Refactor: Make prepare_viewlayer a base render method

Should be no functional changes.

source/blender/render/intern/engine.cc

@@ -849,13 +849,11 @@ static void engine_render_view_layer(Render *re,
   /* Create depsgraph with scene evaluated at render resolution. */
   ViewLayer *view_layer = static_cast<ViewLayer *>(
       BLI_findstring(&re->scene->view_layers, view_layer_iter->name, offsetof(ViewLayer, name)));
-  if (re->prepare_viewlayer_cb) {
-    if (!re->prepare_viewlayer_cb(re->prepare_vl_handle, view_layer, engine->depsgraph)) {
-      if (re->draw_lock_cb) {
-        re->draw_lock_cb(re->dlh, false);
-      }
-      return;
+  if (!re->prepare_viewlayer(view_layer, engine->depsgraph)) {
+    if (re->draw_lock_cb) {
+      re->draw_lock_cb(re->dlh, false);
     }
+    return;
   }
   engine_depsgraph_init(engine, view_layer);
 

source/blender/render/intern/render_types.cc

@@ -40,3 +40,12 @@ Render::~Render()
 
   render_result_free(pushedresult);
 }
+
+bool Render::prepare_viewlayer(struct ViewLayer *view_layer, struct Depsgraph *depsgraph)
+{
+  if (!prepare_viewlayer_cb) {
+    return true;
+  }
+
+  return prepare_viewlayer_cb(prepare_vl_handle, view_layer, depsgraph);
+}

source/blender/render/intern/render_types.h

@@ -49,6 +49,14 @@ struct BaseRender {
                                   const char *view_name) = 0;
   virtual void compositor_free() = 0;
 
+  /**
+   * Executed right before the initialization of the depsgraph, in order to modify some stuff in
+   * the viewlayer. The modified ids must be tagged in the depsgraph.
+   *
+   * If false is returned then rendering is aborted,
+   */
+  virtual bool prepare_viewlayer(struct ViewLayer *view_layer, struct Depsgraph *depsgraph) = 0;
+
   /* Result of rendering */
   RenderResult *result = nullptr;
 
@@ -78,6 +86,12 @@ struct ViewRender : public BaseRender {
   {
   }
   void compositor_free() override {}
+
+  bool prepare_viewlayer(struct ViewLayer * /*view_layer*/,
+                         struct Depsgraph * /*depsgraph*/) override
+  {
+    return true;
+  }
 };
 
 /* Controls state of render, everything that's read-only during render stage */
@@ -99,6 +113,8 @@ struct Render : public BaseRender {
                           const char *view_name) override;
   void compositor_free() override;
 
+  bool prepare_viewlayer(struct ViewLayer *view_layer, struct Depsgraph *depsgraph) override;
+
   char name[RE_MAXNAME] = "";
   int slot = 0;
 
@@ -150,7 +166,7 @@ struct Render : public BaseRender {
   blender::render::RealtimeCompositor *gpu_compositor = nullptr;
   std::mutex gpu_compositor_mutex;
 
-  /* callbacks */
+  /* Callbacks for the corresponding base class method implementation. */
   void (*display_init_cb)(void *handle, RenderResult *rr) = nullptr;
   void *dih = nullptr;
   void (*display_clear_cb)(void *handle, RenderResult *rr) = nullptr;
@@ -170,10 +186,6 @@ struct Render : public BaseRender {
   bool (*test_break_cb)(void *handle) = nullptr;
   void *tbh = nullptr;
 
-  /**
-   * Executed right before the initialization of the depsgraph, in order to modify some stuff in
-   * the viewlayer. The modified ids must be tagged in the depsgraph.
-   */
   bool (*prepare_viewlayer_cb)(void *handle, struct ViewLayer *vl, struct Depsgraph *depsgraph);
   void *prepare_vl_handle;