1 files changed, 56 insertions, 0 deletions
diff --git a/source/blender/compositor/realtime_compositor/COM_node_operation.hh b/source/blender/compositor/realtime_compositor/COM_node_operation.hh
new file mode 100644
index 00000000000..94bc4dfd39d
--- /dev/null
+++ b/source/blender/compositor/realtime_compositor/COM_node_operation.hh
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#pragma once
+
+#include "BLI_string_ref.hh"
+
+#include "DNA_node_types.h"
+
+#include "NOD_derived_node_tree.hh"
+
+#include "COM_context.hh"
+#include "COM_operation.hh"
+#include "COM_scheduler.hh"
+
+namespace blender::realtime_compositor {
+
+using namespace nodes::derived_node_tree_types;
+
+/* ------------------------------------------------------------------------------------------------
+ * Node Operation
+ *
+ * A node operation is a subclass of operation that nodes should implement and instantiate in the
+ * get_compositor_operation function of bNodeType, passing the inputs given to that function to the
+ * constructor. This class essentially just implements a default constructor that populates output
+ * results for all outputs of the node as well as input descriptors for all inputs of the nodes
+ * based on their socket declaration. The class also provides some utility methods for easier
+ * implementation of nodes. */
+class NodeOperation : public Operation {
+ private:
+  /* The node that this operation represents. */
+  DNode node_;
+
+ public:
+  /* Populate the output results based on the node outputs and populate the input descriptors based
+   * on the node inputs. */
+  NodeOperation(Context &context, DNode node);
+
+  /* Compute and set the initial reference counts of all the results of the operation. The
+   * reference counts of the results are the number of operations that use those results, which is
+   * computed as the number of inputs whose node is part of the schedule and is linked to the
+   * output corresponding to each result. The node execution schedule is given as an input. */
+  void compute_results_reference_counts(const Schedule &schedule);
+
+ protected:
+  /* Returns a reference to the derived node that this operation represents. */
+  const DNode &node() const;
+
+  /* Returns a reference to the node that this operation represents. */
+  const bNode &bnode() const;
+
+  /* Returns true if the output identified by the given identifier is needed and should be
+   * computed, otherwise returns false. */
+  bool should_compute_output(StringRef identifier);
+};
+
+}  // namespace blender::realtime_compositor