Cycles: add new Spectrum and PackedSpectrum types

These replace float3 and packed_float3 in various places in the kernel where a
spectral color representation will be used in the future. That representation
will require more than 3 channels and conversion to from/RGB. The kernel code
was refactored to remove the assumption that Spectrum and RGB colors are the
same thing.

There are no functional changes, Spectrum is still a float3 and the conversion
functions are no-ops.

Differential Revision: https://developer.blender.org/D15535

1 files changed, 14 insertions, 14 deletions

diff --git a/intern/cycles/util/math.h b/intern/cycles/util/math.h
index f6400cb879f..0585dcc8ad5 100644
--- a/intern/cycles/util/math.h
+++ b/intern/cycles/util/math.h
@@ -595,26 +595,26 @@ ccl_device_inline void make_orthonormals(const float3 N,
 
 /* Color division */
 
-ccl_device_inline float3 safe_invert_color(float3 a)
+ccl_device_inline Spectrum safe_invert_color(Spectrum a)
 {
-  float x, y, z;
-
-  x = (a.x != 0.0f) ? 1.0f / a.x : 0.0f;
-  y = (a.y != 0.0f) ? 1.0f / a.y : 0.0f;
-  z = (a.z != 0.0f) ? 1.0f / a.z : 0.0f;
+  FOREACH_SPECTRUM_CHANNEL (i) {
+    GET_SPECTRUM_CHANNEL(a, i) = (GET_SPECTRUM_CHANNEL(a, i) != 0.0f) ?
+                                     1.0f / GET_SPECTRUM_CHANNEL(a, i) :
+                                     0.0f;
+  }
 
-  return make_float3(x, y, z);
+  return a;
 }
 
-ccl_device_inline float3 safe_divide_color(float3 a, float3 b)
+ccl_device_inline Spectrum safe_divide_color(Spectrum a, Spectrum b)
 {
-  float x, y, z;
-
-  x = (b.x != 0.0f) ? a.x / b.x : 0.0f;
-  y = (b.y != 0.0f) ? a.y / b.y : 0.0f;
-  z = (b.z != 0.0f) ? a.z / b.z : 0.0f;
+  FOREACH_SPECTRUM_CHANNEL (i) {
+    GET_SPECTRUM_CHANNEL(a, i) = (GET_SPECTRUM_CHANNEL(b, i) != 0.0f) ?
+                                     GET_SPECTRUM_CHANNEL(a, i) / GET_SPECTRUM_CHANNEL(b, i) :
+                                     0.0f;
+  }
 
-  return make_float3(x, y, z);
+  return a;
 }
 
 ccl_device_inline float3 safe_divide_even_color(float3 a, float3 b)