Nodes: refactor socket declarations

This commits adds a few common flags to `SocketDeclaration`
so that they are available for all socket types (hide label, hide
value, is multi input). This allows porting over the remaining
geometry nodes to the new declaration system.

Furthermore, this commit separates the concepts of the socket
declaration and corresponding builders. The builders are used
by nodes to declare which sockets they have (e.g. `FloatBuilder`).
The ready build socket declarations can then be consumed by
other systems such as the versioning code. Both use cases
need different APIs and those will change for independent reasons,
so it makes sense to separate the classes.

1 files changed, 82 insertions, 16 deletions

diff --git a/source/blender/nodes/NOD_node_declaration.hh b/source/blender/nodes/NOD_node_declaration.hh
index 7ba4ac52b86..8ca2b411a38 100644
--- a/source/blender/nodes/NOD_node_declaration.hh
+++ b/source/blender/nodes/NOD_node_declaration.hh
@@ -27,12 +27,19 @@ namespace blender::nodes {
 
 class NodeDeclarationBuilder;
 
+/**
+ * Describes a single input or output socket. This is subclassed for different socket types.
+ */
 class SocketDeclaration {
  protected:
   std::string name_;
   std::string identifier_;
+  bool hide_label_ = false;
+  bool hide_value_ = false;
+  bool is_multi_input_ = false;
 
   friend NodeDeclarationBuilder;
+  template<typename SocketDecl> friend class SocketDeclarationBuilder;
 
  public:
   virtual ~SocketDeclaration() = default;
@@ -43,6 +50,49 @@ class SocketDeclaration {
 
   StringRefNull name() const;
   StringRefNull identifier() const;
+
+ protected:
+  void set_common_flags(bNodeSocket &socket) const;
+  bool matches_common_data(const bNodeSocket &socket) const;
+};
+
+class BaseSocketDeclarationBuilder {
+ public:
+  virtual ~BaseSocketDeclarationBuilder() = default;
+};
+
+/**
+ * Wraps a #SocketDeclaration and provides methods to set it up correctly.
+ * This is separate from #SocketDeclaration, because it allows separating the API used by nodes to
+ * declare themselves from how the declaration is stored internally.
+ */
+template<typename SocketDecl>
+class SocketDeclarationBuilder : public BaseSocketDeclarationBuilder {
+ protected:
+  using Self = typename SocketDecl::Builder;
+  static_assert(std::is_base_of_v<SocketDeclaration, SocketDecl>);
+  SocketDecl *decl_;
+
+  friend class NodeDeclarationBuilder;
+
+ public:
+  Self &hide_label(bool value)
+  {
+    decl_->hide_label_ = value;
+    return *(Self *)this;
+  }
+
+  Self &hide_value(bool value)
+  {
+    decl_->hide_value_ = value;
+    return *(Self *)this;
+  }
+
+  Self &multi_input(bool value)
+  {
+    decl_->is_multi_input_ = value;
+    return *(Self *)this;
+  }
 };
 
 using SocketDeclarationPtr = std::unique_ptr<SocketDeclaration>;
@@ -67,12 +117,21 @@ class NodeDeclaration {
 class NodeDeclarationBuilder {
  private:
   NodeDeclaration &declaration_;
+  Vector<std::unique_ptr<BaseSocketDeclarationBuilder>> builders_;
 
  public:
   NodeDeclarationBuilder(NodeDeclaration &declaration);
 
-  template<typename DeclType> DeclType &add_input(StringRef name, StringRef identifier = "");
-  template<typename DeclType> DeclType &add_output(StringRef name, StringRef identifier = "");
+  template<typename DeclType>
+  typename DeclType::Builder &add_input(StringRef name, StringRef identifier = "");
+  template<typename DeclType>
+  typename DeclType::Builder &add_output(StringRef name, StringRef identifier = "");
+
+ private:
+  template<typename DeclType>
+  typename DeclType::Builder &add_socket(StringRef name,
+                                         StringRef identifier,
+                                         Vector<SocketDeclarationPtr> &r_decls);
 };
 
 /* --------------------------------------------------------------------
@@ -99,27 +158,34 @@ inline NodeDeclarationBuilder::NodeDeclarationBuilder(NodeDeclaration &declarati
 }
 
 template<typename DeclType>
-inline DeclType &NodeDeclarationBuilder::add_input(StringRef name, StringRef identifier)
+inline typename DeclType::Builder &NodeDeclarationBuilder::add_input(StringRef name,
+                                                                     StringRef identifier)
 {
-  static_assert(std::is_base_of_v<SocketDeclaration, DeclType>);
-  std::unique_ptr<DeclType> socket_decl = std::make_unique<DeclType>();
-  DeclType &ref = *socket_decl;
-  ref.name_ = name;
-  ref.identifier_ = identifier.is_empty() ? name : identifier;
-  declaration_.inputs_.append(std::move(socket_decl));
-  return ref;
+  return this->add_socket<DeclType>(name, identifier, declaration_.inputs_);
+}
+
+template<typename DeclType>
+inline typename DeclType::Builder &NodeDeclarationBuilder::add_output(StringRef name,
+                                                                      StringRef identifier)
+{
+  return this->add_socket<DeclType>(name, identifier, declaration_.outputs_);
 }
 
 template<typename DeclType>
-inline DeclType &NodeDeclarationBuilder::add_output(StringRef name, StringRef identifier)
+inline typename DeclType::Builder &NodeDeclarationBuilder::add_socket(
+    StringRef name, StringRef identifier, Vector<SocketDeclarationPtr> &r_decls)
 {
   static_assert(std::is_base_of_v<SocketDeclaration, DeclType>);
+  using Builder = typename DeclType::Builder;
   std::unique_ptr<DeclType> socket_decl = std::make_unique<DeclType>();
-  DeclType &ref = *socket_decl;
-  ref.name_ = name;
-  ref.identifier_ = identifier.is_empty() ? name : identifier;
-  declaration_.outputs_.append(std::move(socket_decl));
-  return ref;
+  std::unique_ptr<Builder> socket_decl_builder = std::make_unique<Builder>();
+  socket_decl_builder->decl_ = &*socket_decl;
+  socket_decl->name_ = name;
+  socket_decl->identifier_ = identifier.is_empty() ? name : identifier;
+  r_decls.append(std::move(socket_decl));
+  Builder &socket_decl_builder_ref = *socket_decl_builder;
+  builders_.append(std::move(socket_decl_builder));
+  return socket_decl_builder_ref;
 }
 
 /* --------------------------------------------------------------------