source/blender/render/hydra/engine.cc

@@ -43,8 +43,6 @@ Engine::Engine(RenderEngine *bl_engine, const std::string &render_delegate_name)
   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"));
-  scene_delegate_ = std::make_unique<BlenderSceneDelegate>(
-      render_index_.get(), pxr::SdfPath::AbsoluteRootPath().AppendElementString("scene"), this);
   render_task_delegate_ = std::make_unique<RenderTaskDelegate>(
       render_index_.get(), pxr::SdfPath::AbsoluteRootPath().AppendElementString("renderTask"));
   if (render_delegate_name == "HdStormRendererPlugin") {
@@ -58,9 +56,22 @@ Engine::Engine(RenderEngine *bl_engine, const std::string &render_delegate_name)
 
 void Engine::sync(Depsgraph *depsgraph, bContext *context)
 {
+  if (!scene_delegate_) {
+    scene_delegate_ = std::make_unique<BlenderSceneDelegate>(
+        render_index_.get(), pxr::SdfPath::AbsoluteRootPath().AppendElementString("scene"), this);
+  }
   scene_delegate_->populate(depsgraph, context);
 }
 
+void Engine::sync_usd(pxr::UsdStageRefPtr stage)
+{
+  if (!usd_delegate_) {
+    usd_delegate_ = std::make_unique<pxr::UsdImagingDelegate>(
+        render_index_.get(), pxr::SdfPath::AbsoluteRootPath().AppendElementString("usd"));
+  }
+  usd_delegate_->Populate(stage->GetPseudoRoot());
+}
+
 void Engine::set_sync_setting(const std::string &key, const pxr::VtValue &val)
 {
   scene_delegate_->set_setting(key, val);

source/blender/render/hydra/engine.h

@@ -9,6 +9,8 @@
 #include <pxr/imaging/hd/engine.h>
 #include <pxr/imaging/hd/pluginRenderDelegateUniqueHandle.h>
 #include <pxr/imaging/hdx/freeCameraSceneDelegate.h>
+#include <pxr/usdImaging/usdImaging/delegate.h>
+#include <pxr/usd/usd/stage.h>
 #include <pxr/imaging/hgi/hgi.h>
 
 #include "RE_engine.h"
@@ -29,6 +31,7 @@ class Engine {
   virtual ~Engine() = default;
 
   void sync(Depsgraph *depsgraph, bContext *context);
+  void sync_usd(pxr::UsdStageRefPtr stage);
   virtual void render(Depsgraph *depsgraph) = 0;
 
   void set_sync_setting(const std::string &key, const pxr::VtValue &val);
@@ -50,6 +53,7 @@ class Engine {
   std::unique_ptr<RenderTaskDelegate> render_task_delegate_;
   std::unique_ptr<pxr::HdxFreeCameraSceneDelegate> free_camera_delegate_;
   std::unique_ptr<SimpleLightTaskDelegate> simple_light_task_delegate_;
+  std::unique_ptr<pxr::UsdImagingDelegate> usd_delegate_;
   std::unique_ptr<pxr::HdEngine> engine_;
 };
 

source/blender/render/hydra/python.cc

@@ -3,9 +3,12 @@
 
 #include <Python.h>
 
+#include <boost/python/extract.hpp>
+
 #include <pxr/base/plug/plugin.h>
 #include <pxr/base/plug/registry.h>
 #include <pxr/usdImaging/usdImagingGL/engine.h>
+#include <pxr/usd/usd/stage.h>
 
 #include "BKE_appdir.h"
 #include "BLI_fileops.h"
@@ -96,6 +99,21 @@ static PyObject *get_render_plugins_func(PyObject * /*self*/, PyObject *args)
   return ret;
 }
 
+static PyObject *test_func(PyObject * /*self*/, PyObject *args)
+{
+  PyObject *pystage;
+  if (!PyArg_ParseTuple(args, "O", &pystage)) {
+    Py_RETURN_NONE;
+  }
+
+  boost::python::extract<pxr::UsdStageRefPtr> e(pystage);
+  pxr::UsdStagePtr stage = e();
+  std::string str;
+  stage->ExportToString(&str);
+  printf("%s", str.c_str());
+  Py_RETURN_NONE;
+}
+
 static PyObject *engine_create_func(PyObject * /*self*/, PyObject *args)
 {
   PyObject *pyengine;
@@ -163,6 +181,24 @@ static PyObject *engine_sync_func(PyObject * /*self*/, PyObject *args)
   Py_RETURN_NONE;
 }
 
+static PyObject *engine_sync_usd_func(PyObject * /*self*/, PyObject *args)
+{
+  PyObject *pyengine, *pystage;
+  if (!PyArg_ParseTuple(args, "OO", &pyengine, &pystage)) {
+    Py_RETURN_NONE;
+  }
+
+  Engine *engine = (Engine *)PyLong_AsVoidPtr(pyengine);
+
+  boost::python::extract<pxr::UsdStageRefPtr> extract(pystage);
+  pxr::UsdStagePtr stage = extract();
+
+  engine->sync_usd(stage);
+
+  CLOG_INFO(LOG_RENDER_HYDRA, 2, "Engine %016llx", engine);
+  Py_RETURN_NONE;
+}
+
 static PyObject *engine_render_func(PyObject * /*self*/, PyObject *args)
 {
   PyObject *pyengine, *pydepsgraph;
@@ -255,10 +291,12 @@ static PyMethodDef methods[] = {
     {"init", init_func, METH_VARARGS, ""},
     {"register_plugins", register_plugins_func, METH_VARARGS, ""},
     {"get_render_plugins", get_render_plugins_func, METH_VARARGS, ""},
+    {"test", test_func, METH_VARARGS, ""},
 
     {"engine_create", engine_create_func, METH_VARARGS, ""},
     {"engine_free", engine_free_func, METH_VARARGS, ""},
     {"engine_sync", engine_sync_func, METH_VARARGS, ""},
+    {"engine_sync_usd", engine_sync_usd_func, METH_VARARGS, ""},
     {"engine_render", engine_render_func, METH_VARARGS, ""},
     {"engine_view_draw", engine_view_draw_func, METH_VARARGS, ""},
     {"engine_set_sync_setting", engine_set_sync_setting_func, METH_VARARGS, ""},