Cycles / Blackbody to RGB node:

* Added a node to convert a temperature in Kelvin to an RGB color. This can be used e.g. for lights, to easily find the right color temperature. 
= Some common temperatures =
Candle light: 1500 Kelvin
Sunset/Sunrise: 1850 Kelvin
Studio lamps: 3200 Kelvin
Horizon daylight: 5000 Kelvin

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

Thanks to Philipp Oeser (lichtwerk), who essentially contributed to this with a patch! :)

This is part of my GSoC 2013 project. SVN merge of r57424, r57487, r57507, r57525, r58253 and r58774

24 files changed, 437 insertions, 0 deletions

diff --git a/intern/cycles/blender/blender_shader.cpp b/intern/cycles/blender/blender_shader.cpp
index 923f9b1e726..ee6a0887d45 100644
--- a/intern/cycles/blender/blender_shader.cpp
+++ b/intern/cycles/blender/blender_shader.cpp
@@ -400,6 +400,9 @@ static ShaderNode *add_node(Scene *scene, BL::BlendData b_data, BL::Scene b_scen
 	else if (b_node.is_a(&RNA_ShaderNodeWavelength)) {
 		node = new WavelengthNode();
 	}
+	else if (b_node.is_a(&RNA_ShaderNodeBlackbody)) {
+		node = new BlackbodyNode();
+	}
 	else if (b_node.is_a(&RNA_ShaderNodeLightPath)) {
 		node = new LightPathNode();
 	}
diff --git a/intern/cycles/kernel/CMakeLists.txt b/intern/cycles/kernel/CMakeLists.txt
index 2fa1393e935..ac0b9895c78 100644
--- a/intern/cycles/kernel/CMakeLists.txt
+++ b/intern/cycles/kernel/CMakeLists.txt
@@ -72,6 +72,7 @@ set(SRC_CLOSURE_HEADERS
 set(SRC_SVM_HEADERS
 	svm/svm.h
 	svm/svm_attribute.h
+	svm/svm_blackbody.h
 	svm/svm_camera.h
 	svm/svm_closure.h
 	svm/svm_convert.h
diff --git a/intern/cycles/kernel/kernel_types.h b/intern/cycles/kernel/kernel_types.h
index 733eb665860..1010fdea627 100644
--- a/intern/cycles/kernel/kernel_types.h
+++ b/intern/cycles/kernel/kernel_types.h
@@ -44,6 +44,12 @@ CCL_NAMESPACE_BEGIN
 #define BSSRDF_MIN_RADIUS			1e-8f
 #define BSSRDF_MAX_ATTEMPTS			8
 
+#define BB_DRAPPER				800.0
+#define BB_MAX_TABLE_RANGE		12000.0
+#define BB_TABLE_XPOWER			1.5
+#define BB_TABLE_YPOWER			5.0
+#define BB_TABLE_SPACING		2.0
+
 #define TEX_NUM_FLOAT_IMAGES	5
 
 /* device capabilities */
@@ -810,6 +816,12 @@ typedef struct KernelBSSRDF {
 	int pad1, pad2;
 } KernelBSSRDF;
 
+typedef struct KernelBlackbody {
+	int table_offset;
+	int pad1, pad2, pad3;
+} KernelBLACKBODY;
+
+
 typedef struct KernelData {
 	KernelCamera cam;
 	KernelFilm film;
@@ -819,6 +831,7 @@ typedef struct KernelData {
 	KernelBVH bvh;
 	KernelCurves curve_kernel_data;
 	KernelBSSRDF bssrdf;
+	KernelBlackbody blackbody;
 } KernelData;
 
 CCL_NAMESPACE_END
diff --git a/intern/cycles/kernel/shaders/CMakeLists.txt b/intern/cycles/kernel/shaders/CMakeLists.txt
index 23112f56536..2df8140ebbd 100644
--- a/intern/cycles/kernel/shaders/CMakeLists.txt
+++ b/intern/cycles/kernel/shaders/CMakeLists.txt
@@ -68,6 +68,7 @@ set(SRC_OSL
 	node_voronoi_texture.osl
 	node_ward_bsdf.osl
 	node_wavelength.osl
+	node_blackbody.osl
 	node_wave_texture.osl
 	node_wireframe.osl
 )
diff --git a/intern/cycles/kernel/shaders/node_blackbody.osl b/intern/cycles/kernel/shaders/node_blackbody.osl
new file mode 100644
index 00000000000..3eb0ec4b5e3
--- /dev/null
+++ b/intern/cycles/kernel/shaders/node_blackbody.osl
@@ -0,0 +1,33 @@
+/*
+ * Copyright 2013, Blender Foundation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "stdosl.h"
+
+shader node_blackbody(
+	float Temperature = 1200.0,
+	output color Color = 0.0)
+{
+	color rgb = blackbody(Temperature);
+	
+	/* Scale by luminance */
+	float l = luminance(rgb);
+	if (l != 0.0)
+		rgb /= l;
+	Color = rgb;
+}
+
diff --git a/intern/cycles/kernel/svm/svm.h b/intern/cycles/kernel/svm/svm.h
index e5df880b596..0a8896f3c44 100644
--- a/intern/cycles/kernel/svm/svm.h
+++ b/intern/cycles/kernel/svm/svm.h
@@ -146,6 +146,7 @@ CCL_NAMESPACE_END
 
 #include "svm_attribute.h"
 #include "svm_gradient.h"
+#include "svm_blackbody.h"
 #include "svm_closure.h"
 #include "svm_noisetex.h"
 #include "svm_convert.h"
@@ -366,6 +367,9 @@ __device_noinline void svm_eval_nodes(KernelGlobals *kg, ShaderData *sd, ShaderT
 			case NODE_WAVELENGTH:
 				svm_node_wavelength(sd, stack, node.y, node.z);
 				break;
+			case NODE_BLACKBODY:
+				svm_node_blackbody(kg, sd, stack, node.y, node.z);
+				break;
 			case NODE_SET_DISPLACEMENT:
 				svm_node_set_displacement(sd, stack, node.y);
 				break;
diff --git a/intern/cycles/kernel/svm/svm_blackbody.h b/intern/cycles/kernel/svm/svm_blackbody.h
new file mode 100644
index 00000000000..3c6e11ca683
--- /dev/null
+++ b/intern/cycles/kernel/svm/svm_blackbody.h
@@ -0,0 +1,84 @@
+/*
+ * Adapted from Open Shading Language with this license:
+ *
+ * Copyright (c) 2009-2010 Sony Pictures Imageworks Inc., et al.
+ * All Rights Reserved.
+ *
+ * Modifications Copyright 2013, Blender Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * * Neither the name of Sony Pictures Imageworks nor the names of its
+ *   contributors may be used to endorse or promote products derived from
+ *   this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+CCL_NAMESPACE_BEGIN
+
+/* Blackbody Node */
+
+__device void svm_node_blackbody(KernelGlobals *kg, ShaderData *sd, float *stack, uint temperature_offset, uint col_offset)
+{
+	/* Output */
+	float3 color_rgb = make_float3(0.0f, 0.0f, 0.0f);
+
+	/* Input */
+	float temperature = stack_load_float(stack, temperature_offset);
+
+	if (temperature < BB_DRAPPER) {
+		/* just return very very dim red */
+		color_rgb = make_float3(1.0e-6f,0.0f,0.0f);
+	}
+	else if (temperature <= BB_MAX_TABLE_RANGE) {
+		/* This is the overall size of the table */
+		const int lookuptablesize = 956;
+		const float lookuptablenormalize = 1.0f/956.0f;
+
+		/* reconstruct a proper index for the table lookup, compared to OSL we don't look up two colors
+		just one (the OSL-lerp is also automatically done for us by "lookup_table_read") */
+		float t = powf((temperature - BB_DRAPPER) * (1.0f / BB_TABLE_SPACING), 1.0f/BB_TABLE_XPOWER);
+
+		int blackbody_table_offset = kernel_data.blackbody.table_offset;
+
+		/* Retrieve colors from the lookup table */
+		float lutval = t*lookuptablenormalize;
+		float R = lookup_table_read(kg, lutval, blackbody_table_offset, lookuptablesize);
+		lutval = (t + 319.0f*1.0f)*lookuptablenormalize;
+		float G = lookup_table_read(kg, lutval, blackbody_table_offset, lookuptablesize);
+		lutval = (t + 319.0f*2.0f)*lookuptablenormalize;
+		float B = lookup_table_read(kg, lutval, blackbody_table_offset, lookuptablesize);
+
+		R = powf(R, BB_TABLE_YPOWER);
+		G = powf(G, BB_TABLE_YPOWER);
+		B = powf(B, BB_TABLE_YPOWER);
+
+		color_rgb = make_float3(R, G, B);
+	}
+
+	/* Luminance */
+	float l = linear_rgb_to_gray(color_rgb);
+	if (l != 0.0f)
+		color_rgb /= l;
+
+	if (stack_valid(col_offset))
+		stack_store_float3(stack, col_offset, color_rgb);
+}
+
+CCL_NAMESPACE_END
diff --git a/intern/cycles/kernel/svm/svm_types.h b/intern/cycles/kernel/svm/svm_types.h
index 85719265292..1e096c7f76c 100644
--- a/intern/cycles/kernel/svm/svm_types.h
+++ b/intern/cycles/kernel/svm/svm_types.h
@@ -53,6 +53,7 @@ typedef enum NodeType {
 	NODE_FRESNEL,
 	NODE_WIREFRAME,
 	NODE_WAVELENGTH,
+	NODE_BLACKBODY,
 	NODE_EMISSION_WEIGHT,
 	NODE_TEX_GRADIENT,
 	NODE_TEX_VORONOI,
diff --git a/intern/cycles/render/CMakeLists.txt b/intern/cycles/render/CMakeLists.txt
index f3f230c29dc..0cf29435a8c 100644
--- a/intern/cycles/render/CMakeLists.txt
+++ b/intern/cycles/render/CMakeLists.txt
@@ -16,6 +16,7 @@ set(INC_SYS
 set(SRC
 	attribute.cpp
 	background.cpp
+	blackbody.cpp
 	buffers.cpp
 	bssrdf.cpp
 	camera.cpp
@@ -43,6 +44,7 @@ set(SRC
 set(SRC_HEADERS
 	attribute.h
 	background.h
+	blackbody.h
 	buffers.h
 	bssrdf.h
 	camera.h
diff --git a/intern/cycles/render/blackbody.cpp b/intern/cycles/render/blackbody.cpp
new file mode 100644
index 00000000000..467368935d7
--- /dev/null
+++ b/intern/cycles/render/blackbody.cpp
@@ -0,0 +1,140 @@
+/*
+ * Adapted from Open Shading Language with this license:
+ *
+ * Copyright (c) 2009-2010 Sony Pictures Imageworks Inc., et al.
+ * All Rights Reserved.
+ *
+ * Modifications Copyright 2013, Blender Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * * Neither the name of Sony Pictures Imageworks nor the names of its
+ *   contributors may be used to endorse or promote products derived from
+ *   this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "blackbody.h"
+#include "util_color.h"
+#include "util_math.h"
+
+#include "kernel_types.h"
+
+CCL_NAMESPACE_BEGIN
+
+vector<float> blackbody_table()
+{
+	/* quoted from OSLs opcolor.cpp
+	In order to speed up the blackbody computation, we have a table
+	storing the precomputed BB values for a range of temperatures.  Less
+	than BB_DRAPER always returns 0.  Greater than BB_MAX_TABLE_RANGE
+	does the full computation, we think it'll be rare to inquire higher
+	temperatures.
+
+	Since the bb function is so nonlinear, we actually space the table
+	entries nonlinearly, with the relationship between the table index i
+	and the temperature T as follows:
+	i = ((T-Draper)/spacing)^(1/xpower)
+	T = pow(i, xpower) * spacing + Draper
+	And furthermore, we store in the table the true value raised ^(1/5).
+	I tuned this a bit, and with the current values we can have all
+	blackbody results accurate to within 0.1% with a table size of 317
+	(about 5 KB of data).
+	*/
+
+	const float cie_colour_match[81][3] = {
+		{0.0014,0.0000,0.0065}, {0.0022,0.0001,0.0105}, {0.0042,0.0001,0.0201},
+		{0.0076,0.0002,0.0362}, {0.0143,0.0004,0.0679}, {0.0232,0.0006,0.1102},
+		{0.0435,0.0012,0.2074}, {0.0776,0.0022,0.3713}, {0.1344,0.0040,0.6456},
+		{0.2148,0.0073,1.0391}, {0.2839,0.0116,1.3856}, {0.3285,0.0168,1.6230},
+		{0.3483,0.0230,1.7471}, {0.3481,0.0298,1.7826}, {0.3362,0.0380,1.7721},
+		{0.3187,0.0480,1.7441}, {0.2908,0.0600,1.6692}, {0.2511,0.0739,1.5281},
+		{0.1954,0.0910,1.2876}, {0.1421,0.1126,1.0419}, {0.0956,0.1390,0.8130},
+		{0.0580,0.1693,0.6162}, {0.0320,0.2080,0.4652}, {0.0147,0.2586,0.3533},
+		{0.0049,0.3230,0.2720}, {0.0024,0.4073,0.2123}, {0.0093,0.5030,0.1582},
+		{0.0291,0.6082,0.1117}, {0.0633,0.7100,0.0782}, {0.1096,0.7932,0.0573},
+		{0.1655,0.8620,0.0422}, {0.2257,0.9149,0.0298}, {0.2904,0.9540,0.0203},
+		{0.3597,0.9803,0.0134}, {0.4334,0.9950,0.0087}, {0.5121,1.0000,0.0057},
+		{0.5945,0.9950,0.0039}, {0.6784,0.9786,0.0027}, {0.7621,0.9520,0.0021},
+		{0.8425,0.9154,0.0018}, {0.9163,0.8700,0.0017}, {0.9786,0.8163,0.0014},
+		{1.0263,0.7570,0.0011}, {1.0567,0.6949,0.0010}, {1.0622,0.6310,0.0008},
+		{1.0456,0.5668,0.0006}, {1.0026,0.5030,0.0003}, {0.9384,0.4412,0.0002},
+		{0.8544,0.3810,0.0002}, {0.7514,0.3210,0.0001}, {0.6424,0.2650,0.0000},
+		{0.5419,0.2170,0.0000}, {0.4479,0.1750,0.0000}, {0.3608,0.1382,0.0000},
+		{0.2835,0.1070,0.0000}, {0.2187,0.0816,0.0000}, {0.1649,0.0610,0.0000},
+		{0.1212,0.0446,0.0000}, {0.0874,0.0320,0.0000}, {0.0636,0.0232,0.0000},
+		{0.0468,0.0170,0.0000}, {0.0329,0.0119,0.0000}, {0.0227,0.0082,0.0000},
+		{0.0158,0.0057,0.0000}, {0.0114,0.0041,0.0000}, {0.0081,0.0029,0.0000},
+		{0.0058,0.0021,0.0000}, {0.0041,0.0015,0.0000}, {0.0029,0.0010,0.0000},
+		{0.0020,0.0007,0.0000}, {0.0014,0.0005,0.0000}, {0.0010,0.0004,0.0000},
+		{0.0007,0.0002,0.0000}, {0.0005,0.0002,0.0000}, {0.0003,0.0001,0.0000},
+		{0.0002,0.0001,0.0000}, {0.0002,0.0001,0.0000}, {0.0001,0.0000,0.0000},
+		{0.0001,0.0000,0.0000}, {0.0001,0.0000,0.0000}, {0.0000,0.0000,0.0000}
+	};
+
+	const double c1 = 3.74183e-16; // 2*pi*h*c^2, W*m^2
+	const double c2 = 1.4388e-2;   // h*c/k, m*K
+								   // h is Planck's const, k is Boltzmann's
+	const float dlambda = 5.0f * 1e-9;  // in meters
+
+	/* Blackbody table from 800 to 12k Kelvin (319 entries (317+2 offset) * 3) */
+	vector<float> blackbody_table(956);
+
+	float X, Y, Z;
+
+	/* ToDo: bring this back to what OSL does with the lastTemperature limit ? */
+	for (int i = 0;  i <= 317;  ++i) {
+		float Temperature = powf (float(i), BB_TABLE_XPOWER) * BB_TABLE_SPACING + BB_DRAPPER;
+		X = 0;
+		Y = 0;
+		Z = 0;
+
+		/* from OSL "spectrum_to_XYZ" */
+		for (int n = 0; n < 81; ++n) {
+			float lambda = 380.0f + 5.0f * n;
+			double wlm = lambda * 1e-9;   // Wavelength in meters
+			// N.B. spec_intens returns result in W/m^2 but it's a differential,
+			// needs to be scaled by dlambda!
+			float spec_intens = float((c1 * powf(wlm,-5.0)) / (expf(c2 / (wlm * Temperature)) -1.0f));
+			float Me = spec_intens * dlambda;
+
+			X += Me * cie_colour_match[n][0];
+			Y += Me * cie_colour_match[n][1];
+			Z += Me * cie_colour_match[n][2];
+		}
+		
+		/* Convert from xyz color space */
+		float3 col = xyz_to_rgb(X, Y, Z);
+
+		/* Clamp to zero if values are smaller */
+		col = max(col, make_float3(0.0f, 0.0f, 0.0f));
+
+		col.x = powf(col.x, 1.0f / BB_TABLE_YPOWER);
+		col.y = powf(col.y, 1.0f / BB_TABLE_YPOWER);
+		col.z = powf(col.z, 1.0f / BB_TABLE_YPOWER);
+
+		/* Store in table in RRRGGGBBB format */
+		blackbody_table[i] = col.x;
+		blackbody_table[i+319*1] = col.y;
+		blackbody_table[i+319*2] = col.z;	
+	}
+
+	return blackbody_table;
+}
+CCL_NAMESPACE_END
diff --git a/intern/cycles/render/blackbody.h b/intern/cycles/render/blackbody.h
new file mode 100644
index 00000000000..a177238f689
--- /dev/null
+++ b/intern/cycles/render/blackbody.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright 2011, Blender Foundation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __BLACKBODY_H__
+#define __BLACKBODY_H__
+
+#include "util_vector.h"
+
+CCL_NAMESPACE_BEGIN
+
+vector<float> blackbody_table();
+
+CCL_NAMESPACE_END
+
+#endif /* __BLACKBODY_H__ */
diff --git a/intern/cycles/render/graph.h b/intern/cycles/render/graph.h
index 90e4760ba1c..da8ed987346 100644
--- a/intern/cycles/render/graph.h
+++ b/intern/cycles/render/graph.h
@@ -189,6 +189,7 @@ public:
 	virtual bool has_surface_emission() { return false; }
 	virtual bool has_surface_transparent() { return false; }
 	virtual bool has_surface_bssrdf() { return false; }
+	virtual bool has_converter_blackbody() { return false; }
 
 	vector<ShaderInput*> inputs;
 	vector<ShaderOutput*> outputs;
diff --git a/intern/cycles/render/nodes.cpp b/intern/cycles/render/nodes.cpp
index bd254c8e0d1..9349e7b90ae 100644
--- a/intern/cycles/render/nodes.cpp
+++ b/intern/cycles/render/nodes.cpp
@@ -2993,6 +2993,30 @@ void WavelengthNode::compile(OSLCompiler& compiler)
 	compiler.add(this, "node_wavelength");
 }
 
+/* Blackbody */
+
+BlackbodyNode::BlackbodyNode()
+: ShaderNode("Blackbody")
+{
+	add_input("Temperature", SHADER_SOCKET_FLOAT, 1200.0f);
+	add_output("Color", SHADER_SOCKET_COLOR);
+}
+
+void BlackbodyNode::compile(SVMCompiler& compiler)
+{
+	ShaderInput *temperature_in = input("Temperature");
+	ShaderOutput *color_out = output("Color");
+
+	compiler.stack_assign(temperature_in);
+	compiler.stack_assign(color_out);
+	compiler.add_node(NODE_BLACKBODY, temperature_in->stack_offset, color_out->stack_offset);
+}
+
+void BlackbodyNode::compile(OSLCompiler& compiler)
+{
+	compiler.add(this, "node_blackbody");
+}
+
 /* Output */
 
 OutputNode::OutputNode()
diff --git a/intern/cycles/render/nodes.h b/intern/cycles/render/nodes.h
index 78920d589ed..532ff41abee 100644
--- a/intern/cycles/render/nodes.h
+++ b/intern/cycles/render/nodes.h
@@ -462,6 +462,13 @@ public:
 	SHADER_NODE_CLASS(WavelengthNode)
 };
 
+class BlackbodyNode : public ShaderNode {
+public:
+	SHADER_NODE_CLASS(BlackbodyNode)
+	
+	bool has_converter_blackbody() { return true; }
+};
+
 class MathNode : public ShaderNode {
 public:
 	SHADER_NODE_CLASS(MathNode)
diff --git a/intern/cycles/render/shader.cpp b/intern/cycles/render/shader.cpp
index 21b43380f2c..5b326e0a017 100644
--- a/intern/cycles/render/shader.cpp
+++ b/intern/cycles/render/shader.cpp
@@ -18,6 +18,7 @@
 
 #include "background.h"
 #include "bssrdf.h"
+#include "blackbody.h"
 #include "device.h"
 #include "graph.h"
 #include "light.h"
@@ -51,6 +52,7 @@ Shader::Shader()
 	has_surface_transparent = false;
 	has_surface_emission = false;
 	has_surface_bssrdf = false;
+	has_converter_blackbody = false;
 	has_volume = false;
 	has_displacement = false;
 
@@ -127,6 +129,7 @@ ShaderManager::ShaderManager()
 {
 	need_update = true;
 	bssrdf_table_offset = TABLE_OFFSET_INVALID;
+	blackbody_table_offset = TABLE_OFFSET_INVALID;
 }
 
 ShaderManager::~ShaderManager()
@@ -218,6 +221,7 @@ void ShaderManager::device_update_common(Device *device, DeviceScene *dscene, Sc
 	uint *shader_flag = dscene->shader_flag.resize(shader_flag_size);
 	uint i = 0;
 	bool has_surface_bssrdf = false;
+	bool has_converter_blackbody = false;
 
 	foreach(Shader *shader, scene->shaders) {
 		uint flag = 0;
@@ -232,6 +236,8 @@ void ShaderManager::device_update_common(Device *device, DeviceScene *dscene, Sc
 			flag |= SD_HOMOGENEOUS_VOLUME;
 		if(shader->has_surface_bssrdf)
 			has_surface_bssrdf = true;
+		if(shader->has_converter_blackbody)
+			has_converter_blackbody = true;
 
 		shader_flag[i++] = flag;
 		shader_flag[i++] = shader->pass_id;
@@ -257,6 +263,21 @@ void ShaderManager::device_update_common(Device *device, DeviceScene *dscene, Sc
 		scene->lookup_tables->remove_table(bssrdf_table_offset);
 		bssrdf_table_offset = TABLE_OFFSET_INVALID;
 	}
+
+	/* blackbody lookup table */
+	KernelBlackbody *kblackbody = &dscene->data.blackbody;
+	
+	if(has_converter_blackbody && blackbody_table_offset == TABLE_OFFSET_INVALID) {
+		vector<float> table = blackbody_table();
+		blackbody_table_offset = scene->lookup_tables->add_table(dscene, table);
+		
+		kblackbody->table_offset = (int)blackbody_table_offset;
+	}
+	else if(!has_converter_blackbody && blackbody_table_offset != TABLE_OFFSET_INVALID) {
+		scene->lookup_tables->remove_table(blackbody_table_offset);
+		blackbody_table_offset = TABLE_OFFSET_INVALID;
+	}
+
 }
 
 void ShaderManager::device_free_common(Device *device, DeviceScene *dscene, Scene *scene)
@@ -266,6 +287,11 @@ void ShaderManager::device_free_common(Device *device, DeviceScene *dscene, Scen
 		bssrdf_table_offset = TABLE_OFFSET_INVALID;
 	}
 
+	if(blackbody_table_offset != TABLE_OFFSET_INVALID) {
+		scene->lookup_tables->remove_table(blackbody_table_offset);
+		blackbody_table_offset = TABLE_OFFSET_INVALID;
+	}
+
 	device->tex_free(dscene->shader_flag);
 	dscene->shader_flag.clear();
 }
diff --git a/intern/cycles/render/shader.h b/intern/cycles/render/shader.h
index 8810017068b..d7eac603fa6 100644
--- a/intern/cycles/render/shader.h
+++ b/intern/cycles/render/shader.h
@@ -77,6 +77,7 @@ public:
 	bool has_volume;
 	bool has_displacement;
 	bool has_surface_bssrdf;
+	bool has_converter_blackbody;
 
 	/* requested mesh attributes */
 	AttributeRequestSet attributes;
@@ -142,6 +143,7 @@ protected:
 	AttributeIDMap unique_attribute_id;
 
 	size_t bssrdf_table_offset;
+	size_t blackbody_table_offset;
 };
 
 CCL_NAMESPACE_END
diff --git a/intern/cycles/render/svm.cpp b/intern/cycles/render/svm.cpp
index 3e211a3ee24..9e887aeadf2 100644
--- a/intern/cycles/render/svm.cpp
+++ b/intern/cycles/render/svm.cpp
@@ -398,6 +398,10 @@ void SVMCompiler::generate_svm_nodes(const set<ShaderNode*>& nodes, set<ShaderNo
 							inputs_done = false;
 
 				if(inputs_done) {
+					/* Detect if we have a blackbody converter, to prepare lookup table */
+					if(node->has_converter_blackbody())
+					current_shader->has_converter_blackbody = true;
+
 					node->compile(*this);
 					stack_clear_users(node, done);
 					stack_clear_temporary(node);
@@ -672,6 +676,7 @@ void SVMCompiler::compile(Shader *shader, vector<int4>& global_svm_nodes, int in
 	shader->has_surface_emission = false;
 	shader->has_surface_transparent = false;
 	shader->has_surface_bssrdf = false;
+	shader->has_converter_blackbody = false;
 	shader->has_volume = false;
 	shader->has_displacement = false;
 
diff --git a/release/scripts/startup/nodeitems_builtins.py b/release/scripts/startup/nodeitems_builtins.py
index af966fa106e..f4bfc9b0cec 100644
--- a/release/scripts/startup/nodeitems_builtins.py
+++ b/release/scripts/startup/nodeitems_builtins.py
@@ -227,6 +227,7 @@ shader_node_categories = [
         NodeItem("ShaderNodeSeparateRGB"),
         NodeItem("ShaderNodeCombineRGB"),
         NodeItem("ShaderNodeWavelength"),
+        NodeItem("ShaderNodeBlackbody"),
         ]),
     ShaderNewNodeCategory("SH_NEW_SCRIPT", "Script", items=[
         NodeItem("ShaderNodeScript"),
diff --git a/source/blender/blenkernel/BKE_node.h b/source/blender/blenkernel/BKE_node.h
index b43747ab33a..bc1ef7ac5c9 100644
--- a/source/blender/blenkernel/BKE_node.h
+++ b/source/blender/blenkernel/BKE_node.h
@@ -742,6 +742,7 @@ struct ShadeResult;
 #define SH_NODE_WIREFRAME				178
 #define SH_NODE_BSDF_TOON				179
 #define SH_NODE_WAVELENGTH				180
+#define SH_NODE_BLACKBODY				181
 
 /* custom defines options for Material node */
 #define SH_NODE_MAT_DIFF   1
diff --git a/source/blender/blenkernel/intern/node.c b/source/blender/blenkernel/intern/node.c
index 84dfa70abfc..0cebbf03203 100644
--- a/source/blender/blenkernel/intern/node.c
+++ b/source/blender/blenkernel/intern/node.c
@@ -3406,6 +3406,7 @@ static void registerShaderNodes(void)
 	register_node_type_sh_rgb();
 	register_node_type_sh_wireframe();
 	register_node_type_sh_wavelength();
+	register_node_type_sh_blackbody();
 	register_node_type_sh_mix_rgb();
 	register_node_type_sh_valtorgb();
 	register_node_type_sh_rgbtobw();
diff --git a/source/blender/nodes/CMakeLists.txt b/source/blender/nodes/CMakeLists.txt
index cc1a5f8cee9..4b7ee2aed51 100644
--- a/source/blender/nodes/CMakeLists.txt
+++ b/source/blender/nodes/CMakeLists.txt
@@ -146,6 +146,7 @@ set(SRC
 	shader/nodes/node_shader_value.c
 	shader/nodes/node_shader_wireframe.c
 	shader/nodes/node_shader_wavelength.c
+	shader/nodes/node_shader_blackbody.c
 	shader/nodes/node_shader_vectMath.c
 	shader/nodes/node_shader_add_shader.c
 	shader/nodes/node_shader_ambient_occlusion.c
diff --git a/source/blender/nodes/NOD_shader.h b/source/blender/nodes/NOD_shader.h
index edb0ba6f475..a56d78af309 100644
--- a/source/blender/nodes/NOD_shader.h
+++ b/source/blender/nodes/NOD_shader.h
@@ -81,6 +81,7 @@ void register_node_type_sh_object_info(void);
 void register_node_type_sh_fresnel(void);
 void register_node_type_sh_wireframe(void);
 void register_node_type_sh_wavelength(void);
+void register_node_type_sh_blackbody(void);
 void register_node_type_sh_layer_weight(void);
 void register_node_type_sh_tex_coord(void);
 void register_node_type_sh_particle_info(void);
diff --git a/source/blender/nodes/NOD_static_types.h b/source/blender/nodes/NOD_static_types.h
index 69f2a0ae955..a7728cc0dde 100644
--- a/source/blender/nodes/NOD_static_types.h
+++ b/source/blender/nodes/NOD_static_types.h
@@ -97,6 +97,7 @@ DefNode( ShaderNode,     SH_NODE_PARTICLE_INFO,      0,                      "PA
 DefNode( ShaderNode,     SH_NODE_HAIR_INFO,          0,                      "HAIR_INFO",          HairInfo,         "Hair Info",         ""       )
 DefNode( ShaderNode,     SH_NODE_WIREFRAME,          def_sh_tex_wireframe,   "WIREFRAME",          Wireframe,        "Wireframe",         ""       )
 DefNode( ShaderNode,     SH_NODE_WAVELENGTH,         0,                      "WAVELENGTH",         Wavelength,       "Wavelength",        ""       )
+DefNode( ShaderNode,     SH_NODE_BLACKBODY,          0,                      "BLACKBODY",          Blackbody,        "Blackbody",         ""       )
 DefNode( ShaderNode,     SH_NODE_BUMP,               def_sh_bump,            "BUMP",               Bump,             "Bump",              ""       )
 DefNode( ShaderNode,     SH_NODE_NORMAL_MAP,         def_sh_normal_map,      "NORMAL_MAP",         NormalMap,        "Normal Map",        ""       )
 DefNode( ShaderNode,     SH_NODE_TANGENT,            def_sh_tangent,         "TANGENT",            Tangent,          "Tangent",           ""       )
diff --git a/source/blender/nodes/shader/nodes/node_shader_blackbody.c b/source/blender/nodes/shader/nodes/node_shader_blackbody.c
new file mode 100644
index 00000000000..af89a959554
--- /dev/null
+++ b/source/blender/nodes/shader/nodes/node_shader_blackbody.c
@@ -0,0 +1,54 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version. 
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2005 Blender Foundation.
+ * All rights reserved.
+ *
+ * The Original Code is: all of this file.
+ *
+ * Contributor(s): none yet.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+#include "../node_shader_util.h"
+
+/* **************** Blackbody ******************** */
+static bNodeSocketTemplate sh_node_blackbody_in[] = {
+	{	SOCK_FLOAT, 1, N_("Temperature"),	1500.0f, 0.0f, 0.0f, 0.0f, 800.0f, 12000.0f},
+	{	-1, 0, ""	}
+};
+
+static bNodeSocketTemplate sh_node_blackbody_out[] = {
+	{	SOCK_RGBA, 0, N_("Color")},
+	{	-1, 0, ""	}
+};
+
+/* node type definition */
+void register_node_type_sh_blackbody(void)
+{
+	static bNodeType ntype;
+
+	sh_node_type_base(&ntype, SH_NODE_BLACKBODY, "Blackbody", NODE_CLASS_CONVERTOR, 0);
+	node_type_compatibility(&ntype, NODE_NEW_SHADING);
+	node_type_size_preset(&ntype, NODE_SIZE_MIDDLE);
+	node_type_socket_templates(&ntype, sh_node_blackbody_in, sh_node_blackbody_out);
+	node_type_init(&ntype, NULL);
+	node_type_storage(&ntype, "", NULL, NULL);
+
+	nodeRegisterType(&ntype);
+}