[Bf-blender-cvs] [8ce1090] master: Cycles: Ashikhmin-Shirley anisotropic BSDF

Karsten Schwenk noreply at git.blender.org
Sat Jun 14 13:55:35 CEST 2014


Commit: 8ce1090d4e8160165281be4b0827dbc1ba28dc8a
Author: Karsten Schwenk
Date:   Sun Jun 8 12:16:28 2014 +0200
https://developer.blender.org/rB8ce1090d4e8160165281be4b0827dbc1ba28dc8a

Cycles: Ashikhmin-Shirley anisotropic BSDF

* Ashikhmin-Shirley anisotropic BSDF was added as closure
* Anisotropic BSDF node now has two distributions

Reviewers: brecht, dingto

Differential Revision: https://developer.blender.org/D549

===================================================================

M	intern/cycles/app/cycles_xml.cpp
M	intern/cycles/blender/blender_shader.cpp
M	intern/cycles/kernel/CMakeLists.txt
M	intern/cycles/kernel/closure/bsdf.h
A	intern/cycles/kernel/closure/bsdf_ashikhmin_shirley.h
M	intern/cycles/kernel/osl/osl_closures.cpp
M	intern/cycles/kernel/shaders/CMakeLists.txt
A	intern/cycles/kernel/shaders/node_anisotropic_bsdf.osl
D	intern/cycles/kernel/shaders/node_ward_bsdf.osl
M	intern/cycles/kernel/shaders/stdosl.h
M	intern/cycles/kernel/svm/svm_closure.h
M	intern/cycles/kernel/svm/svm_types.h
M	intern/cycles/render/nodes.cpp
M	intern/cycles/render/nodes.h
M	source/blender/editors/space_node/drawnode.c
M	source/blender/makesdna/DNA_node_types.h
M	source/blender/makesrna/intern/rna_nodetree.c
M	source/blender/nodes/NOD_static_types.h

===================================================================

diff --git a/intern/cycles/app/cycles_xml.cpp b/intern/cycles/app/cycles_xml.cpp
index f50a952..915ef96 100644
--- a/intern/cycles/app/cycles_xml.cpp
+++ b/intern/cycles/app/cycles_xml.cpp
@@ -509,8 +509,10 @@ static void xml_read_shader_graph(const XMLReadState& state, Shader *shader, pug
 		else if(string_iequals(node.name(), "mapping")) {
 			snode = new MappingNode();
 		}
-		else if(string_iequals(node.name(), "ward_bsdf")) {
-			snode = new WardBsdfNode();
+		else if(string_iequals(node.name(), "anisotropic_bsdf")) {
+			AnisotropicBsdfNode *aniso = new AnisotropicBsdfNode();
+			xml_read_enum(&aniso->distribution, AnisotropicBsdfNode::distribution_enum, node, "distribution");
+			snode = aniso;
 		}
 		else if(string_iequals(node.name(), "diffuse_bsdf")) {
 			snode = new DiffuseBsdfNode();
diff --git a/intern/cycles/blender/blender_shader.cpp b/intern/cycles/blender/blender_shader.cpp
index 3b783d3..226e7a7 100644
--- a/intern/cycles/blender/blender_shader.cpp
+++ b/intern/cycles/blender/blender_shader.cpp
@@ -318,7 +318,21 @@ static ShaderNode *add_node(Scene *scene, BL::BlendData b_data, BL::Scene b_scen
 		node = new HoldoutNode();
 	}
 	else if (b_node.is_a(&RNA_ShaderNodeBsdfAnisotropic)) {
-		node = new WardBsdfNode();
+		BL::ShaderNodeBsdfAnisotropic b_aniso_node(b_node);
+		AnisotropicBsdfNode *aniso = new AnisotropicBsdfNode();
+
+		switch (b_aniso_node.distribution())
+		{
+		case BL::ShaderNodeBsdfAnisotropic::distribution_ASHIKHMIN_SHIRLEY:
+			aniso->distribution = ustring("Ashikhmin-Shirley");
+			break;
+		case BL::ShaderNodeBsdfAnisotropic::distribution_WARD:
+		default:
+			aniso->distribution = ustring("Ward");
+			break;
+		}
+
+		node = aniso;
 	}
 	else if (b_node.is_a(&RNA_ShaderNodeBsdfDiffuse)) {
 		node = new DiffuseBsdfNode();
diff --git a/intern/cycles/kernel/CMakeLists.txt b/intern/cycles/kernel/CMakeLists.txt
index d34a045..6b6fcb1 100644
--- a/intern/cycles/kernel/CMakeLists.txt
+++ b/intern/cycles/kernel/CMakeLists.txt
@@ -61,6 +61,7 @@ set(SRC_CLOSURE_HEADERS
 	closure/bsdf_transparent.h
 	closure/bsdf_util.h
 	closure/bsdf_ward.h
+	closure/bsdf_ashikhmin_shirley.h
 	closure/bsdf_westin.h
 	closure/bsdf_hair.h
 	closure/bssrdf.h
diff --git a/intern/cycles/kernel/closure/bsdf.h b/intern/cycles/kernel/closure/bsdf.h
index 24b54cd..371d0bf 100644
--- a/intern/cycles/kernel/closure/bsdf.h
+++ b/intern/cycles/kernel/closure/bsdf.h
@@ -25,6 +25,7 @@
 #include "../closure/bsdf_transparent.h"
 #ifdef __ANISOTROPIC__
 #include "../closure/bsdf_ward.h"
+#include "../closure/bsdf_ashikhmin_shirley.h"
 #endif
 #include "../closure/bsdf_westin.h"
 #include "../closure/bsdf_toon.h"
@@ -97,6 +98,10 @@ ccl_device int bsdf_sample(KernelGlobals *kg, const ShaderData *sd, const Shader
 			label = bsdf_ward_sample(sc, sd->Ng, sd->I, sd->dI.dx, sd->dI.dy, randu, randv,
 				eval, omega_in, &domega_in->dx, &domega_in->dy, pdf);
 			break;
+		case CLOSURE_BSDF_ASHIKHMIN_SHIRLEY_ID:
+			label = bsdf_ashikhmin_shirley_sample(sc, sd->Ng, sd->I, sd->dI.dx, sd->dI.dy, randu, randv,
+				eval, omega_in, &domega_in->dx, &domega_in->dy, pdf);
+			break;
 #endif
 		case CLOSURE_BSDF_ASHIKHMIN_VELVET_ID:
 			label = bsdf_ashikhmin_velvet_sample(sc, sd->Ng, sd->I, sd->dI.dx, sd->dI.dy, randu, randv,
@@ -189,6 +194,9 @@ ccl_device float3 bsdf_eval(KernelGlobals *kg, const ShaderData *sd, const Shade
 			case CLOSURE_BSDF_WARD_ID:
 				eval = bsdf_ward_eval_reflect(sc, sd->I, omega_in, pdf);
 				break;
+			case CLOSURE_BSDF_ASHIKHMIN_SHIRLEY_ID:
+				eval = bsdf_ashikhmin_shirley_eval_reflect(sc, sd->I, omega_in, pdf);
+				break;
 #endif
 			case CLOSURE_BSDF_ASHIKHMIN_VELVET_ID:
 				eval = bsdf_ashikhmin_velvet_eval_reflect(sc, sd->I, omega_in, pdf);
@@ -256,6 +264,9 @@ ccl_device float3 bsdf_eval(KernelGlobals *kg, const ShaderData *sd, const Shade
 			case CLOSURE_BSDF_WARD_ID:
 				eval = bsdf_ward_eval_transmit(sc, sd->I, omega_in, pdf);
 				break;
+			case CLOSURE_BSDF_ASHIKHMIN_SHIRLEY_ID:
+				eval = bsdf_ashikhmin_shirley_eval_transmit(sc, sd->I, omega_in, pdf);
+				break;
 #endif
 			case CLOSURE_BSDF_ASHIKHMIN_VELVET_ID:
 				eval = bsdf_ashikhmin_velvet_eval_transmit(sc, sd->I, omega_in, pdf);
@@ -341,6 +352,9 @@ ccl_device void bsdf_blur(KernelGlobals *kg, ShaderClosure *sc, float roughness)
 		case CLOSURE_BSDF_WARD_ID:
 			bsdf_ward_blur(sc, roughness);
 			break;
+		case CLOSURE_BSDF_ASHIKHMIN_SHIRLEY_ID:
+			bsdf_ashikhmin_shirley_blur(sc, roughness);
+			break;
 #endif
 		case CLOSURE_BSDF_ASHIKHMIN_VELVET_ID:
 			bsdf_ashikhmin_velvet_blur(sc, roughness);
diff --git a/intern/cycles/kernel/closure/bsdf_ashikhmin_shirley.h b/intern/cycles/kernel/closure/bsdf_ashikhmin_shirley.h
new file mode 100644
index 0000000..ea5b610
--- /dev/null
+++ b/intern/cycles/kernel/closure/bsdf_ashikhmin_shirley.h
@@ -0,0 +1,196 @@
+/*
+ * 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
+ */
+
+#ifndef __BSDF_ASHIKHMIN_SHIRLEY_H__
+#define __BSDF_ASHIKHMIN_SHIRLEY_H__
+
+/*
+ASHIKHMIN SHIRLEY BSDF
+
+Implementation of
+Michael Ashikhmin and Peter Shirley: "An Anisotropic Phong BRDF Model" (2000)
+
+The Fresnel factor is missing to get a separable bsdf (intensity*color), as is
+the case with all other microfacet-based BSDF implementations in Cycles.
+
+Other than that, the implementation directly follows the paper.
+*/
+
+CCL_NAMESPACE_BEGIN
+
+
+ccl_device int bsdf_ashikhmin_shirley_setup(ShaderClosure *sc)
+{
+	sc->data0 = clamp(sc->data0, 1e-4f, 1.0f); /* store roughness. could already convert to exponent to save some cycles in eval, */
+	sc->data1 = clamp(sc->data1, 1e-4f, 1.0f); /* but this is more consistent with other bsdfs and shader_blur. */
+
+	sc->type = CLOSURE_BSDF_ASHIKHMIN_SHIRLEY_ID;
+	return SD_BSDF | SD_BSDF_HAS_EVAL | SD_BSDF_GLOSSY;
+}
+
+ccl_device void bsdf_ashikhmin_shirley_blur(ShaderClosure *sc, float roughness)
+{
+	sc->data0 = fmaxf(roughness, sc->data0); /* clamp roughness */
+	sc->data1 = fmaxf(roughness, sc->data1);
+}
+
+ccl_device_inline float bsdf_ashikhmin_shirley_roughness_to_exponent(float roughness)
+{
+	return 2.0f / (roughness*roughness) - 2.0f;
+}
+
+ccl_device float3 bsdf_ashikhmin_shirley_eval_reflect(const ShaderClosure *sc, const float3 I, const float3 omega_in, float *pdf)
+{
+	float3 N = sc->N;
+	float3 T = sc->T;
+
+	float NdotI = dot(N, I);           /* in Cycles/OSL convention I is omega_out    */
+	float NdotO = dot(N, omega_in);    /* and consequently we use for O omaga_in ;)  */
+
+	float out = 0.0f;
+
+	if (NdotI > 0.0f && NdotO > 0.0f) {
+		NdotI = fmaxf(NdotI, 1e-6f);
+		NdotO = fmaxf(NdotO, 1e-6f);
+		float3 H = normalize(omega_in + I);
+		float HdotI = fmaxf(dot(H, I), 1e-6f);
+		float HdotN = fmaxf(dot(H, N), 1e-6f);
+
+		float pump = 1.0f / fmaxf(1e-6f, (HdotI*fmaxf(NdotO, NdotI))); /* pump from original paper (first derivative disc., but cancels the HdotI in the pdf nicely) */
+		/*float pump = 1.0f / fmaxf(1e-4f, ((NdotO + NdotI) * (NdotO*NdotI))); */ /* pump from d-brdf paper */
+
+		float n_x = bsdf_ashikhmin_shirley_roughness_to_exponent(sc->data0);
+		float n_y = bsdf_ashikhmin_shirley_roughness_to_exponent(sc->data1);
+
+		if (n_x == n_y) {  /* => isotropic case */
+			float e = n_x;
+			float lobe = powf(HdotN, e);
+			float norm = (n_x + 1.0f) / (8.0f * M_PI_F);
+
+			out = NdotO * norm * lobe * pump;
+			*pdf = norm * lobe / HdotI; /* this is p_h / 4(H.I)  (conversion from 'wh measure' to 'wi measure', eq. 8 in paper) */
+		}
+		else {             /* => ANisotropic case */
+			float3 X, Y;
+			make_orthonormals_tangent(N, T, &X, &Y);
+
+			float HdotX = dot(H, X);
+			float HdotY = dot(H, Y);
+			float e = (n_x * HdotX*HdotX + n_y * HdotY*HdotY) / (1.0f - HdotN*HdotN);
+			float lobe = powf(HdotN, e);
+			float norm = sqrtf((n_x + 1.0f)*(n_y + 1.0f)) / (8.0f * M_PI_F);
+			
+			out = NdotO * norm * lobe * pump;
+			*pdf = norm * lobe / HdotI;
+		}
+	}
+
+	return make_float3(out, out, out);
+}
+
+ccl_device float3 bsdf_ashikhmin_shirley_eval_transmit(const ShaderClosure *sc, const float3 I, const float3 omega_in, float *pdf)
+{
+	return make_float3(0.0f, 0.0f, 0.0f);
+}
+
+ccl_device_inline void bsdf_ashikhmin_shirley_sample_first_quadrant(float n_x, float n_y, float randu, float randv, float *phi, float *cos_theta)
+{
+	*phi = atanf(sqrtf((n_x + 1.0f) / (n_y + 1.0f)) * tanf(M_PI_2_F * randu));
+	float cos_phi = cosf(*phi);
+	float sin_phi = sinf(*phi);
+	*cos_theta = powf(randv, 1.0f / (n_x * cos_phi*cos_phi + n_y * sin_phi*sin_phi + 1.0f));
+}
+
+ccl_device int bsdf_ashikhmin_shirley_sample(const ShaderClosure *sc, float3 Ng, float3 I, float3 dIdx, float3 dIdy, float randu, float randv, float3 *eval, float3 *omega_in, float3 *domega_in_dx, float3 *domega_in_dy, float *pdf)
+{
+	float3 N = sc->N;
+	float3 T = sc->T;
+
+	float NdotI = dot(N, I);
+	if (NdotI > 0.0f) {
+
+		float n_x = bsdf_ashikhmin_shirley_roughness_to_exponent(sc->data0);
+		float n_y = bsdf_ashikhmin_shirley_roughness_to_exponent(sc->data1);
+
+		/* get x,y basis on the surface for anisotropy */
+		float3 X, Y;
+		make_orthonormals_tangent(N, T, &X, &Y);
+
+		/* sample spherical coords for h in tangent space */
+		float phi;
+		float cos_theta;
+		if (n_x == n_y) {  /* => simple isotropic sampling */
+			phi = M_2PI_F * randu;
+			cos_theta = powf(randv, 1.0f / (n_x + 1.0f));
+		}
+		else {             /* => more complex anisotropic sampling */
+			if (randu < 0.25f) {      /* first quadrant */
+				float remapped_randu = 4.0f * randu;
+				bsdf_ashikhmin_shirley_sample_first_quadrant(n_x, n_y, remapped_randu, randv, &phi, &cos_theta);
+			}
+			else if (randu < 0.5f) {  /* second quadrant */
+				float remapped_randu = 4.0f * (.5f - randu);
+				bsdf_ashikhmi

@@ Diff output truncated at 10240 characters. @@




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