scripts/modules/bpy_hydra.py

@@ -19,7 +19,7 @@ class CustomHydraRenderEngine(HydraRenderEngine):
     def register(cls):
         super().register()
 
-        bpy_hydra.register_plugins(["/path/to/plugin")], ["/additional/system/path")])
+        bpy_hydra.register_plugins(["/path/to/plugin")])
 
     def get_delegate_settings(self, engine_type):
         return {
@@ -58,6 +58,7 @@ class HydraRenderEngine(bpy.types.RenderEngine):
             return
 
         _bpy_hydra.engine_free(self.engine_ptr)
+        del self.engine_ptr
 
     @classmethod
     def register(cls):
@@ -74,20 +75,18 @@ class HydraRenderEngine(bpy.types.RenderEngine):
 
     # final render
     def update(self, data, depsgraph):
-        pass
-
-    def render(self, depsgraph):
         engine_type = 'PREVIEW' if self.is_preview else 'FINAL'
-
         self.engine_ptr = _bpy_hydra.engine_create(self.as_pointer(), engine_type, self.delegate_id)
         delegate_settings = self.get_delegate_settings(engine_type)
-
         _bpy_hydra.engine_sync(self.engine_ptr, depsgraph.as_pointer(), bpy.context.as_pointer(), delegate_settings)
-        _bpy_hydra.engine_render(self.engine_ptr, depsgraph.as_pointer())
+
+    def render(self, depsgraph):
+        if hasattr(self, 'engine_ptr'):
+            _bpy_hydra.engine_render(self.engine_ptr, depsgraph.as_pointer())
 
     # viewport render
     def view_update(self, context, depsgraph):
-        if not self.engine_ptr:
+        if not hasattr(self, 'engine_ptr'):
             self.engine_ptr = _bpy_hydra.engine_create(self.as_pointer(), 'VIEWPORT', self.delegate_id)
 
         delegate_settings = self.get_delegate_settings('VIEWPORT')

source/blender/render/hydra/engine.cc

@@ -42,6 +42,11 @@ Engine::Engine(RenderEngine *bl_engine, const std::string &delegate_id) : bl_eng
   }
 
   engine = std::make_unique<pxr::HdEngine>();
+
+  scene_delegate = std::make_unique<BlenderSceneDelegate>(
+    render_index.get(),
+    pxr::SdfPath::AbsoluteRootPath().AppendElementString("scene"),
+    BlenderSceneDelegate::EngineType::PREVIEW);
 }
 
 Engine::~Engine()
@@ -54,6 +59,7 @@ Engine::~Engine()
   render_delegate = nullptr;
   engine = nullptr;
   hgi = nullptr;
+  bl_engine = nullptr;
 }
 
 float Engine::renderer_percent_done()

source/blender/render/hydra/engine.h

@@ -34,12 +34,12 @@ class Engine {
                     bContext *context,
                     pxr::HdRenderSettingsMap &render_settings) = 0;
   virtual void render(Depsgraph *depsgraph) = 0;
-
+  RenderEngine *bl_engine;
  protected:
   float renderer_percent_done();
 
  protected:
-  RenderEngine *bl_engine;
+  
 
   pxr::HdPluginRenderDelegateUniqueHandle render_delegate;
   std::unique_ptr<pxr::HdRenderIndex> render_index;

source/blender/render/hydra/final_engine.cc

@@ -16,10 +16,6 @@ void FinalEngine::sync(Depsgraph *depsgraph,
                        bContext *context,
                        pxr::HdRenderSettingsMap &render_settings)
 {
-  scene_delegate = std::make_unique<BlenderSceneDelegate>(
-      render_index.get(),
-      pxr::SdfPath::AbsoluteRootPath().AppendElementString("scene"),
-      BlenderSceneDelegate::EngineType::FINAL);
   scene_delegate->populate(depsgraph, context);
 
   for (auto const &setting : render_settings) {

source/blender/render/hydra/preview_engine.cc

@@ -12,19 +12,37 @@ void PreviewEngine::sync(Depsgraph *depsgraph,
                          bContext *context,
                          pxr::HdRenderSettingsMap &render_settings)
 {
-  scene_delegate = std::make_unique<BlenderSceneDelegate>(
-      render_index.get(),
-      pxr::SdfPath::AbsoluteRootPath().AppendElementString("scene"),
-      BlenderSceneDelegate::EngineType::PREVIEW);
+  is_synced = false;
+
+  scene_delegate->clear_data();
+  for (auto &prim : render_index->GetRprimIds()) {
+    render_index->RemoveRprim(prim);
+    render_index->RemoveInstancer(prim);
+    std::cout << "sync RemoveRprim: " << prim.GetText() << " " << render_index->HasRprim(prim)
+              << "\n";
+  }
+
+  for (auto &prim : render_index->GetRprimIds()) {
+    std::cout << "sync after Remove: " << prim.GetText() << "\n";
+  }
+
   scene_delegate->populate(depsgraph, context);
 
+  for (auto &prim : render_index->GetRprimIds()) {
+    std::cout << "sync populate: " << prim.GetText() << "\n";
+  }
+
   for (auto const &setting : render_settings) {
     render_delegate->SetRenderSetting(setting.first, setting.second);
   }
+  is_synced = true;
 }
 
 void PreviewEngine::render(Depsgraph *depsgraph)
 {
+  //if (!is_synced) {
+  //  return;
+  //}
   Scene *scene = DEG_get_input_scene(depsgraph);
   ViewLayer *view_layer = DEG_get_input_view_layer(depsgraph);
 
@@ -35,6 +53,7 @@ void PreviewEngine::render(Depsgraph *depsgraph)
       CameraData(scene->camera, res, pxr::GfVec4f(0, 0, 1, 1)).gf_camera(pxr::GfVec4f(0, 0, 1, 1));
 
   free_camera_delegate->SetCamera(camera);
+  //render_task_delegate->clear_renderer_aovs();
   render_task_delegate->set_camera_and_viewport(free_camera_delegate->GetCameraId(),
                                                 pxr::GfVec4d(0, 0, res[0], res[1]));
   render_task_delegate->set_renderer_aov(pxr::HdAovTokens->color);
@@ -70,6 +89,13 @@ void PreviewEngine::render(Depsgraph *depsgraph)
   update_render_result(layer_name, res[0], res[1], pixels);
 }
 
+void PreviewEngine::stop_renderer()
+{
+  if (render_delegate) {
+    render_delegate->Stop();
+  }
+}
+
 void PreviewEngine::update_render_result(const std::string &layer_name,
                                          int width,
                                          int height,

source/blender/render/hydra/preview_engine.h

@@ -14,6 +14,9 @@ class PreviewEngine : public FinalEngine {
             bContext *context,
             pxr::HdRenderSettingsMap &render_settings) override;
   void render(Depsgraph *depsgraph) override;
+  void stop_renderer();
+
+  bool is_synced = false;
 
  protected:
   void update_render_result(const std::string &layer_name,

source/blender/render/hydra/python.cc

@@ -16,8 +16,25 @@
 #include "utils.h"
 #include "viewport_engine.h"
 
+#include "BLI_timer.h"
+
 namespace blender::render::hydra {
 
+static double preview_engine_lifetime = 60.0;
+static PreviewEngine *preview_engine;
+
+double timer_func(uintptr_t uuid, void *user_data)
+{
+  if (preview_engine) {
+    preview_engine->stop_renderer();
+    delete preview_engine;
+    preview_engine = nullptr;
+    return -1;
+  }
+
+  return preview_engine_lifetime;
+}
+
 static PyObject *init_func(PyObject * /*self*/, PyObject *args)
 {
   CLOG_INFO(LOG_EN, 1, "Init");
@@ -106,14 +123,22 @@ static PyObject *engine_create_func(PyObject * /*self*/, PyObject *args)
   }
 
   RenderEngine *bl_engine = (RenderEngine *)PyLong_AsVoidPtr(pyengine);
-  
 
   Engine *engine;
   if (STREQ(engine_type, "VIEWPORT")) {
     engine = new ViewportEngine(bl_engine, render_delegate_id);
   }
   else if (STREQ(engine_type, "PREVIEW")) {
-    engine = new PreviewEngine(bl_engine, render_delegate_id);
+    if (!preview_engine) {
+      preview_engine = new PreviewEngine(bl_engine, render_delegate_id);
+    }
+    if (BLI_timer_is_registered(1)) {
+      BLI_timer_unregister(1);
+    }
+    preview_engine->bl_engine = bl_engine;
+
+    CLOG_INFO(LOG_EN, 2, "Engine %016llx %s", engine, engine_type);
+    return PyLong_FromVoidPtr(preview_engine);
   }
   else {
     if (bl_engine->type->flag & RE_USE_GPU_CONTEXT) {
@@ -136,7 +161,13 @@ static PyObject *engine_free_func(PyObject * /*self*/, PyObject *args)
     Py_RETURN_NONE;
   }
 
-  Engine *engine = (Engine *) PyLong_AsVoidPtr(pyengine);
+  Engine *engine = (Engine *)PyLong_AsVoidPtr(pyengine);
+
+  if (preview_engine) {
+    BLI_timer_register(1, timer_func, nullptr, nullptr, preview_engine_lifetime, true);
+    Py_RETURN_NONE;
+  }
+
   delete engine;
 
   CLOG_INFO(LOG_EN, 2, "Engine %016llx", engine);

source/blender/render/hydra/render_task_delegate.cc

@@ -132,4 +132,13 @@ void RenderTaskDelegate::set_camera_and_viewport(pxr::SdfPath const &camera_id,
   }
 }
 
+void RenderTaskDelegate::clear_renderer_aovs()
+{
+  for (pxr::HdRenderPassAovBinding &binding : task_params.aovBindings) {
+    std::cout << "clear_renderer_aovs: " << binding.renderBufferId.GetText() << "\n";
+    GetRenderIndex().RemoveBprim(pxr::HdPrimTypeTokens->renderBuffer, binding.renderBufferId);
+    buffer_descriptors.erase(binding.renderBufferId);
+  }
+}
+
 }  // namespace blender::render::hydra

source/blender/render/hydra/render_task_delegate.h

@@ -27,6 +27,7 @@ class RenderTaskDelegate : public pxr::HdSceneDelegate {
 
   pxr::HdTaskSharedPtr get_task();
   void set_camera_and_viewport(pxr::SdfPath const &cameraId, pxr::GfVec4d const &viewport);
+  void clear_renderer_aovs();
 
  private:
   pxr::HdxRenderTaskParams task_params;

source/blender/render/hydra/scene_delegate/blender_scene_delegate.cc

@@ -477,4 +477,10 @@ pxr::VtValue BlenderSceneDelegate::GetLightParamValue(pxr::SdfPath const &id,
   return pxr::VtValue();
 }
 
+void BlenderSceneDelegate::clear_data()
+{
+  objects.clear();
+  materials.clear();
+}
+
 }  // namespace blender::render::hydra

source/blender/render/hydra/scene_delegate/blender_scene_delegate.h

@@ -29,6 +29,7 @@ class BlenderSceneDelegate : public pxr::HdSceneDelegate {
   ~BlenderSceneDelegate() override = default;
 
   void populate(Depsgraph *depsgraph, bContext *context);
+  void clear_data();
 
   // delegate methods
   pxr::HdMeshTopology GetMeshTopology(pxr::SdfPath const &id) override;

source/blender/render/hydra/viewport_engine.cc

@@ -244,12 +244,6 @@ void ViewportEngine::sync(Depsgraph *depsgraph,
                           bContext *context,
                           pxr::HdRenderSettingsMap &render_settings)
 {
-  if (!scene_delegate) {
-    scene_delegate = std::make_unique<BlenderSceneDelegate>(
-        render_index.get(),
-        pxr::SdfPath::AbsoluteRootPath().AppendElementString("scene"),
-        BlenderSceneDelegate::EngineType::VIEWPORT);
-  }
   scene_delegate->populate(depsgraph, context);
 
   for (auto const &setting : render_settings) {