perlin noise to operate in 1D, 2D, 3D, and 4D
space. The noise code has also been refactored to be more readable.

The Color output and distortion patterns changed, so this patch
breaks backward compatibility. This is due to the fact that we
now use random offsets as noise seeds, as opposed to swizzling
and constants offsets.

Reviewers: brecht, JacquesLucke

Differential Revision: https://developer.blender.org/D5560

1 files changed, 153 insertions, 25 deletions

diff --git a/intern/cycles/kernel/svm/svm_noisetex.h b/intern/cycles/kernel/svm/svm_noisetex.h
index 91dc11691e6..c5a1e43a729 100644
--- a/intern/cycles/kernel/svm/svm_noisetex.h
+++ b/intern/cycles/kernel/svm/svm_noisetex.h
@@ -16,44 +16,172 @@
 
 CCL_NAMESPACE_BEGIN
 
-/* Noise */
+/* The following offset functions generate random offsets to be added to texture
+ * coordinates to act as a seed since the noise functions don't have seed values.
+ * A seed value is needed for generating distortion textures and color outputs.
+ * The offset's components are in the range [100, 200], not too high to cause
+ * bad precision and not to small to be noticeable. We use float seed because
+ * OSL only support float hashes.
+ */
+
+ccl_device_inline float random_float_offset(float seed)
+{
+  return 100.0f + hash_float_to_float(seed) * 100.0f;
+}
+
+ccl_device_inline float2 random_float2_offset(float seed)
+{
+  return make_float2(100.0f + hash_float2_to_float(make_float2(seed, 0.0f)) * 100.0f,
+                     100.0f + hash_float2_to_float(make_float2(seed, 1.0f)) * 100.0f);
+}
 
-ccl_device void svm_node_tex_noise(
-    KernelGlobals *kg, ShaderData *sd, float *stack, uint4 node, int *offset)
+ccl_device_inline float3 random_float3_offset(float seed)
 {
-  uint co_offset, scale_offset, detail_offset, distortion_offset, fac_offset, color_offset;
+  return make_float3(100.0f + hash_float2_to_float(make_float2(seed, 0.0f)) * 100.0f,
+                     100.0f + hash_float2_to_float(make_float2(seed, 1.0f)) * 100.0f,
+                     100.0f + hash_float2_to_float(make_float2(seed, 2.0f)) * 100.0f);
+}
 
-  svm_unpack_node_uchar4(node.y, &co_offset, &scale_offset, &detail_offset, &distortion_offset);
-  svm_unpack_node_uchar2(node.z, &color_offset, &fac_offset);
+ccl_device_inline float4 random_float4_offset(float seed)
+{
+  return make_float4(100.0f + hash_float2_to_float(make_float2(seed, 0.0f)) * 100.0f,
+                     100.0f + hash_float2_to_float(make_float2(seed, 1.0f)) * 100.0f,
+                     100.0f + hash_float2_to_float(make_float2(seed, 2.0f)) * 100.0f,
+                     100.0f + hash_float2_to_float(make_float2(seed, 3.0f)) * 100.0f);
+}
 
-  uint4 node2 = read_node(kg, offset);
+ccl_device void noise_texture_1d(
+    float co, float detail, float distortion, bool color_is_needed, float *value, float3 *color)
+{
+  float p = co;
+  if (distortion != 0.0f) {
+    p += noise_1d(p + random_float_offset(0.0f)) * distortion;
+  }
+
+  *value = fractal_noise_1d(p, detail);
+  if (color_is_needed) {
+    *color = make_float3(*value,
+                         fractal_noise_1d(p + random_float_offset(1.0f), detail),
+                         fractal_noise_1d(p + random_float_offset(2.0f), detail));
+  }
+}
+
+ccl_device void noise_texture_2d(
+    float2 co, float detail, float distortion, bool color_is_needed, float *value, float3 *color)
+{
+  float2 p = co;
+  if (distortion != 0.0f) {
+    p += make_float2(noise_2d(p + random_float2_offset(0.0f)) * distortion,
+                     noise_2d(p + random_float2_offset(1.0f)) * distortion);
+  }
 
-  float scale = stack_load_float_default(stack, scale_offset, node2.x);
-  float detail = stack_load_float_default(stack, detail_offset, node2.y);
-  float distortion = stack_load_float_default(stack, distortion_offset, node2.z);
-  float3 p = stack_load_float3(stack, co_offset) * scale;
-  int hard = 0;
+  *value = fractal_noise_2d(p, detail);
+  if (color_is_needed) {
+    *color = make_float3(*value,
+                         fractal_noise_2d(p + random_float2_offset(2.0f), detail),
+                         fractal_noise_2d(p + random_float2_offset(3.0f), detail));
+  }
+}
 
+ccl_device void noise_texture_3d(
+    float3 co, float detail, float distortion, bool color_is_needed, float *value, float3 *color)
+{
+  float3 p = co;
   if (distortion != 0.0f) {
-    float3 r, offset = make_float3(13.5f, 13.5f, 13.5f);
+    p += make_float3(noise_3d(p + random_float3_offset(0.0f)) * distortion,
+                     noise_3d(p + random_float3_offset(1.0f)) * distortion,
+                     noise_3d(p + random_float3_offset(2.0f)) * distortion);
+  }
 
-    r.x = noise(p + offset) * distortion;
-    r.y = noise(p) * distortion;
-    r.z = noise(p - offset) * distortion;
+  *value = fractal_noise_3d(p, detail);
+  if (color_is_needed) {
+    *color = make_float3(*value,
+                         fractal_noise_3d(p + random_float3_offset(3.0f), detail),
+                         fractal_noise_3d(p + random_float3_offset(4.0f), detail));
+  }
+}
 
-    p += r;
+ccl_device void noise_texture_4d(
+    float4 co, float detail, float distortion, bool color_is_needed, float *value, float3 *color)
+{
+  float4 p = co;
+  if (distortion != 0.0f) {
+    p += make_float4(noise_4d(p + random_float4_offset(0.0f)) * distortion,
+                     noise_4d(p + random_float4_offset(1.0f)) * distortion,
+                     noise_4d(p + random_float4_offset(2.0f)) * distortion,
+                     noise_4d(p + random_float4_offset(3.0f)) * distortion);
   }
 
-  float f = noise_turbulence(p, detail, hard);
+  *value = fractal_noise_4d(p, detail);
+  if (color_is_needed) {
+    *color = make_float3(*value,
+                         fractal_noise_4d(p + random_float4_offset(4.0f), detail),
+                         fractal_noise_4d(p + random_float4_offset(5.0f), detail));
+  }
+}
+
+ccl_device void svm_node_tex_noise(KernelGlobals *kg,
+                                   ShaderData *sd,
+                                   float *stack,
+                                   uint dimensions,
+                                   uint offsets1,
+                                   uint offsets2,
+                                   int *offset)
+{
+  uint vector_stack_offset, w_stack_offset, scale_stack_offset, detail_stack_offset;
+  uint distortion_stack_offset, value_stack_offset, color_stack_offset;
+
+  svm_unpack_node_uchar4(
+      offsets1, &vector_stack_offset, &w_stack_offset, &scale_stack_offset, &detail_stack_offset);
+  svm_unpack_node_uchar3(
+      offsets2, &distortion_stack_offset, &value_stack_offset, &color_stack_offset);
+
+  uint4 defaults = read_node(kg, offset);
+
+  float3 vector = stack_load_float3(stack, vector_stack_offset);
+  float w = stack_load_float_default(stack, w_stack_offset, defaults.x);
+  float scale = stack_load_float_default(stack, scale_stack_offset, defaults.y);
+  float detail = stack_load_float_default(stack, detail_stack_offset, defaults.z);
+  float distortion = stack_load_float_default(stack, distortion_stack_offset, defaults.w);
+
+  vector *= scale;
+  w *= scale;
+
+  float value;
+  float3 color;
+  switch (dimensions) {
+    case 1:
+      noise_texture_1d(w, detail, distortion, stack_valid(color_stack_offset), &value, &color);
+      break;
+    case 2:
+      noise_texture_2d(make_float2(vector.x, vector.y),
+                       detail,
+                       distortion,
+                       stack_valid(color_stack_offset),
+                       &value,
+                       &color);
+      break;
+    case 3:
+      noise_texture_3d(
+          vector, detail, distortion, stack_valid(color_stack_offset), &value, &color);
+      break;
+    case 4:
+      noise_texture_4d(make_float4(vector.x, vector.y, vector.z, w),
+                       detail,
+                       distortion,
+                       stack_valid(color_stack_offset),
+                       &value,
+                       &color);
+      break;
+    default:
+      kernel_assert(0);
+  }
 
-  if (stack_valid(fac_offset)) {
-    stack_store_float(stack, fac_offset, f);
+  if (stack_valid(value_stack_offset)) {
+    stack_store_float(stack, value_stack_offset, value);
   }
-  if (stack_valid(color_offset)) {
-    float3 color = make_float3(f,
-                               noise_turbulence(make_float3(p.y, p.x, p.z), detail, hard),
-                               noise_turbulence(make_float3(p.y, p.z, p.x), detail, hard));
-    stack_store_float3(stack, color_offset, color);
+  if (stack_valid(color_stack_offset)) {
+    stack_store_float3(stack, color_stack_offset, color);
   }
 }