Cycles / Wavelength to RGB node:

* Added a node to convert wavelength (in nanometers, from 380nm to 780nm) to RGB values. This can be useful to match real world colors easier.

* Code cleanup:
** Moved color functions (xyz and hsv) into dedicated utility files.
** Remove svm_lerp(), use interp() instead. 

Documentation:
http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Nodes/More#Wavelength

Example render:
http://www.pasteall.org/pic/show.php?id=53202

This is part of my GSoC 2013. (revisions 57322, 57326, 57335 and 57367 from soc-2013-dingto). 

1 files changed, 7 insertions, 14 deletions

diff --git a/intern/cycles/kernel/svm/svm_mix.h b/intern/cycles/kernel/svm/svm_mix.h
index 888e4d9645e..d6a306af64d 100644
--- a/intern/cycles/kernel/svm/svm_mix.h
+++ b/intern/cycles/kernel/svm/svm_mix.h
@@ -16,28 +16,21 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#include "svm_hsv.h"
-
 CCL_NAMESPACE_BEGIN
 
-__device float3 svm_lerp(const float3 a, const float3 b, float t)
-{
-	return (a * (1.0f - t) + b * t);
-}
-
 __device float3 svm_mix_blend(float t, float3 col1, float3 col2)
 {
-	return svm_lerp(col1, col2, t);
+	return interp(col1, col2, t);
 }
 
 __device float3 svm_mix_add(float t, float3 col1, float3 col2)
 {
-	return svm_lerp(col1, col1 + col2, t);
+	return interp(col1, col1 + col2, t);
 }
 
 __device float3 svm_mix_mul(float t, float3 col1, float3 col2)
 {
-	return svm_lerp(col1, col1 * col2, t);
+	return interp(col1, col1 * col2, t);
 }
 
 __device float3 svm_mix_screen(float t, float3 col1, float3 col2)
@@ -75,7 +68,7 @@ __device float3 svm_mix_overlay(float t, float3 col1, float3 col2)
 
 __device float3 svm_mix_sub(float t, float3 col1, float3 col2)
 {
-	return svm_lerp(col1, col1 - col2, t);
+	return interp(col1, col1 - col2, t);
 }
 
 __device float3 svm_mix_div(float t, float3 col1, float3 col2)
@@ -93,7 +86,7 @@ __device float3 svm_mix_div(float t, float3 col1, float3 col2)
 
 __device float3 svm_mix_diff(float t, float3 col1, float3 col2)
 {
-	return svm_lerp(col1, fabs(col1 - col2), t);
+	return interp(col1, fabs(col1 - col2), t);
 }
 
 __device float3 svm_mix_dark(float t, float3 col1, float3 col2)
@@ -191,7 +184,7 @@ __device float3 svm_mix_hue(float t, float3 col1, float3 col2)
 		hsv.x = hsv2.x;
 		float3 tmp = hsv_to_rgb(hsv); 
 
-		outcol = svm_lerp(outcol, tmp, t);
+		outcol = interp(outcol, tmp, t);
 	}
 
 	return outcol;
@@ -238,7 +231,7 @@ __device float3 svm_mix_color(float t, float3 col1, float3 col2)
 		hsv.y = hsv2.y;
 		float3 tmp = hsv_to_rgb(hsv); 
 
-		outcol = svm_lerp(outcol, tmp, t);
+		outcol = interp(outcol, tmp, t);
 	}
 
 	return outcol;