The Gui Module

Gui is the Qt desktop application built on top of Engine. Every class here may use Engine; several implement the …I interfaces the Engine calls back into (see Design Techniques and Idioms). Like some Engine classes, several large Gui classes are split across numbered .cpp files (Gui20.cpp, ViewerTab30.cpp …) that all implement one class.

Main window and application

  • Gui (Gui.cpp and Gui05–Gui50.cpp, GuiPrivate.*): the main window. Owns the docked panes, menus, the node graph, viewers and editors.

  • GuiApplicationManager (GuiApplicationManager*.cpp): the AppManager subclass for GUI mode — shortcuts (ActionShortcuts), icons/resources, the application event loop, known plug-in menus.

  • GuiAppInstance: the AppInstance subclass that owns a Gui.

  • Docking/layout: TabWidget, Splitter, FloatingWidget, SerializableWindow, ProjectGuiSerialization (layouts are saved with the project).

The node graph

  • NodeGraph (NodeGraph.cpp and NodeGraph05–NodeGraph45.cpp, NodeGraphPrivate.*): the QGraphicsView canvas; implements NodeGraphI.

  • NodeGui (NodeGui.cpp): the on-canvas node item; implements NodeGuiI. BackdropGui, DotGui, Edge (connections), NodeGraphTextItem/NodeGraphRectItem are the graphics items.

  • NodeGraphUndoRedo and NodeCreationDialog handle edits and node creation. Node clipboard: NodeClipBoard.

The viewer

  • ViewerGL (ViewerGL.cpp, ViewerGLPrivate.*): the QOpenGLWidget viewport; implements OpenGLViewerI. Draws the rendered textures, overlays and the user’s interactions.

  • ViewerTab (ViewerTab.cpp and ViewerTab10–40.cpp, ViewerTabPrivate.*): the panel around the GL widget — playback controls, channel/view selectors, the timeline.

  • InfoViewerWidget, Histogram (also a QOpenGLWidget), TimeLineGui.

Animation editors

  • CurveEditor / CurveWidget (CurveWidget.cpp, CurveWidgetPrivate.*, CurveGui): the keyframe curve editor (QOpenGLWidget).

  • DopeSheet / DopeSheetView / DopeSheetEditor / DopeSheetHierarchyView (with DopeSheetEditorUndoRedo): the dope sheet.

  • Undo/redo for curves: CurveEditorUndoRedo.

Parameter panels (Knob GUIs)

  • DockablePanel (DockablePanel.cpp, DockablePanelPrivate.*): a node’s settings panel; implements DockablePanelI.

  • KnobGui (KnobGui.cpp, KnobGui10/20.cpp, KnobGuiPrivate.*): base class implementing KnobGuiI; KnobGuiFactory builds the right widget for each knob type. Concrete widgets: KnobGuiValue (int/double), KnobGuiBool, KnobGuiChoice, KnobGuiColor, KnobGuiString, KnobGuiFile, KnobGuiButton, KnobGuiGroup, KnobGuiParametric, KnobGuiSeparator, KnobGuiTable.

  • KnobUndoCommand (undo for parameter edits), KnobWidgetDnD (drag-and- drop linking), ManageUserParamsDialog/AddKnobDialog (user parameters), EditExpressionDialog/EditScriptDialog (Python expressions/scripts).

Tool panels

  • RotoPanel (RotoPanel.cpp): the roto/paint item tree and tools.

  • TrackerPanel (TrackerPanel.cpp) and MultiInstancePanel: the tracker’s marker table.

  • PreferencesPanel: the settings UI, generated from the Settings knobs.

  • HostOverlay (HostOverlay.cpp): draws the host-provided overlays (position/transform/corner-pin handles) for plug-ins that request them.

Custom widgets and helpers

Natron ships many hand-built widgets to get the look and behavior it wants: ComboBox, SpinBox (+ SpinBoxValidator), Button, Label, LineEdit, ScaleSliderQWidget, ColorSelectorWidget / QtColorTriangle, Menu, ClickableLabel, AnimatedCheckBox, TableModelView (a generic model/view table), ScriptTextEdit / ScriptEditor (the Python console), ProgressPanel / ProgressTaskInfo, MessageBox / LogWindow / AboutWindow / SplashScreen, and the file dialog SequenceFileDialog (sequence-aware, backed by Engine’s FileSystemModel). QtEnumConvert translates between Qt enums and Natron’s toolkit-independent enums (Global/Enums.h, KeySymbols.h) so Engine code never sees Qt key/modifier types.

GUI Python integration

PyGuiApp and PythonPanels expose the GUI to Python (custom panels and menus), bound through Shiboken with typesystem_natronGui.xml. See Python Bindings (Shiboken / PySide).