Fix #114168: EEVEE-Next: Viewport image render sampling

Support sample accumulation in viewport image rendering.

Pull Request: https://projects.blender.org/blender/blender/pulls/116198

source/blender/draw/engines/eevee_next/eevee_engine.cc

@@ -103,8 +103,12 @@ static void eevee_engine_init(void *vedata)
 static void eevee_draw_scene(void *vedata)
 {
   EEVEE_Data *ved = reinterpret_cast<EEVEE_Data *>(vedata);
-  DefaultFramebufferList *dfbl = DRW_viewport_framebuffer_list_get();
-  ved->instance->draw_viewport(dfbl);
+  if (DRW_state_is_viewport_image_render()) {
+    ved->instance->draw_viewport_image_render();
+  }
+  else {
+    ved->instance->draw_viewport();
+  }
   STRNCPY(ved->info, ved->instance->info.c_str());
   /* Reset view for other following engines. */
   DRW_view_set_active(nullptr);

source/blender/draw/engines/eevee_next/eevee_instance.cc

@@ -493,9 +493,8 @@ void Instance::render_frame(RenderLayer *render_layer, const char *view_name)
   this->render_read_result(render_layer, view_name);
 }
 
-void Instance::draw_viewport(DefaultFramebufferList *dfbl)
+void Instance::draw_viewport()
 {
-  UNUSED_VARS(dfbl);
   render_sample();
   velocity.step_swap();
 
@@ -518,6 +517,14 @@ void Instance::draw_viewport(DefaultFramebufferList *dfbl)
   }
 }
 
+void Instance::draw_viewport_image_render()
+{
+  while (!sampling.finished_viewport()) {
+    this->render_sample();
+  }
+  velocity.step_swap();
+}
+
 void Instance::store_metadata(RenderResult *render_result)
 {
   cryptomatte.store_metadata(render_result);

source/blender/draw/engines/eevee_next/eevee_instance.hh

@@ -180,7 +180,8 @@ class Instance {
 
   /* Viewport. */
 
-  void draw_viewport(DefaultFramebufferList *dfbl);
+  void draw_viewport();
+  void draw_viewport_image_render();
 
   /* Light bake. */
 
@@ -199,6 +200,11 @@ class Instance {
     return render == nullptr && !is_baking();
   }
 
+  bool is_viewport_image_render() const
+  {
+    return DRW_state_is_viewport_image_render();
+  }
+
   bool is_baking() const
   {
     return is_light_bake;

source/blender/draw/engines/eevee_next/eevee_sampling.cc

@@ -75,7 +75,8 @@ void Sampling::end_sync()
 
     interactive_mode_ = viewport_sample_ < interactive_mode_threshold;
 
-    bool interactive_mode_disabled = (inst_.scene->eevee.flag & SCE_EEVEE_TAA_REPROJECTION) == 0;
+    bool interactive_mode_disabled = (inst_.scene->eevee.flag & SCE_EEVEE_TAA_REPROJECTION) == 0 ||
+                                     inst_.is_viewport_image_render();
     if (interactive_mode_disabled) {
       interactive_mode_ = false;
       sample_ = viewport_sample_;