source/blender/blenkernel/BKE_node.h

@@ -225,6 +225,9 @@ typedef int (*NodeGPUExecFunction)(struct GPUMaterial *mat,
                                    struct bNodeExecData *execdata,
                                    struct GPUNodeStack *in,
                                    struct GPUNodeStack *out);
+typedef void (*NodeMaterialXExecFunction)(void *data,
+                                          struct bNode *node,
+                                          struct bNodeSocket *out);
 
 /**
  * \brief Defines a node type.
@@ -339,6 +342,8 @@ typedef struct bNodeType {
   NodeExecFunction exec_fn;
   /* gpu */
   NodeGPUExecFunction gpu_fn;
+  /* MaterialX */
+  NodeMaterialXExecFunction materialx_fn;
 
   /* Get an instance of this node's compositor operation. Freeing the instance is the
    * responsibility of the caller. */

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

@@ -125,4 +125,37 @@ DECLARE_SHADER_NODE_PARSER(EmissionNodeParser)
 DECLARE_SHADER_NODE_PARSER(MixShaderNodeParser)
 DECLARE_SHADER_NODE_PARSER(SubsurfaceScatteringNodeParser)
 
+
+struct NodeParserData {
+  MaterialX::GraphElement *graph;
+  const Depsgraph *depsgraph;
+  const Material *material;
+  NodeItem result;
+};
+
+template<class T>
+void node_shader_materialx(void *data, struct bNode *node, struct bNodeSocket *out)
+{
+  materialx::NodeParserData *d = reinterpret_cast<materialx::NodeParserData *>(data);
+  T parser(d->graph, d->depsgraph, d->material, node, out);
+  d->result = parser.compute();
+}
+
+#define NODE_SHADER_MATERIALX_BEGIN \
+class MaterialXNodeParser : public materialx::NodeParser { \
+ public: \
+  using materialx::NodeParser::NodeParser; \
+  materialx::NodeItem compute() override \
+  { \
+    using NodeItem = materialx::NodeItem;
+
+#define NODE_SHADER_MATERIALX_END \
+  } \
+}; \
+\
+void node_shader_materialx(void *data, struct bNode *node, struct bNodeSocket *out) \
+{ \
+  materialx::node_shader_materialx<MaterialXNodeParser>(data, node, out); \
+}
+
 }  // namespace blender::nodes::materialx

source/blender/nodes/shader/nodes/node_shader_bsdf_principled.cc

@@ -5,6 +5,7 @@
 #include "BLI_string.h"
 
 #include "node_shader_util.hh"
+#include "../materialx/nodes/node_parser.h"
 
 #include "UI_interface.hh"
 #include "UI_resources.hh"
@@ -253,6 +254,12 @@ static void node_shader_update_principled(bNodeTree *ntree, bNode *node)
   }
 }
 
+NODE_SHADER_MATERIALX_BEGIN
+{
+  return empty();
+}
+NODE_SHADER_MATERIALX_END
+
 }  // namespace blender::nodes::node_shader_bsdf_principled_cc
 
 /* node type definition */
@@ -270,6 +277,7 @@ void register_node_type_sh_bsdf_principled()
   ntype.initfunc = file_ns::node_shader_init_principled;
   ntype.gpu_fn = file_ns::node_shader_gpu_bsdf_principled;
   ntype.updatefunc = file_ns::node_shader_update_principled;
+  ntype.materialx_fn = file_ns::node_shader_materialx;
 
   nodeRegisterType(&ntype);
 }

source/blender/nodes/shader/nodes/node_shader_output_material.cc

@@ -3,6 +3,7 @@
  * SPDX-License-Identifier: GPL-2.0-or-later */
 
 #include "node_shader_util.hh"
+#include "../materialx/nodes/node_parser.h"
 
 #include "BKE_scene.h"
 
@@ -43,6 +44,33 @@ static int node_shader_gpu_output_material(GPUMaterial *mat,
   return true;
 }
 
+NODE_SHADER_MATERIALX_BEGIN
+  NodeItem surface = empty();
+  if (node_) {
+    NodeItem bsdf = get_input_shader("Surface", NodeItem::Type::BSDF);
+    NodeItem edf = get_input_shader("Surface", NodeItem::Type::EDF);
+    if (bsdf || edf) {
+      surface = create_node("surface", NodeItem::Type::SurfaceShader);
+      if (bsdf) {
+        surface.set_input("bsdf", bsdf);
+      }
+      if (edf) {
+        surface.set_input("edf", edf);
+      }
+    }
+    else {
+      surface = get_input_shader("Surface", NodeItem::Type::SurfaceShader);
+    }
+  }
+  else {
+    surface = create_node("standard_surface", NodeItem::Type::SurfaceShader);
+    surface.set_input("base_color", val(MaterialX::Color3(1.0f, 0.0f, 1.0f)));
+  }
+  NodeItem res = create_node("surfacematerial", NodeItem::Type::Material);
+  res.set_input("surfaceshader", surface);
+  return res;
+NODE_SHADER_MATERIALX_END
+
 }  // namespace blender::nodes::node_shader_output_material_cc
 
 /* node type definition */
@@ -56,6 +84,7 @@ void register_node_type_sh_output_material()
   ntype.declare = file_ns::node_declare;
   ntype.add_ui_poll = object_shader_nodes_poll;
   ntype.gpu_fn = file_ns::node_shader_gpu_output_material;
+  ntype.materialx_fn = file_ns::node_shader_materialx;
 
   ntype.no_muting = true;