[Bf-blender-cvs] [013d758cb7c] cycles_path_guiding: Fix broken training, train_guiding was not propagated to CPU threads

[Brecht Van Lommel]

Commit: 013d758cb7c0394a298e6566e964aaaa01864c22
Author: Brecht Van Lommel
Date:   Mon Sep 19 20:52:52 2022 +0200
Branches: cycles_path_guiding
https://developer.blender.org/rB013d758cb7c0394a298e6566e964aaaa01864c22

Fix broken training, train_guiding was not propagated to CPU threads

===================================================================

M	intern/cycles/integrator/path_trace.cpp
M	intern/cycles/integrator/path_trace_work.h
M	intern/cycles/integrator/path_trace_work_cpu.cpp
M	intern/cycles/integrator/path_trace_work_cpu.h

===================================================================

diff --git a/intern/cycles/integrator/path_trace.cpp b/intern/cycles/integrator/path_trace.cpp
index 5021a3e18ba..985287bad51 100644
--- a/intern/cycles/integrator/path_trace.cpp
+++ b/intern/cycles/integrator/path_trace.cpp
@@ -1318,23 +1318,23 @@ void PathTrace::set_guiding_params(const GuidingParams &guiding_params, const bo
 void PathTrace::guiding_prepare_structures()
 {
 #ifdef WITH_PATH_GUIDING
+  const bool train = (guiding_params_.training_iterations == -1) ||
+                     (guiding_field_->GetIteration() < guiding_params_.training_iterations);
+
   for (auto &&path_trace_work : path_trace_works_) {
-    path_trace_work->guiding_init_kernel_globals(guiding_field_.get(),
-                                                 guiding_sample_data_storage_.get());
+    path_trace_work->guiding_init_kernel_globals(
+        guiding_field_.get(), guiding_sample_data_storage_.get(), train);
   }
 
-  if ((guiding_params_.training_iterations == -1) ||
-      (guiding_field_->GetIteration() < guiding_params_.training_iterations)) {
+  if (train) {
     /* For training the guiding distribution we need to force the number of samples
      * per update to be limited, for reproducible results and reasonable training size.
      *
      * Idea: we could stochastically discard samples with a probability of 1/num_samples_per_update
      * we can then update only after the num_samples_per_update iterations are rendered.  */
-    device_scene_->data.integrator.train_guiding = true;
     render_scheduler_.set_limit_samples_per_update(4);
   }
   else {
-    device_scene_->data.integrator.train_guiding = false;
     render_scheduler_.set_limit_samples_per_update(0);
   }
 #endif
diff --git a/intern/cycles/integrator/path_trace_work.h b/intern/cycles/integrator/path_trace_work.h
index db419330255..2ffebc14a25 100644
--- a/intern/cycles/integrator/path_trace_work.h
+++ b/intern/cycles/integrator/path_trace_work.h
@@ -145,7 +145,7 @@ class PathTraceWork {
    * global guiding field and the sample data storage as well es initializes the per-thread
    * guided sampling distrubtions (e.g., SurfaceSamplingDistribution and
    * VolumeSamplingDistribution). */
-  virtual void guiding_init_kernel_globals(void *, void *)
+  virtual void guiding_init_kernel_globals(void *, void *, const bool)
   {
   }
 #endif
diff --git a/intern/cycles/integrator/path_trace_work_cpu.cpp b/intern/cycles/integrator/path_trace_work_cpu.cpp
index e212595394c..db697034576 100644
--- a/intern/cycles/integrator/path_trace_work_cpu.cpp
+++ b/intern/cycles/integrator/path_trace_work_cpu.cpp
@@ -57,10 +57,12 @@ void PathTraceWorkCPU::init_execution()
   device_->get_cpu_kernel_thread_globals(kernel_thread_globals_);
 }
 
-#if defined(WITH_PATH_GUIDING)
+#ifdef WITH_PATH_GUIDING
 /* Note: It seems that this is called before every rendering iteration/progression and not once per
  * rendering. May be we find a way to call it only once per rendering. */
-void PathTraceWorkCPU::guiding_init_kernel_globals(void *guiding_field, void *sample_data_storage)
+void PathTraceWorkCPU::guiding_init_kernel_globals(void *guiding_field,
+                                                   void *sample_data_storage,
+                                                   const bool train)
 {
   /* Linking the global guiding structures (e.g., Field and SampleStorage) to the per-thread
    * kernel globals. */
@@ -69,30 +71,29 @@ void PathTraceWorkCPU::guiding_init_kernel_globals(void *guiding_field, void *sa
 #  endif
   for (int thread_index = 0; thread_index < kernel_thread_globals_.size(); thread_index++) {
 #  if PATH_GUIDING_LEVEL >= 3
+    CPUKernelThreadGlobals &kg = kernel_thread_globals_[thread_index];
 
-    kernel_thread_globals_[thread_index].opgl_sample_data_storage = (openpgl::cpp::SampleStorage *)
-        sample_data_storage;
+    kg.opgl_sample_data_storage = (openpgl::cpp::SampleStorage *)sample_data_storage;
 #  endif
 
 #  if PATH_GUIDING_LEVEL >= 4
     if (field) {
-      kernel_thread_globals_[thread_index].opgl_guiding_field = field;
-      if (kernel_thread_globals_[thread_index].opgl_surface_sampling_distribution)
-        delete kernel_thread_globals_[thread_index].opgl_surface_sampling_distribution;
-      kernel_thread_globals_[thread_index].opgl_surface_sampling_distribution =
-          new openpgl::cpp::SurfaceSamplingDistribution(field);
-      if (kernel_thread_globals_[thread_index].opgl_volume_sampling_distribution)
-        delete kernel_thread_globals_[thread_index].opgl_volume_sampling_distribution;
-      kernel_thread_globals_[thread_index].opgl_volume_sampling_distribution =
-          new openpgl::cpp::VolumeSamplingDistribution(field);
+      kg.opgl_guiding_field = field;
+      if (kg.opgl_surface_sampling_distribution)
+        delete kg.opgl_surface_sampling_distribution;
+      kg.opgl_surface_sampling_distribution = new openpgl::cpp::SurfaceSamplingDistribution(field);
+      if (kg.opgl_volume_sampling_distribution)
+        delete kg.opgl_volume_sampling_distribution;
+      kg.opgl_volume_sampling_distribution = new openpgl::cpp::VolumeSamplingDistribution(field);
     }
     else {
-      kernel_thread_globals_[thread_index].opgl_guiding_field = nullptr;
-      kernel_thread_globals_[thread_index].opgl_surface_sampling_distribution = nullptr;
-      kernel_thread_globals_[thread_index].opgl_volume_sampling_distribution = nullptr;
+      kg.opgl_guiding_field = nullptr;
+      kg.opgl_surface_sampling_distribution = nullptr;
+      kg.opgl_volume_sampling_distribution = nullptr;
     }
-
 #  endif
+
+    kg.data.integrator.train_guiding = train;
   }
 }
 #endif
diff --git a/intern/cycles/integrator/path_trace_work_cpu.h b/intern/cycles/integrator/path_trace_work_cpu.h
index 93d14364a4f..5004d2f6a85 100644
--- a/intern/cycles/integrator/path_trace_work_cpu.h
+++ b/intern/cycles/integrator/path_trace_work_cpu.h
@@ -66,7 +66,9 @@ class PathTraceWorkCPU : public PathTraceWork {
    * global guiding field and the sample data storage as well es initializes the per-thread
    * guided sampling distrubtions (e.g., SurfaceSamplingDistribution and
    * VolumeSamplingDistribution). */
-  void guiding_init_kernel_globals(void *guiding_field, void *sample_data_storage) override;
+  void guiding_init_kernel_globals(void *guiding_field,
+                                   void *sample_data_storage,
+                                   const bool train) override;
 #endif
 
  protected: