Added basic code
Updated addon structure
Fixing libs and build

@@ -794,2 +794,4 @@
 mark_as_advanced(POSTCONFIGURE_SCRIPT)
 
+# USD Hydra plugin.
+if(WIN32 AND WITH_USD AND WITH_MATERIALX)

@@ -902,0 +902,4 @@
+if(WITH_MATERIALX)
+  windows_find_package(MaterialX)
+  if(NOT MaterialX_FOUND)
+    include("${LIBDIR}/MaterialX/lib/cmake/MaterialX/MaterialXTargets.cmake")

@@ -0,0 +3,4 @@
+
+# <pep8 compliant>
+
+import traceback

@@ -0,0 +6,4 @@
+import traceback
+
+import bpy
+import _hydra

@@ -0,0 +11,4 @@
+from _hydra import register_plugins, get_render_plugins
+
+
+class HydraRenderEngine(bpy.types.RenderEngine):

@@ -0,0 +67,4 @@
+    try:
+        import materialx.utils as mx_utils
+
+        material = bpy.data.materials[material_name]

@@ -0,0 +80,4 @@
+        print("ERROR: no MaterialX addon available")
+
+    except Exception as e:
+        print("ERROR:", e, traceback.format_exc())

@@ -0,0 +15,4 @@
+add_definitions(${GFLAGS_DEFINES})
+add_definitions(${GLOG_DEFINES})
+add_definitions(-DGLOG_NO_ABBREVIATED_SEVERITIES)
+add_definitions(-DBLENDER_GFLAGS_NAMESPACE=${GFLAGS_NAMESPACE})

@@ -0,0 +40,4 @@
+    return;
+  }
+
+  set_env_paths("PXR_MTLX_STDLIB_SEARCH_PATHS", {stdlib_path});

@@ -0,0 +85,4 @@
+  }
+
+  if (!path_dirs.empty()) {
+    set_env_paths("PATH", path_dirs);

@@ -0,0 +1,324 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright 2011-2022 Blender Foundation */
+
+#include <epoxy/gl.h>

@@ -982,1 +982,4 @@
       ${LIBDIR}/materialx/bin/MaterialXGenShader.dll
+      ${LIBDIR}/materialx/bin/MaterialXRender.dll
+      ${LIBDIR}/materialx/bin/MaterialXRenderHw.dll
+      ${LIBDIR}/materialx/bin/MaterialXRenderGlsl.dll

@@ -1567,0 +1574,4 @@
+  install(DIRECTORY
+    ${LIBDIR}/usd/plugin/usd/hdStorm
+    ${LIBDIR}/usd/plugin/usd/usdShaders
+    DESTINATION "./blender.shared/usd"

@@ -0,0 +12,4 @@
+
+namespace blender::render::hydra {
+
+CLG_LOGREF_DECLARE_GLOBAL(LOG_EN, "rhd.en");

@@ -0,0 +23,4 @@
+
+  pxr::HdDriverVector hd_drivers;
+  if (bl_engine->type->flag & RE_USE_GPU_CONTEXT) {
+    hgi = pxr::Hgi::CreatePlatformDefaultHgi();

@@ -0,0 +32,4 @@
+
+  render_index.reset(pxr::HdRenderIndex::New(render_delegate.Get(), hd_drivers));
+  free_camera_delegate = std::make_unique<pxr::HdxFreeCameraSceneDelegate>(
+      render_index.get(), pxr::SdfPath::AbsoluteRootPath().AppendElementString("freeCamera"));

@@ -0,0 +35,4 @@
+      render_index.get(), pxr::SdfPath::AbsoluteRootPath().AppendElementString("freeCamera"));
+  render_task_delegate = std::make_unique<RenderTaskDelegate>(
+      render_index.get(), pxr::SdfPath::AbsoluteRootPath().AppendElementString("renderTask"));
+  if (render_delegate->GetRendererDisplayName() == "GL") {

@@ -0,0 +53,4 @@
+  render_index = nullptr;
+  render_delegate = nullptr;
+  engine = nullptr;
+  hgi = nullptr;

@@ -0,0 +5,4 @@
+
+#include <chrono>
+
+#include <Python.h>

@@ -0,0 +30,4 @@
+void FinalEngine::render(Depsgraph *depsgraph)
+{
+  Scene *scene = DEG_get_input_scene(depsgraph);
+  ViewLayer *view_layer = DEG_get_input_view_layer(depsgraph);

@@ -0,0 +36,4 @@
+  BKE_id_full_name_get(scene_name.data(), (ID *)scene, 0);
+  std::string layer_name = view_layer->name;
+
+  RenderData &r = scene->r;

@@ -0,0 +45,4 @@
+                          r.border.ymax - r.border.ymin);
+  }
+  pxr::GfVec2i image_res(r.xsch * r.size / 100, r.ysch * r.size / 100);
+  pxr::GfVec2i res(int(image_res[0] * border[2]), int(image_res[1] * border[3]));

@@ -0,0 +147,4 @@
+  RE_engine_update_stats(bl_engine, title.c_str(), info.c_str());
+}
+
+void FinalEngineGL::render(Depsgraph *depsgraph)

@@ -0,0 +196,4 @@
+  std::vector<float> &pixels = render_images["Combined"];
+
+  GPUFrameBuffer *framebuffer = GPU_framebuffer_create("fbHydraRenderFinal");
+  GPUTexture *texture = GPU_texture_create_2d("texHydraRenderFinal",

@@ -0,0 +18,4 @@
+  instance->render_delegate->Stop();
+
+  /* Register timer for schedule free PreviewEngine instance */
+  BLI_timer_register((uintptr_t)instance.get(),

@@ -0,0 +70,4 @@
+  }
+}
+
+void PreviewEngine::render(Depsgraph *depsgraph)

@@ -0,0 +11,4 @@
+
+namespace blender::render::hydra {
+
+CLG_LOGREF_DECLARE_GLOBAL(LOG_BSD, "rhd.bsd");

@@ -0,0 +20,4 @@
+      engine_type(engine_type),
+      depsgraph(nullptr),
+      context(nullptr),
+      view3d(nullptr)

@@ -0,0 +29,4 @@
+  return ret;
+}
+
+std::string format_duration(std::chrono::milliseconds millisecs)

@@ -0,0 +58,4 @@
+  return ss.str();
+}
+
+std::string cache_image(Main *bmain,

@@ -0,0 +87,4 @@
+
+  image_name.append(default_format);
+
+  BLI_path_join(tempfile, sizeof(tempfile), BKE_tempdir_session(), image_name.c_str());

@@ -0,0 +12,4 @@
+#include "BKE_camera.h"
+#include "BLI_math_matrix.h"
+#include "DEG_depsgraph_query.h"
+#include "GPU_matrix.h"

@@ -0,0 +109,4 @@
+        if not doc:
+            return ""
+
+        mtlx_file = mx_utils.get_temp_file(".mtlx", material.name)

@@ -0,0 +3,4 @@
+
+#pragma once
+
+#include <pxr/imaging/hd/sceneDelegate.h>

@@ -0,0 +40,4 @@
+
+#define ID_LOG(level, msg, ...) \
+  CLOG_INFO( \
+      LOG_RENDER_HYDRA_SCENE, level, "%s (%s): " msg, prim_id.GetText(), id->name, __VA_ARGS__);

@@ -0,0 +246,4 @@
+int InstancerData::light_prim_id_index(pxr::SdfPath const &id) const
+{
+  int index;
+  sscanf_s(id.GetName().c_str(), "L_%x", &index);

@@ -0,0 +8,4 @@
+
+#include <string>
+
+struct pxr::HdMaterialNetworkMap;

@@ -0,0 +42,4 @@
+  instance_->render_delegate_->Stop();
+
+  /* Register timer for schedule free PreviewEngine instance */
+  BLI_timer_register((uintptr_t)&instance_, free_instance, nullptr, nullptr, LIFETIME, true);

@@ -0,0 +21,4 @@
+
+  {
+    /* Release the GIL before calling into hydra, in case any hydra plugins call into python. */
+    pxr::TF_PY_ALLOW_THREADS_IN_SCOPE();

@@ -0,0 +53,4 @@
+
+  {
+    /* Release the GIL before calling into hydra, in case any hydra plugins call into python. */
+    pxr::TF_PY_ALLOW_THREADS_IN_SCOPE();

@@ -0,0 +22,4 @@
+  CLOG_INFO(LOG_RENDER_HYDRA, 1, "Init");
+
+  pxr::PlugRegistry::GetInstance().RegisterPlugins(std::string(BKE_appdir_program_dir()) +
+                                                   "/blender.shared/usd");

@@ -0,0 +366,4 @@
+  pxr::SdfPath id = instancer_prim_id(object);
+  InstancerData *i_data = instancer_data(id);
+  if (i_data) {
+    if ((object->transflag & OB_DUPLI) == 0) {

@@ -0,0 +69,4 @@
+
+pxr::VtValue CurvesData::get_data(pxr::SdfPath const &id, pxr::TfToken const &key) const
+{
+  pxr::VtValue ret;

@@ -0,0 +160,4 @@
+    curve_vertex_counts_.push_back(num_points);
+
+    /* Set radius similar to Cycles if isn't set */
+    widths_.push_back(radii ? radii[i] : 0.01f);

@@ -0,0 +189,4 @@
+  Object *object = (Object *)id;
+  Material *mat = nullptr;
+  if (BKE_object_material_count_eval(object) > 0) {
+    mat = BKE_object_material_get_eval(object, object->actcol);

@@ -0,0 +23,4 @@
+{
+  std::string file_path(FILE_MAX, 0);
+  char file_name[32];
+  snprintf(file_name, 32, "img_%016llx.hdr", (uintptr_t)image);

@@ -0,0 +25,4 @@
+  char file_name[32];
+  snprintf(file_name, 32, "img_%016llx.hdr", (uintptr_t)image);
+  BLI_path_join(file_path.data(),
+                file_path.capacity(),

@@ -0,0 +38,4 @@
+  ImageSaveOptions opts;
+  opts.im_format.imtype = R_IMF_IMTYPE_RADHDR;
+
+  if (BKE_image_save_options_init(&opts, main, scene_delegate->scene, image, iuser, true, false)) {

@@ -0,0 +41,4 @@
+  if (BKE_image_save_options_init(&opts, main, scene_delegate->scene, image, iuser, true, false)) {
+    STRNCPY(opts.filepath, file_path.c_str());
+    ReportList reports;
+    if (!BKE_image_save(&reports, main, image, iuser, &opts)) {

@@ -0,0 +67,4 @@
+    BKE_image_user_file_path_ex(main, iuser, image, file_path.data(), false, true);
+
+    if (!pxr::HioImageRegistry::GetInstance().IsSupportedImageFile(file_path)) {
+      file_path = cache_image_file(image, scene_delegate, iuser, true);

@@ -0,0 +25,4 @@
+    case OB_MESH:
+    case OB_SURF:
+    case OB_FONT:
+    case OB_CURVES_LEGACY:

@@ -0,0 +49,4 @@
+      /* If some of parent object is instancer, then currenct object as instancer
+       * is invisible in Final render */
+      for (Object *ob = object->parent; ob != nullptr; ob = ob->parent) {
+        if (ob->transflag & OB_DUPLI) {

@@ -0,0 +127,4 @@
+    char name[16];
+    for (auto &it : light_instances_) {
+      for (int i = 0; i < it.second.count; ++i) {
+        snprintf(name, 16, "L_%08x", i);

@@ -0,0 +233,4 @@
+    bool do_write_instances = false;
+    ListBase *lb = object_duplilist(
+        scene_delegate_->depsgraph, scene_delegate_->scene, (Object *)id);
+    LISTBASE_FOREACH (DupliObject *, dupli, lb) {

@@ -0,0 +350,4 @@
+    it.second.transforms.clear();
+  }
+
+  ListBase *lb = object_duplilist(

@@ -0,0 +146,4 @@
+  else {
+    std::string n = key.GetString();
+    if (boost::algorithm::contains(n, "object:visibility:")) {
+      if (boost::algorithm::ends_with(n, "camera") || boost::algorithm::ends_with(n, "shadow")) {

@@ -0,0 +112,4 @@
+  std::string path;
+
+  if (!PyErr_Occurred()) {
+    path = PyUnicode_AsUTF8(result);

@@ -0,0 +113,4 @@
+
+  if (!PyErr_Occurred()) {
+    path = PyUnicode_AsUTF8(result);
+    Py_DECREF(result);

@@ -0,0 +27,4 @@
+
+  Object *object = (Object *)id;
+  if (object->type == OB_MESH && object->mode == OB_MODE_OBJECT &&
+      BLI_listbase_is_empty(&object->modifiers))

@@ -0,0 +97,4 @@
+void ObjectData::update_parent()
+{
+  Object *object = (Object *)id;
+  if (parent_ != object->parent) {

@@ -0,0 +83,4 @@
+
+    if (!color_input.directly_linked_links().is_empty()) {
+      bNode *color_input_node = color_input.directly_linked_links()[0]->fromnode;
+      if (color_input_node->type == SH_NODE_TEX_IMAGE) {