Cycles: add Displacement node.

This converts object space height to world space displacement, to be
linked to the new vector displacement material output.

Differential Revision: https://developer.blender.org/D3015

5 files changed, 56 insertions, 5 deletions

diff --git a/intern/cycles/kernel/shaders/CMakeLists.txt b/intern/cycles/kernel/shaders/CMakeLists.txt
index 83cfdbcf8ba..fb983a44579 100644
--- a/intern/cycles/kernel/shaders/CMakeLists.txt
+++ b/intern/cycles/kernel/shaders/CMakeLists.txt
@@ -23,6 +23,7 @@ set(SRC_OSL
 	node_convert_from_point.osl
 	node_convert_from_vector.osl
 	node_diffuse_bsdf.osl
+	node_displacement.osl
 	node_emission.osl
 	node_environment_texture.osl
 	node_fresnel.osl
diff --git a/intern/cycles/kernel/shaders/node_displacement.osl b/intern/cycles/kernel/shaders/node_displacement.osl
new file mode 100644
index 00000000000..fb81533c778
--- /dev/null
+++ b/intern/cycles/kernel/shaders/node_displacement.osl
@@ -0,0 +1,29 @@
+/*
+ * Copyright 2011-2013 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.
+ */
+
+#include "stdosl.h"
+
+shader node_displacement(
+	float Height = 0.0,
+	float Scale = 1.0,
+	normal Normal = N,
+	output vector Displacement = vector(0.0, 0.0, 0.0))
+{
+	Displacement = normalize(transform("object", Normal));
+	Displacement *= Height * Scale;
+	Displacement = transform("object", "world", Displacement);
+}
+
diff --git a/intern/cycles/kernel/svm/svm.h b/intern/cycles/kernel/svm/svm.h
index d3dac5706d0..cbc603d4645 100644
--- a/intern/cycles/kernel/svm/svm.h
+++ b/intern/cycles/kernel/svm/svm.h
@@ -267,6 +267,9 @@ ccl_device_noinline void svm_eval_nodes(KernelGlobals *kg, ShaderData *sd, ccl_a
 			case NODE_SET_DISPLACEMENT:
 				svm_node_set_displacement(kg, sd, stack, node.y);
 				break;
+			case NODE_DISPLACEMENT:
+				svm_node_displacement(kg, sd, stack, node);
+				break;
 #  endif  /* NODES_FEATURE(NODE_FEATURE_BUMP) */
 #  ifdef __TEXTURES__
 			case NODE_TEX_IMAGE:
diff --git a/intern/cycles/kernel/svm/svm_displace.h b/intern/cycles/kernel/svm/svm_displace.h
index 656357be52d..1ac2c8fd52e 100644
--- a/intern/cycles/kernel/svm/svm_displace.h
+++ b/intern/cycles/kernel/svm/svm_displace.h
@@ -22,8 +22,8 @@ ccl_device void svm_node_set_bump(KernelGlobals *kg, ShaderData *sd, float *stac
 {
 #ifdef __RAY_DIFFERENTIALS__
 	/* get normal input */
-	uint normal_offset, distance_offset, invert, use_object_space;
-	decode_node_uchar4(node.y, &normal_offset, &distance_offset, &invert, &use_object_space);
+	uint normal_offset, scale_offset, invert, use_object_space;
+	decode_node_uchar4(node.y, &normal_offset, &scale_offset, &invert, &use_object_space);
 
 	float3 normal_in = stack_valid(normal_offset)? stack_load_float3(stack, normal_offset): sd->N;
 
@@ -55,15 +55,15 @@ ccl_device void svm_node_set_bump(KernelGlobals *kg, ShaderData *sd, float *stac
 	float absdet = fabsf(det);
 
 	float strength = stack_load_float(stack, strength_offset);
-	float distance = stack_load_float(stack, distance_offset);
+	float scale = stack_load_float(stack, scale_offset);
 
 	if(invert)
-		distance *= -1.0f;
+		scale *= -1.0f;
 
 	strength = max(strength, 0.0f);
 
 	/* compute and output perturbed normal */
-	float3 normal_out = safe_normalize(absdet*normal_in - distance*signf(det)*surfgrad);
+	float3 normal_out = safe_normalize(absdet*normal_in - scale*signf(det)*surfgrad);
 	if(is_zero(normal_out)) {
 		normal_out = normal_in;
 	}
@@ -95,5 +95,22 @@ ccl_device void svm_node_set_displacement(KernelGlobals *kg, ShaderData *sd, flo
 	sd->P += dP;
 }
 
+ccl_device void svm_node_displacement(KernelGlobals *kg, ShaderData *sd, float *stack, uint4 node)
+{
+	uint height_offset, scale_offset, normal_offset, displacement_offset;
+	decode_node_uchar4(node.y, &height_offset, &scale_offset, &normal_offset, &displacement_offset);
+
+	float height = stack_load_float(stack, height_offset);
+	float scale = stack_load_float(stack, scale_offset);
+	float3 normal = stack_valid(normal_offset)? stack_load_float3(stack, normal_offset): sd->N;
+
+	float3 dP = normal;
+	object_inverse_normal_transform(kg, sd, &dP);
+	dP *= height * scale;
+	object_dir_transform(kg, sd, &dP);
+
+	stack_store_float3(stack, displacement_offset, dP);
+}
+
 CCL_NAMESPACE_END
 
diff --git a/intern/cycles/kernel/svm/svm_types.h b/intern/cycles/kernel/svm/svm_types.h
index c7fe7948422..00c7752da8c 100644
--- a/intern/cycles/kernel/svm/svm_types.h
+++ b/intern/cycles/kernel/svm/svm_types.h
@@ -133,6 +133,7 @@ typedef enum ShaderNodeType {
 	NODE_ENTER_BUMP_EVAL,
 	NODE_LEAVE_BUMP_EVAL,
 	NODE_BEVEL,
+	NODE_DISPLACEMENT,
 } ShaderNodeType;
 
 typedef enum NodeAttributeType {