source/blender/nodes/shader/CMakeLists.txt

@@ -21,6 +21,12 @@ set(INC
   ${CMAKE_BINARY_DIR}/source/blender/makesrna
 )
 
+if(WITH_HYDRA)
+  list(APPEND INC
+    ../../io/usd
+  )
+  add_definitions(-DWITH_HYDRA)
+endif()
 
 set(SRC
   nodes/node_shader_add_shader.cc
@@ -138,8 +144,16 @@ if(WITH_MATERIALX)
   list(APPEND LIB MaterialXCore)
   list(APPEND SRC
     materialx/material.cc
+    materialx/nodes/node.cc
+    materialx/nodes/material_output.cc
+    materialx/nodes/principled_bsdf.cc
+    materialx/nodes/image.cc
 
     materialx/material.h
+    materialx/nodes/node.h
+    materialx/nodes/material_output.h
+    materialx/nodes/principled_bsdf.h
+    materialx/nodes/image.h
   )
 endif()
 

source/blender/nodes/shader/materialx/material.cc

@@ -3,11 +3,23 @@
  * SPDX-License-Identifier: GPL-2.0-or-later */
 
 #include "material.h"
+#include "nodes/material_output.h"
 
 #include <MaterialXCore/Node.h>
 
+#include "NOD_shader.h"
+
 namespace blender::nodes::materialx {
 
+static void export_nodegraph(MaterialX::DocumentPtr doc, Depsgraph *depsgraph, Material *material)
+{
+  material->nodetree->ensure_topology_cache();
+
+  bNode *output_node = ntreeShaderOutputNode(material->nodetree, SHD_OUTPUT_ALL);
+  MaterialXMaterialOutputNode material_node(doc, depsgraph, material, output_node);
+  material_node.convert();
+}
+
 static void create_standard_surface(MaterialX::DocumentPtr doc, Material *material)
 {
   MaterialX::NodePtr surfacematerial = doc->addNode(
@@ -17,16 +29,17 @@ static void create_standard_surface(MaterialX::DocumentPtr doc, Material *materi
 
   standard_surface->addInput("base", "float")->setValue(1.0);
   standard_surface->addInput("base_color", "color3")
-      ->setValue(MaterialX::Color3(material->r, material->g, material->a));
+      ->setValue(MaterialX::Color3(material->r, material->g, material->b));
 
   surfacematerial->addInput(standard_surface->getType(), standard_surface->getType())
       ->setNodeName(standard_surface->getName());
 }
 
-MaterialX::DocumentPtr export_to_materialx(Material* material) {
+MaterialX::DocumentPtr export_to_materialx(Depsgraph *depsgraph, Material *material)
+{
   MaterialX::DocumentPtr doc = MaterialX::createDocument();
   if (material->use_nodes) {
-    ;
+    export_nodegraph(doc, depsgraph, material);
   }
   else {
     create_standard_surface(doc, material);
@@ -34,5 +47,4 @@ MaterialX::DocumentPtr export_to_materialx(Material* material) {
   return doc;
 }
 
-}  // namespace blender::materialx
-
+}  // namespace blender::nodes::materialx

source/blender/nodes/shader/materialx/material.h

@@ -6,11 +6,11 @@
 
 #include <MaterialXCore/Document.h>
 
+#include "DEG_depsgraph.h"
 #include "DNA_material_types.h"
 
 namespace blender::nodes::materialx {
 
-MaterialX::DocumentPtr export_to_materialx(Material *material);
-
-}  // namespace blender::materialx
+MaterialX::DocumentPtr export_to_materialx(Depsgraph *depsgraph, Material *material);
 
+}  // namespace blender::nodes::materialx

source/blender/nodes/shader/materialx/nodes/image.cc

@@ -0,0 +1,43 @@
+/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include "node.h"
+#include "image.h"
+
+#include "hydra/image.h"
+
+#include "DEG_depsgraph_query.h"
+
+namespace blender::nodes::materialx {
+
+const MaterialX::Color3 MaterialXTexImageNode::texture_error_color_{1.0, 0.0, 1.0};
+
+MaterialXTexImageNode::MaterialXTexImageNode(MaterialX::DocumentPtr doc,
+                                             const Depsgraph *depsgraph,
+                                             const Material *material,
+                                             const bNode *node)
+    : MaterialXNode(doc, depsgraph, material, node)
+{
+  matx_node = doc->addNode("image", MaterialX::createValidName(node->name), "color3");
+}
+
+MaterialX::NodePtr MaterialXTexImageNode::convert()
+{
+  Image *image = (Image *)node->id;
+  NodeTexImage *tex = static_cast<NodeTexImage *>(node->storage);
+  Scene *scene = DEG_get_input_scene(depsgraph);
+  Main *bmain = DEG_get_bmain(depsgraph);
+  std::string image_path;
+#ifdef WITH_HYDRA
+  image_path = io::hydra::cache_or_get_image_file(bmain, scene, image, &tex->iuser);
+#endif
+  MaterialX::NodePtr uv_node = doc->addNode("texcoord", MaterialX::EMPTY_STRING, "vector2");
+
+  matx_node->addInput("file", "filename")->setValue(image_path);
+  matx_node->addInput("texcoord", "vector2")->setNodeName(uv_node->getName());
+
+  return matx_node;
+}
+
+}  // namespace blender::nodes::materialx

source/blender/nodes/shader/materialx/nodes/image.h

@@ -0,0 +1,24 @@
+/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later */
+
+#pragma once
+
+#include "node.h"
+
+namespace blender::nodes::materialx {
+
+class MaterialXTexImageNode : public MaterialXNode {
+ protected:
+  /* Following Cycles color for wrong Texture nodes. */
+  static const MaterialX::Color3 texture_error_color_;
+
+ public:
+  MaterialXTexImageNode(MaterialX::DocumentPtr doc,
+                        const Depsgraph *depsgraph,
+                        const Material *material,
+                        const bNode *node);
+  MaterialX::NodePtr convert() override;
+};
+
+}  // namespace blender::nodes::materialx

source/blender/nodes/shader/materialx/nodes/material_output.cc

@@ -0,0 +1,35 @@
+/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include "material_output.h"
+#include "principled_bsdf.h"
+
+namespace blender::nodes::materialx {
+
+MaterialXMaterialOutputNode::MaterialXMaterialOutputNode(MaterialX::DocumentPtr doc,
+                                                         const Depsgraph *depsgraph,
+                                                         const Material *material,
+                                                         const bNode *node)
+    : MaterialXNode(doc, depsgraph, material, node)
+{
+  matx_node = doc->addNode("surfacematerial", MaterialX::createValidName(node->name), "material");
+}
+
+MaterialX::NodePtr MaterialXMaterialOutputNode::convert()
+{
+  LISTBASE_FOREACH (const bNodeSocket *, sock, &node->inputs) {
+    if (!sock->link) {
+      continue;
+    }
+    if (STREQ(sock->name, "Surface")) {
+      const bNode *inode = sock->link->fromnode;
+      MaterialXPrincipledBSDFNode surface_node(doc, depsgraph, material, inode);
+      surface_node.convert();
+      matx_node->addInput("surfaceshader", "surfaceshader")->setNodeName(inode->name);
+    }
+  }
+  return matx_node;
+}
+
+}  // namespace blender::nodes::materialx

source/blender/nodes/shader/materialx/nodes/material_output.h

@@ -0,0 +1,20 @@
+/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later */
+
+#pragma once
+
+#include "node.h"
+
+namespace blender::nodes::materialx {
+
+class MaterialXMaterialOutputNode : public MaterialXNode {
+ public:
+  MaterialXMaterialOutputNode(MaterialX::DocumentPtr doc,
+                              const Depsgraph *depsgraph,
+                              const Material *material,
+                              const bNode *node);
+  MaterialX::NodePtr convert() override;
+};
+
+}  // namespace blender::nodes::materialx

source/blender/nodes/shader/materialx/nodes/node.cc

@@ -0,0 +1,17 @@
+/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include "node.h"
+
+namespace blender::nodes::materialx {
+
+MaterialXNode::MaterialXNode(MaterialX::DocumentPtr doc,
+                             const Depsgraph *depsgraph,
+                             const Material *material,
+                             const bNode *node)
+    : depsgraph(depsgraph), material(material), node(node), doc(doc)
+{
+}
+
+}  // namespace blender::nodes::materialx

source/blender/nodes/shader/materialx/nodes/node.h

@@ -0,0 +1,33 @@
+/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later */
+
+#pragma once
+
+#include <MaterialXCore/Document.h>
+
+#include "DEG_depsgraph.h"
+#include "DNA_material_types.h"
+#include "DNA_node_types.h"
+
+namespace blender::nodes::materialx {
+
+class MaterialXNode {
+ public:
+  const Depsgraph *depsgraph = nullptr;
+  const Material *material = nullptr;
+  const bNode *node = nullptr;
+  MaterialX::NodePtr matx_node;
+  MaterialX::DocumentPtr doc;
+
+ public:
+  MaterialXNode(MaterialX::DocumentPtr doc,
+                const Depsgraph *depsgraph,
+                const Material *material,
+                const bNode *node);
+  virtual ~MaterialXNode() = default;
+
+  virtual MaterialX::NodePtr convert() = 0;
+};
+
+}  // namespace blender::nodes::materialx

source/blender/nodes/shader/materialx/nodes/principled_bsdf.cc

@@ -0,0 +1,126 @@
+/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include "principled_bsdf.h"
+
+#include <BKE_node_runtime.hh>
+
+namespace blender::nodes::materialx {
+
+const MaterialX::Color3 MaterialXPrincipledBSDFNode::default_white_color_{1.0, 1.0, 1.0};
+
+MaterialXPrincipledBSDFNode::MaterialXPrincipledBSDFNode(MaterialX::DocumentPtr doc,
+                                                         const Depsgraph *depsgraph,
+                                                         const Material *material,
+                                                         const bNode *node)
+    : MaterialXNode(doc, depsgraph, material, node)
+{
+  matx_node = doc->addNode(
+      "standard_surface", MaterialX::createValidName(node->name), "surfaceshader");
+}
+
+MaterialX::NodePtr MaterialXPrincipledBSDFNode::convert()
+{
+#pragma region get inputs
+  const float *base_color =
+      node->input_by_identifier("Base Color").default_value_typed<bNodeSocketValueRGBA>()->value;
+  const float subsurface =
+      node->input_by_identifier("Subsurface").default_value_typed<bNodeSocketValueFloat>()->value;
+
+  const float *subsurface_radius = node->input_by_identifier("Subsurface Radius")
+                                       .default_value_typed<bNodeSocketValueVector>()
+                                       ->value;
+  const float *subsurface_color = node->input_by_identifier("Subsurface Color")
+                                      .default_value_typed<bNodeSocketValueRGBA>()
+                                      ->value;
+  const float metallic =
+      node->input_by_identifier("Metallic").default_value_typed<bNodeSocketValueFloat>()->value;
+  const float specular =
+      node->input_by_identifier("Specular").default_value_typed<bNodeSocketValueFloat>()->value;
+  const float roughness =
+      node->input_by_identifier("Roughness").default_value_typed<bNodeSocketValueFloat>()->value;
+  const float anisotropic =
+      node->input_by_identifier("Anisotropic").default_value_typed<bNodeSocketValueFloat>()->value;
+  const float anisotropic_rot = node->input_by_identifier("Anisotropic Rotation")
+                                    .default_value_typed<bNodeSocketValueFloat>()
+                                    ->value;
+  const float sheen =
+      node->input_by_identifier("Sheen").default_value_typed<bNodeSocketValueFloat>()->value;
+  const float clearcoat =
+      node->input_by_identifier("Clearcoat").default_value_typed<bNodeSocketValueFloat>()->value;
+  const float clearcoat_roughness = node->input_by_identifier("Clearcoat Roughness")
+                                        .default_value_typed<bNodeSocketValueFloat>()
+                                        ->value;
+  const float IOR =
+      node->input_by_identifier("IOR").default_value_typed<bNodeSocketValueFloat>()->value;
+  const float transmission = node->input_by_identifier("Transmission")
+                                 .default_value_typed<bNodeSocketValueFloat>()
+                                 ->value;
+  const float *emission =
+      node->input_by_identifier("Emission").default_value_typed<bNodeSocketValueRGBA>()->value;
+  const float emission_str = node->input_by_identifier("Emission Strength")
+                                 .default_value_typed<bNodeSocketValueFloat>()
+                                 ->value;
+  const float *normal =
+      node->input_by_identifier("Normal").default_value_typed<bNodeSocketValueVector>()->value;
+  const float *clearcoat_normal = node->input_by_identifier("Clearcoat Normal")
+                                      .default_value_typed<bNodeSocketValueVector>()
+                                      ->value;
+  const float *tangent =
+      node->input_by_identifier("Tangent").default_value_typed<bNodeSocketValueVector>()->value;
+#pragma endregion get inputs
+
+#pragma region set inputs
+  matx_node->addInput("base", "float")->setValue(1.0);
+  matx_node->addInput("base_color", "color3")
+      ->setValue(MaterialX::Color3(base_color[0], base_color[1], base_color[2]));
+  matx_node->addInput("diffuse_roughness", "float")->setValue(roughness);
+  matx_node->addInput("normal", "vector3")
+      ->setValue(MaterialX::Vector3(normal[0], normal[1], normal[2]));
+  matx_node->addInput("tangent", "vector3")
+      ->setValue(MaterialX::Vector3(tangent[0], tangent[1], tangent[2]));
+
+  matx_node->addInput("metalness", "float")->setValue(metallic);
+
+  matx_node->addInput("specular", "float")->setValue(specular);
+  matx_node->addInput("specular_color", "color3")->setValue(default_white_color_);
+  matx_node->addInput("specular_roughness", "float")->setValue(roughness);
+  matx_node->addInput("specular_IOR", "float")->setValue(IOR);
+  matx_node->addInput("specular_anisotropy", "float")->setValue(anisotropic);
+  matx_node->addInput("specular_rotation", "float")->setValue(anisotropic_rot);
+
+  matx_node->addInput("transmission", "float")->setValue(transmission);
+  matx_node->addInput("transmission_color", "color3")->setValue(default_white_color_);
+  matx_node->addInput("transmission_extra_roughness", "float")->setValue(roughness);
+
+  matx_node->addInput("subsurface", "float")->setValue(subsurface);
+  matx_node->addInput("subsurface_color", "color3")
+      ->setValue(MaterialX::Color3(subsurface_color[0], subsurface_color[1], subsurface_color[2]));
+  matx_node->addInput("subsurface_radius", "color3")
+      ->setValue(
+          MaterialX::Color3(subsurface_radius[0], subsurface_radius[1], subsurface_radius[2]));
+  matx_node->addInput("subsurface_anisotropy", "float")->setValue(anisotropic);
+
+  matx_node->addInput("sheen", "float")->setValue(sheen);
+  matx_node->addInput("sheen_color", "color3")->setValue(default_white_color_);
+  matx_node->addInput("sheen_roughness", "float")->setValue(roughness);
+
+  matx_node->addInput("coat", "float")->setValue(clearcoat);
+  matx_node->addInput("coat_color", "color3")->setValue(default_white_color_);
+  matx_node->addInput("coat_roughness", "float")->setValue(clearcoat_roughness);
+  matx_node->addInput("coat_IOR", "float")->setValue(IOR);
+  matx_node->addInput("coat_anisotropy", "float")->setValue(anisotropic);
+  matx_node->addInput("coat_rotation", "float")->setValue(anisotropic_rot);
+  matx_node->addInput("coat_normal", "vector3")
+      ->setValue(
+          MaterialX::Vector3(clearcoat_normal[0], clearcoat_normal[1], clearcoat_normal[2]));
+
+  matx_node->addInput("emission", "float")->setValue(emission_str);
+  matx_node->addInput("emission_color", "color3")
+      ->setValue(MaterialX::Color3(emission[0], emission[1], emission[2]));
+#pragma endregion set inputs
+  return matx_node;
+}
+
+}  // namespace blender::nodes::materialx

source/blender/nodes/shader/materialx/nodes/principled_bsdf.h

@@ -0,0 +1,23 @@
+/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later */
+
+#pragma once
+
+#include "node.h"
+
+namespace blender::nodes::materialx {
+
+class MaterialXPrincipledBSDFNode : public MaterialXNode {
+ protected:
+  static const MaterialX::Color3 default_white_color_;
+
+ public:
+  MaterialXPrincipledBSDFNode(MaterialX::DocumentPtr doc,
+                              const Depsgraph *depsgraph,
+                              const Material *material,
+                              const bNode *node);
+  MaterialX::NodePtr convert() override;
+};
+
+}  // namespace blender::nodes::materialx