source/blender/render/hydra/engine.cc

@@ -71,7 +71,7 @@ void Engine::sync(Depsgraph *depsgraph, bContext *context)
     if (!hydra_scene_delegate_) {
       pxr::SdfPath scene_path = pxr::SdfPath::AbsoluteRootPath().AppendElementString("scene");
       hydra_scene_delegate_ = std::make_unique<BlenderSceneDelegate>(
-          render_index_.get(), scene_path, scene_delegate_settings_);
+          render_index_.get(), scene_path, scene_delegate_settings);
     }
     hydra_scene_delegate_->populate(depsgraph, context);
   }
@@ -86,7 +86,7 @@ void Engine::sync(Depsgraph *depsgraph, bContext *context)
     if (!usd_scene_delegate_) {
       pxr::SdfPath scene_path = pxr::SdfPath::AbsoluteRootPath().AppendElementString("usd_scene");
       usd_scene_delegate_ = std::make_unique<USDSceneDelegate>(
-          render_index_.get(), scene_path, scene_delegate_settings_);
+          render_index_.get(), scene_path, scene_delegate_settings);
     }
     usd_scene_delegate_->populate(depsgraph, context);
   }
@@ -95,10 +95,10 @@ void Engine::sync(Depsgraph *depsgraph, bContext *context)
 void Engine::set_sync_setting(const std::string &key, const pxr::VtValue &val)
 {
   if (key == "MaterialXFilenameKey") {
-    scene_delegate_settings_.mx_filename_key = pxr::TfToken(val.Get<std::string>());
+    scene_delegate_settings.mx_filename_key = pxr::TfToken(val.Get<std::string>());
   }
   else {
-    scene_delegate_settings_.render_tokens.add_overwrite(pxr::TfToken(key), val);
+    scene_delegate_settings.render_tokens.add_overwrite(pxr::TfToken(key), val);
   }
 }
 

source/blender/render/hydra/engine.h

@@ -39,6 +39,7 @@ class Engine {
   void set_render_setting(const std::string &key, const pxr::VtValue &val);
 
   std::string render_delegate_name;
+  SceneDelegateSettings scene_delegate_settings;
 
  protected:
   float renderer_percent_done();
@@ -51,7 +52,6 @@ class Engine {
   pxr::HdPluginRenderDelegateUniqueHandle render_delegate_;
   std::unique_ptr<pxr::HdRenderIndex> render_index_;
 
-  SceneDelegateSettings scene_delegate_settings_;
   std::unique_ptr<BlenderSceneDelegate> hydra_scene_delegate_;
   std::unique_ptr<USDSceneDelegate> usd_scene_delegate_;
 

source/blender/render/hydra/final_engine.cc

@@ -109,7 +109,7 @@ void FinalEngine::prepare_for_render(Depsgraph *depsgraph)
   if (light_tasks_delegate_) {
     light_tasks_delegate_->set_camera_and_viewport(
         free_camera_delegate_->GetCameraId(), pxr::GfVec4d(0, 0, resolution_[0], resolution_[1]));
-    tasks_ = light_tasks_delegate_->get_tasks();
+    tasks_ = light_tasks_delegate_->get_tasks(scene_delegate_settings);
   }
   tasks_.push_back(render_task_delegate_->get_task());
 

source/blender/render/hydra/light_tasks_delegate.cc

@@ -1,6 +1,7 @@
 /* SPDX-License-Identifier: Apache-2.0
  * Copyright 2011-2022 Blender Foundation */
 
+#include "BLI_map.hh"
 #include <pxr/imaging/hdx/simpleLightTask.h>
 #include <pxr/imaging/hdx/skydomeTask.h>
 
@@ -18,12 +19,18 @@ LightTasksDelegate::LightTasksDelegate(pxr::HdRenderIndex *parent_index,
   GetRenderIndex().InsertTask<pxr::HdxSimpleLightTask>(this, simple_task_id_);
 }
 
-pxr::HdTaskSharedPtrVector LightTasksDelegate::get_tasks()
+pxr::HdTaskSharedPtrVector LightTasksDelegate::get_tasks(const SceneDelegateSettings &settings)
 {
   /*Note that this task is intended to be the first "Render Task",
   so that the AOV's are properly cleared, however it
   does not spawn a HdRenderPass.*/
-  return {GetRenderIndex().GetTask(skydome_task_id_), GetRenderIndex().GetTask(simple_task_id_)};
+  pxr::HdTaskSharedPtrVector tasks;
+  const pxr::VtValue *ret_ptr = settings.render_tokens.lookup_ptr(pxr::TfToken("enableAlpha"));
+  if (ret_ptr->Get<bool>()) {
+    tasks.push_back(GetRenderIndex().GetTask(skydome_task_id_));
+  }
+  tasks.push_back(GetRenderIndex().GetTask(simple_task_id_));
+  return tasks;
 }
 
 void LightTasksDelegate::set_camera_and_viewport(pxr::SdfPath const &camera_id,

source/blender/render/hydra/light_tasks_delegate.h

@@ -3,6 +3,8 @@
 
 #pragma once
 
+#include "scene_delegate/blender_scene_delegate.h"
+#include "scene_delegate/usd_scene_delegate.hh"
 #include <pxr/imaging/hd/sceneDelegate.h>
 #include <pxr/imaging/hdx/renderSetupTask.h>
 #include <pxr/imaging/hdx/simpleLightTask.h>
@@ -14,7 +16,7 @@ class LightTasksDelegate : public pxr::HdSceneDelegate {
   LightTasksDelegate(pxr::HdRenderIndex *parentIndex, pxr::SdfPath const &delegate_id);
   ~LightTasksDelegate() override = default;
 
-  pxr::HdTaskSharedPtrVector get_tasks();
+  pxr::HdTaskSharedPtrVector get_tasks(const SceneDelegateSettings &settings);
   void set_camera_and_viewport(pxr::SdfPath const &camera_id, pxr::GfVec4d const &viewport);
 
   /* Delegate methods */

source/blender/render/hydra/viewport_engine.cc

@@ -254,7 +254,7 @@ void ViewportEngine::render(Depsgraph * /* depsgraph */, bContext *context)
 
   pxr::HdTaskSharedPtrVector tasks;
   if (light_tasks_delegate_) {
-    tasks = light_tasks_delegate_->get_tasks();
+    tasks = light_tasks_delegate_->get_tasks(scene_delegate_settings);
   }
   tasks.push_back(render_task_delegate_->get_task());