Adds Node Group functionality

.github/workflows/cmake_build.yml

@@ -30,9 +30,9 @@ jobs:
           - toolchain: linux-gcc
             os: ubuntu-22.04
             compiler: gcc
-            qt_version: "5.15.2"
+            qt_version: "6.3.0"
             modules: ""
-            use_qt6: "OFF"
+            use_qt6: "ON"
 
           - toolchain: macos-clang
             os: macos-latest

CMakeLists.txt

@@ -87,6 +87,8 @@ set(CPP_SOURCE_FILES
   src/StyleCollection.cpp
   src/UndoCommands.cpp
   src/locateNode.cpp
+  src/GroupGraphicsObject.cpp
+  src/NodeGroup.cpp
   resources/resources.qrc
 )
 
@@ -127,6 +129,8 @@ set(HPP_HEADER_FILES
   include/QtNodes/internal/DefaultVerticalNodeGeometry.hpp
   include/QtNodes/internal/NodeConnectionInteraction.hpp
   include/QtNodes/internal/UndoCommands.hpp
+  include/QtNodes/internal/NodeGroup.hpp
+  include/QtNodes/internal/GroupGraphicsObject.hpp
 )
 
 # If we want to give the option to build a static library,

examples/calculator/main.cpp

@@ -112,6 +112,11 @@ int main(int argc, char *argv[])
         mainWidget.setWindowModified(true);
     });
 
+    if (scene->groupingEnabled()) {
+        auto loadGroupAction = menu->addAction("Load Group...");
+        QObject::connect(loadGroupAction, &QAction::triggered, [scene] { scene->loadGroupFile(); });
+    }
+
     mainWidget.setWindowTitle("[*]Data Flow: simplest calculator");
     mainWidget.resize(800, 600);
     // Center window.

include/QtNodes/GroupGraphicsObject

@@ -0,0 +1 @@
+#include "internal/GroupGraphicsObject.hpp"

include/QtNodes/NodeGroup

@@ -0,0 +1 @@
+#include "internal/NodeGroup.hpp"

include/QtNodes/internal/BasicGraphicsScene.hpp

@@ -5,10 +5,11 @@
 #include "ConnectionIdHash.hpp"
 #include "Definitions.hpp"
 #include "Export.hpp"
+#include "GroupGraphicsObject.hpp"
+#include "NodeGroup.hpp"
+#include "UndoCommands.hpp"
 
-#include "QUuidStdHash.hpp"
-
-#include <QtCore/QUuid>
+#include <QtCore/QJsonObject>
 #include <QtWidgets/QGraphicsScene>
 #include <QtWidgets/QMenu>
 
@@ -27,6 +28,11 @@ class AbstractNodePainter;
 class ConnectionGraphicsObject;
 class NodeGraphicsObject;
 class NodeStyle;
+class DeleteCommand;
+class CopyCommand;
+class NodeGroup;
+class GroupGraphicsObject;
+struct ConnectionId;
 
 /// An instance of QGraphicsScene, holds connections and nodes.
 class NODE_EDITOR_PUBLIC BasicGraphicsScene : public QGraphicsScene
@@ -62,6 +68,17 @@ class NODE_EDITOR_PUBLIC BasicGraphicsScene : public QGraphicsScene
 
     QUndoStack &undoStack();
 
+    /**
+     * @brief Setter for the _groupingEnabled flag.
+     * @param boolean to set or not the flag.
+     */
+    void setGroupingEnabled(bool enabled);
+
+    /**
+     * @brief Getter for the _groupingEnabled flag.
+     */
+    bool groupingEnabled() const { return _groupingEnabled; }
+
 public:
     /**
      * @brief Creates a "draft" instance of ConnectionGraphicsObject.
@@ -87,6 +104,83 @@ class NODE_EDITOR_PUBLIC BasicGraphicsScene : public QGraphicsScene
     /// Deletes all the nodes. Connections are removed automatically.
     void clearScene();
 
+    /**
+     * @brief Creates a list of the connections that are incident only to nodes within a
+     * given group.
+     * @param groupID ID of the desired group.
+     * @return List of (pointers of) connections whose both endpoints belong to members of
+     * the specified group.
+     */
+    std::vector<std::shared_ptr<ConnectionId>> connectionsWithinGroup(GroupId groupID);
+    /**
+     * @brief Creates a group in the scene containing the given nodes.
+     * @param nodes Reference to the list of nodes to be included in the group.
+     * @param name Group's name.
+     * @param groupId Group's id.
+     * @return Pointer to the newly-created group.
+     */
+    std::weak_ptr<NodeGroup> createGroup(std::vector<NodeGraphicsObject *> &nodes,
+                                         QString name = QStringLiteral(""),
+                                         GroupId groupId = InvalidGroupId);
+
+    /**
+     * @brief Creates a group in the scene containing the currently selected nodes.
+     * @param name Group's name
+     * @return Pointer to the newly-created group.
+     */
+    std::weak_ptr<NodeGroup> createGroupFromSelection(QString groupName = QStringLiteral(""));
+
+    /**
+     * @brief Restores a group from a JSON object.
+     * @param groupJson JSON object containing the group data.
+     * @return Pair consisting of a pointer to the newly-created group and the mapping
+     * between old and new nodes.
+     */
+    std::pair<std::weak_ptr<NodeGroup>, std::unordered_map<GroupId, GroupId>> restoreGroup(
+        QJsonObject const &groupJson);
+
+    /**
+     * @brief Returns a const reference to the mapping of existing groups.
+     */
+    std::unordered_map<GroupId, std::shared_ptr<NodeGroup>> const &groups() const;
+
+    /**
+     * @brief Loads a group from a file specified by the user.
+     * @return Pointer to the newly-created group.
+     */
+    std::weak_ptr<NodeGroup> loadGroupFile();
+
+    /**
+     * @brief Saves a group in a .group file.
+     * @param groupID Group's id.
+     */
+    void saveGroupFile(GroupId groupID);
+
+    /**
+     * @brief Calculates the selected nodes.
+     * @return Vector containing the NodeGraphicsObject pointers related to the selected nodes.
+     */
+    std::vector<NodeGraphicsObject *> selectedNodes() const;
+
+    /**
+     * @brief Calculates the selected groups.
+     * @return Vector containing the GroupGraphicsObject pointers related to the selected groups.
+     */
+    std::vector<GroupGraphicsObject *> selectedGroups() const;
+
+    /**
+     * @brief Adds a node to a group, if both node and group exists.
+     * @param nodeId Node's id.
+     * @param groupId Group's id.
+     */
+    void addNodeToGroup(NodeId nodeId, GroupId groupId);
+
+    /**
+     * @brief Removes a node from a group, if the node exists and is within a group.
+     * @param nodeId Node's id.
+     */
+    void removeNodeFromGroup(NodeId nodeId);
+
 public:
     /**
      * @returns NodeGraphicsObject associated with the given nodeId.
@@ -111,6 +205,17 @@ class NODE_EDITOR_PUBLIC BasicGraphicsScene : public QGraphicsScene
      */
     virtual QMenu *createSceneMenu(QPointF const scenePos);
 
+    /**
+     * @brief Creates the default menu when a node is selected.
+     */
+    QMenu *createStdMenu(QPointF const scenePos);
+
+    /**
+     * @brief Creates the menu when a group is selected.
+     * @param groupGo reference to the GroupGraphicsObject related to the selected group.
+     */
+    QMenu *createGroupMenu(QPointF const scenePos, GroupGraphicsObject *groupGo);
+
 Q_SIGNALS:
     void modified(BasicGraphicsScene *);
     void nodeMoved(NodeId const nodeId, QPointF const &newLocation);
@@ -141,6 +246,24 @@ class NODE_EDITOR_PUBLIC BasicGraphicsScene : public QGraphicsScene
     /// Redraws adjacent nodes for given `connectionId`
     void updateAttachedNodes(ConnectionId const connectionId, PortType const portType);
 
+    /**
+     * @brief Loads a JSON object that represents a node, with the option
+     * to keep the stored node id or generate a new one.
+     * @param nodeJson The JSON object representing a node.
+     * @param keepOriginalId If true, the loaded node will have the same id as the one stored in
+     * the file; otherwise, a new id will be generated
+     * @return A reference to the NodeGraphicsObject related to the loaded node.
+     */
+    NodeGraphicsObject &loadNodeToMap(QJsonObject nodeJson, bool keepOriginalId = false);
+
+    /**
+     * @brief Loads a connection between nodes from a JSON file.
+     * @param connectionJson JSON object that stores the connection's endpoints.
+     * @param nodeIdMap Map of nodes (i.e. all possible endpoints).
+     */
+    void loadConnectionToMap(QJsonObject const &connectionJson,
+                             std::unordered_map<NodeId, NodeId> const &nodeIdMap);
+
 public Q_SLOTS:
     /// Slot called when the `connectionId` is erased form the AbstractGraphModel.
     virtual void onConnectionDeleted(ConnectionId const connectionId);
@@ -155,21 +278,37 @@ public Q_SLOTS:
     virtual void onNodeClicked(NodeId const nodeId);
     virtual void onModelReset();
 
+    /**
+     * @brief Slot called to trigger the copy command action.
+     */
+    void onCopySelectedObjects() { undoStack().push(new CopyCommand(this)); }
+
+    /**
+     * @brief Slot called to trigger the delete command action.
+     */
+    void onDeleteSelectedObjects() { undoStack().push(new DeleteCommand(this)); }
+
 private:
     AbstractGraphModel &_graphModel;
 
     using UniqueNodeGraphicsObject = std::unique_ptr<NodeGraphicsObject>;
     using UniqueConnectionGraphicsObject = std::unique_ptr<ConnectionGraphicsObject>;
+    using SharedGroup = std::shared_ptr<NodeGroup>;
 
     std::unordered_map<NodeId, UniqueNodeGraphicsObject> _nodeGraphicsObjects;
     std::unordered_map<ConnectionId, UniqueConnectionGraphicsObject> _connectionGraphicsObjects;
+    GroupId nextGroupId();
+
+    std::unordered_map<GroupId, SharedGroup> _groups{};
+    GroupId _nextGroupId{0};
     std::unique_ptr<ConnectionGraphicsObject> _draftConnection;
     std::unique_ptr<AbstractNodeGeometry> _nodeGeometry;
     std::unique_ptr<AbstractNodePainter> _nodePainter;
     std::unique_ptr<AbstractConnectionPainter> _connectionPainter;
     bool _nodeDrag;
     QUndoStack *_undoStack;
     Qt::Orientation _orientation;
+    bool _groupingEnabled;
 };
 
 } // namespace QtNodes

include/QtNodes/internal/Definitions.hpp

@@ -18,23 +18,23 @@ NODE_EDITOR_PUBLIC Q_NAMESPACE
 Q_NAMESPACE_EXPORT(NODE_EDITOR_PUBLIC)
 #endif
 
-/**
+    /**
  * Constants used for fetching QVariant data from GraphModel.
  */
-enum class NodeRole {
-    Type = 0,             ///< Type of the current node, usually a string.
-    Position = 1,         ///< `QPointF` positon of the node on the scene.
-    Size = 2,             ///< `QSize` for resizable nodes.
-    CaptionVisible = 3,   ///< `bool` for caption visibility.
-    Caption = 4,          ///< `QString` for node caption.
-    Style = 5,            ///< Custom NodeStyle as QJsonDocument
-    InternalData = 6,     ///< Node-stecific user data as QJsonObject
-    InPortCount = 7,      ///< `unsigned int`
-    OutPortCount = 9,     ///< `unsigned int`
-    Widget = 10,          ///< Optional `QWidget*` or `nullptr`
-    ValidationState = 11, ///< Enum NodeValidationState of the node
-    ProcessingStatus = 12 ///< Enum NodeProcessingStatus of the node
-};
+    enum class NodeRole {
+        Type = 0,             ///< Type of the current node, usually a string.
+        Position = 1,         ///< `QPointF` positon of the node on the scene.
+        Size = 2,             ///< `QSize` for resizable nodes.
+        CaptionVisible = 3,   ///< `bool` for caption visibility.
+        Caption = 4,          ///< `QString` for node caption.
+        Style = 5,            ///< Custom NodeStyle as QJsonDocument
+        InternalData = 6,     ///< Node-stecific user data as QJsonObject
+        InPortCount = 7,      ///< `unsigned int`
+        OutPortCount = 9,     ///< `unsigned int`
+        Widget = 10,          ///< Optional `QWidget*` or `nullptr`
+        ValidationState = 11, ///< Enum NodeValidationState of the node
+        ProcessingStatus = 12 ///< Enum NodeProcessingStatus of the node
+    };
 Q_ENUM_NS(NodeRole)
 
 /**
@@ -94,6 +94,11 @@ using NodeId = unsigned int;
 
 static constexpr NodeId InvalidNodeId = std::numeric_limits<NodeId>::max();
 
+/// Unique Id associated with each node group.
+using GroupId = unsigned int;
+
+static constexpr GroupId InvalidGroupId = std::numeric_limits<GroupId>::max();
+
 /**
  * A unique connection identificator that stores
  * out `NodeId`, out `PortIndex`, in `NodeId`, in `PortIndex`

include/QtNodes/internal/GraphicsView.hpp

@@ -91,6 +91,7 @@ public Q_SLOTS:
 private:
     QAction *_clearSelectionAction = nullptr;
     QAction *_deleteSelectionAction = nullptr;
+    QAction *_cutSelectionAction = nullptr;
     QAction *_duplicateSelectionAction = nullptr;
     QAction *_copySelectionAction = nullptr;
     QAction *_pasteAction = nullptr;