Cycles: Query XYZ to/from Scene Linear conversion from OCIO instead of assuming sRGB

I've limited it to just the RGB<->XYZ stuff for now, correct image handling is the next step.

Reviewers: brecht, sergey

Differential Revision: https://developer.blender.org/D3478

16 files changed, 67 insertions, 14 deletions

diff --git a/intern/cycles/kernel/kernel_color.h b/intern/cycles/kernel/kernel_color.h
new file mode 100644
index 00000000000..d1c3dac824d
--- /dev/null
+++ b/intern/cycles/kernel/kernel_color.h
@@ -0,0 +1,38 @@
+/*
+ * Copyright 2011-2018 Blender Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __KERNEL_COLOR_H__
+#define __KERNEL_COLOR_H__
+
+#include "util/util_color.h"
+
+CCL_NAMESPACE_BEGIN
+
+ccl_device float3 xyz_to_rgb(KernelGlobals *kg, float3 xyz)
+{
+    return make_float3(dot(kernel_data.film.xyz_to_r, xyz),
+                       dot(kernel_data.film.xyz_to_g, xyz),
+                       dot(kernel_data.film.xyz_to_b, xyz));
+}
+
+ccl_device float linear_rgb_to_gray(KernelGlobals *kg, float3 c)
+{
+    return dot(c, kernel_data.film.rgb_to_y);
+}
+
+CCL_NAMESPACE_END
+
+#endif /* __KERNEL_COLOR_H__ */
\ No newline at end of file
diff --git a/intern/cycles/kernel/kernel_film.h b/intern/cycles/kernel/kernel_film.h
index f9e9b413898..94815601179 100644
--- a/intern/cycles/kernel/kernel_film.h
+++ b/intern/cycles/kernel/kernel_film.h
@@ -22,9 +22,9 @@ ccl_device float4 film_map(KernelGlobals *kg, float4 irradiance, float scale)
 	float4 result = irradiance*scale;
 
 	/* conversion to srgb */
-	result.x = color_scene_linear_to_srgb(result.x*exposure);
-	result.y = color_scene_linear_to_srgb(result.y*exposure);
-	result.z = color_scene_linear_to_srgb(result.z*exposure);
+	result.x = color_linear_to_srgb(result.x*exposure);
+	result.y = color_linear_to_srgb(result.y*exposure);
+	result.z = color_linear_to_srgb(result.z*exposure);
 
 	/* clamp since alpha might be > 1.0 due to russian roulette */
 	result.w = saturate(result.w);
diff --git a/intern/cycles/kernel/kernel_types.h b/intern/cycles/kernel/kernel_types.h
index 5382213e6f7..633518c7926 100644
--- a/intern/cycles/kernel/kernel_types.h
+++ b/intern/cycles/kernel/kernel_types.h
@@ -1272,6 +1272,11 @@ typedef struct KernelFilm {
 	int pass_denoising_clean;
 	int denoising_flags;
 
+	float3 xyz_to_r;
+	float3 xyz_to_g;
+	float3 xyz_to_b;
+	float3 rgb_to_y;
+
 	int pad1, pad2, pad3;
 
 #ifdef __KERNEL_DEBUG__
diff --git a/intern/cycles/kernel/kernels/cpu/kernel_cpu_impl.h b/intern/cycles/kernel/kernels/cpu/kernel_cpu_impl.h
index ccca023a15f..5ec1655ab05 100644
--- a/intern/cycles/kernel/kernels/cpu/kernel_cpu_impl.h
+++ b/intern/cycles/kernel/kernels/cpu/kernel_cpu_impl.h
@@ -30,6 +30,7 @@
 #    include "kernel/split/kernel_split_data.h"
 #    include "kernel/kernel_globals.h"
 
+#    include "kernel/kernel_color.h"
 #    include "kernel/kernels/cpu/kernel_cpu_image.h"
 #    include "kernel/kernel_film.h"
 #    include "kernel/kernel_path.h"
diff --git a/intern/cycles/kernel/kernels/cuda/kernel.cu b/intern/cycles/kernel/kernels/cuda/kernel.cu
index 3c93e00ccf1..8a180a509e8 100644
--- a/intern/cycles/kernel/kernels/cuda/kernel.cu
+++ b/intern/cycles/kernel/kernels/cuda/kernel.cu
@@ -26,6 +26,7 @@
 #include "kernel/kernel_math.h"
 #include "kernel/kernel_types.h"
 #include "kernel/kernel_globals.h"
+#include "kernel/kernel_color.h"
 #include "kernel/kernels/cuda/kernel_cuda_image.h"
 #include "kernel/kernel_film.h"
 #include "kernel/kernel_path.h"
diff --git a/intern/cycles/kernel/kernels/opencl/kernel.cl b/intern/cycles/kernel/kernels/opencl/kernel.cl
index 9d5d784e140..63128d0aecf 100644
--- a/intern/cycles/kernel/kernels/opencl/kernel.cl
+++ b/intern/cycles/kernel/kernels/opencl/kernel.cl
@@ -20,6 +20,7 @@
 #include "kernel/kernel_math.h"
 #include "kernel/kernel_types.h"
 #include "kernel/kernel_globals.h"
+#include "kernel/kernel_color.h"
 #include "kernel/kernels/opencl/kernel_opencl_image.h"
 
 #include "kernel/kernel_film.h"
diff --git a/intern/cycles/kernel/osl/osl_services.cpp b/intern/cycles/kernel/osl/osl_services.cpp
index 5f4baf6fda3..1aca54d2ad5 100644
--- a/intern/cycles/kernel/osl/osl_services.cpp
+++ b/intern/cycles/kernel/osl/osl_services.cpp
@@ -41,6 +41,7 @@
 #include "kernel/kernel_compat_cpu.h"
 #include "kernel/split/kernel_split_data_types.h"
 #include "kernel/kernel_globals.h"
+#include "kernel/kernel_color.h"
 #include "kernel/kernel_random.h"
 #include "kernel/kernel_projection.h"
 #include "kernel/kernel_differential.h"
diff --git a/intern/cycles/kernel/shaders/node_color.h b/intern/cycles/kernel/shaders/node_color.h
index 4a17286a07f..2c3a810cb18 100644
--- a/intern/cycles/kernel/shaders/node_color.h
+++ b/intern/cycles/kernel/shaders/node_color.h
@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+/* TODO(lukas): Fix colors in OSL. */
+
 float color_srgb_to_scene_linear(float c)
 {
 	if (c < 0.04045)
diff --git a/intern/cycles/kernel/split/kernel_split_common.h b/intern/cycles/kernel/split/kernel_split_common.h
index abe68104449..4b86696691a 100644
--- a/intern/cycles/kernel/split/kernel_split_common.h
+++ b/intern/cycles/kernel/split/kernel_split_common.h
@@ -23,6 +23,7 @@
 #include "kernel/split/kernel_split_data.h"
 
 #include "kernel/kernel_globals.h"
+#include "kernel/kernel_color.h"
 
 #ifdef __OSL__
 #  include "kernel/osl/osl_shader.h"
diff --git a/intern/cycles/kernel/svm/svm.h b/intern/cycles/kernel/svm/svm.h
index bfa146f2d93..ce2affe96c8 100644
--- a/intern/cycles/kernel/svm/svm.h
+++ b/intern/cycles/kernel/svm/svm.h
@@ -243,7 +243,7 @@ ccl_device_noinline void svm_eval_nodes(KernelGlobals *kg, ShaderData *sd, ccl_a
 				svm_node_geometry(kg, sd, stack, node.y, node.z);
 				break;
 			case NODE_CONVERT:
-				svm_node_convert(sd, stack, node.y, node.z, node.w);
+				svm_node_convert(kg, sd, stack, node.y, node.z, node.w);
 				break;
 			case NODE_TEX_COORD:
 				svm_node_tex_coord(kg, sd, path_flag, stack, node, &offset);
@@ -465,7 +465,7 @@ ccl_device_noinline void svm_eval_nodes(KernelGlobals *kg, ShaderData *sd, ccl_a
 				svm_node_wireframe(kg, sd, stack, node);
 				break;
 			case NODE_WAVELENGTH:
-				svm_node_wavelength(sd, stack, node.y, node.z);
+				svm_node_wavelength(kg, sd, stack, node.y, node.z);
 				break;
 			case NODE_BLACKBODY:
 				svm_node_blackbody(kg, sd, stack, node.y, node.z);
diff --git a/intern/cycles/kernel/svm/svm_closure.h b/intern/cycles/kernel/svm/svm_closure.h
index 886a1333fa3..76464e37c66 100644
--- a/intern/cycles/kernel/svm/svm_closure.h
+++ b/intern/cycles/kernel/svm/svm_closure.h
@@ -217,7 +217,7 @@ ccl_device void svm_node_closure_bsdf(KernelGlobals *kg, ShaderData *sd, float *
 
 			/* sheen */
 			if(diffuse_weight > CLOSURE_WEIGHT_CUTOFF && sheen > CLOSURE_WEIGHT_CUTOFF) {
-				float m_cdlum = linear_rgb_to_gray(base_color);
+				float m_cdlum = linear_rgb_to_gray(kg, base_color);
 				float3 m_ctint = m_cdlum > 0.0f ? base_color / m_cdlum : make_float3(1.0f, 1.0f, 1.0f); // normalize lum. to isolate hue+sat
 
 				/* color of the sheen component */
diff --git a/intern/cycles/kernel/svm/svm_convert.h b/intern/cycles/kernel/svm/svm_convert.h
index 34080377083..c88ac57e20d 100644
--- a/intern/cycles/kernel/svm/svm_convert.h
+++ b/intern/cycles/kernel/svm/svm_convert.h
@@ -18,7 +18,7 @@ CCL_NAMESPACE_BEGIN
 
 /* Conversion Nodes */
 
-ccl_device void svm_node_convert(ShaderData *sd, float *stack, uint type, uint from, uint to)
+ccl_device void svm_node_convert(KernelGlobals *kg, ShaderData *sd, float *stack, uint type, uint from, uint to)
 {
 	switch(type) {
 		case NODE_CONVERT_FI: {
@@ -33,13 +33,13 @@ ccl_device void svm_node_convert(ShaderData *sd, float *stack, uint type, uint f
 		}
 		case NODE_CONVERT_CF: {
 			float3 f = stack_load_float3(stack, from);
-			float g = linear_rgb_to_gray(f);
+			float g = linear_rgb_to_gray(kg, f);
 			stack_store_float(stack, to, g);
 			break;
 		}
 		case NODE_CONVERT_CI: {
 			float3 f = stack_load_float3(stack, from);
-			int i = (int)linear_rgb_to_gray(f);
+			int i = (int)linear_rgb_to_gray(kg, f);
 			stack_store_int(stack, to, i);
 			break;
 		}
diff --git a/intern/cycles/kernel/svm/svm_image.h b/intern/cycles/kernel/svm/svm_image.h
index 4226e7adfe0..28565308867 100644
--- a/intern/cycles/kernel/svm/svm_image.h
+++ b/intern/cycles/kernel/svm/svm_image.h
@@ -33,7 +33,8 @@ ccl_device float4 svm_image_texture(KernelGlobals *kg, int id, float x, float y,
 	}
 
 	if(srgb) {
-		r = color_srgb_to_scene_linear_v4(r);
+		/* TODO(lukas): Implement proper conversion for image textures. */
+		r = color_srgb_to_linear_v4(r);
 	}
 
 	return r;
diff --git a/intern/cycles/kernel/svm/svm_math_util.h b/intern/cycles/kernel/svm/svm_math_util.h
index 8e6bc73ddc7..caf0addbf35 100644
--- a/intern/cycles/kernel/svm/svm_math_util.h
+++ b/intern/cycles/kernel/svm/svm_math_util.h
@@ -138,6 +138,8 @@ ccl_static_constant float blackbody_table_b[6][4] = {
 
 ccl_device float3 svm_math_blackbody_color(float t)
 {
+	/* TODO(lukas): Reimplement in XYZ. */
+
 	if(t >= 12000.0f) {
 		return make_float3(0.826270103f, 0.994478524f, 1.56626022f);
 	}
diff --git a/intern/cycles/kernel/svm/svm_sky.h b/intern/cycles/kernel/svm/svm_sky.h
index 854e85fd326..b83a7168541 100644
--- a/intern/cycles/kernel/svm/svm_sky.h
+++ b/intern/cycles/kernel/svm/svm_sky.h
@@ -59,7 +59,7 @@ ccl_device float3 sky_radiance_old(KernelGlobals *kg, float3 dir,
 
 	/* convert to RGB */
 	float3 xyz = xyY_to_xyz(x, y, Y);
-	return xyz_to_rgb(xyz.x, xyz.y, xyz.z);
+	return xyz_to_rgb(kg, xyz);
 }
 
 /*
@@ -102,7 +102,7 @@ ccl_device float3 sky_radiance_new(KernelGlobals *kg, float3 dir,
 	float z = sky_radiance_internal(config_z, theta, gamma) * radiance_z;
 
 	/* convert to RGB and adjust strength */
-	return xyz_to_rgb(x, y, z) * (M_2PI_F/683);
+	return xyz_to_rgb(kg, make_float3(x, y, z)) * (M_2PI_F/683);
 }
 
 ccl_device void svm_node_tex_sky(KernelGlobals *kg, ShaderData *sd, float *stack, uint4 node, int *offset)
diff --git a/intern/cycles/kernel/svm/svm_wavelength.h b/intern/cycles/kernel/svm/svm_wavelength.h
index 855b356b397..62e026278ac 100644
--- a/intern/cycles/kernel/svm/svm_wavelength.h
+++ b/intern/cycles/kernel/svm/svm_wavelength.h
@@ -70,7 +70,7 @@ ccl_static_constant float cie_colour_match[81][3] = {
 	{0.0001f,0.0000f,0.0000f}, {0.0001f,0.0000f,0.0000f}, {0.0000f,0.0000f,0.0000f}
 };
 
-ccl_device void svm_node_wavelength(ShaderData *sd, float *stack, uint wavelength, uint color_out)
+ccl_device void svm_node_wavelength(KernelGlobals *kg, ShaderData *sd, float *stack, uint wavelength, uint color_out)
 {	
 	float lambda_nm = stack_load_float(stack, wavelength);
 	float ii = (lambda_nm-380.0f) * (1.0f/5.0f);  // scaled 0..80
@@ -86,7 +86,7 @@ ccl_device void svm_node_wavelength(ShaderData *sd, float *stack, uint wavelengt
 		color = interp(make_float3(c[0], c[1], c[2]), make_float3(c[3], c[4], c[5]), ii);
 	}
 	
-	color = xyz_to_rgb(color.x, color.y, color.z);
+	color = xyz_to_rgb(kg, color);
 	color *= 1.0f/2.52f;	// Empirical scale from lg to make all comps <= 1
 	
 	/* Clamp to zero if values are smaller */