1 files changed, 224 insertions, 0 deletions
diff --git a/src/ui/widget/canvas.h b/src/ui/widget/canvas.h
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+++ b/src/ui/widget/canvas.h
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+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#ifndef INKSCAPE_UI_WIDGET_CANVAS_H
+#define INKSCAPE_UI_WIDGET_CANVAS_H
+/*
+ * Authors:
+ *   Tavmjong Bah
+ *   PBS <pbs3141@gmail.com>
+ *
+ * Copyright (C) 2022 Authors
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <memory>
+#include <gtkmm.h>
+#include <2geom/rect.h>
+#include <2geom/int-rect.h>
+#include "display/rendermode.h"
+#include "optglarea.h"
+
+class SPDesktop;
+
+namespace Inkscape {
+
+class CanvasItem;
+class CanvasItemGroup;
+class Drawing;
+
+namespace UI {
+namespace Widget {
+
+class CanvasPrivate;
+
+/**
+ * A widget for Inkscape's canvas.
+ */
+class Canvas : public OptGLArea
+{
+    using parent_type = OptGLArea;
+
+public:
+    Canvas();
+    ~Canvas() override;
+
+    /* Configuration */
+
+    // Desktop (Todo: Remove.)
+    void set_desktop(SPDesktop *desktop) { _desktop = desktop; }
+    SPDesktop *get_desktop() const { return _desktop; }
+
+    // Drawing
+    void set_drawing(Inkscape::Drawing *drawing);
+
+    // Canvas item root
+    CanvasItemGroup *get_canvas_item_root() const;
+
+    // Geometry
+    void set_pos   (const Geom::IntPoint &pos);
+    void set_pos   (const Geom::Point    &fpos) { set_pos(fpos.round()); }
+    void set_affine(const Geom::Affine   &affine);
+    const Geom::IntPoint &get_pos   () const { return _pos; }
+    const Geom::Affine   &get_affine() const { return _affine; }
+    const Geom::Affine   &get_geom_affine() const; // tool-base.cpp (todo: remove this dependency)
+
+    // Background
+    void set_desk  (uint32_t rgba);
+    void set_border(uint32_t rgba);
+    void set_page  (uint32_t rgba);
+    uint32_t get_effective_background() const; // This function is now wrong.
+
+    //  Rendering modes
+    void set_render_mode(Inkscape::RenderMode mode);
+    void set_color_mode (Inkscape::ColorMode  mode);
+    void set_split_mode (Inkscape::SplitMode  mode);
+    Inkscape::RenderMode get_render_mode() const { return _render_mode; }
+    Inkscape::ColorMode  get_color_mode()  const { return _color_mode; }
+    Inkscape::SplitMode  get_split_mode()  const { return _split_mode; }
+    void set_clip_to_page_mode(bool clip);
+
+    // CMS
+    void set_cms_key(std::string key);
+    const std::string &get_cms_key() const { return _cms_key; }
+    void set_cms_active(bool active) { _cms_active = active; }
+    bool get_cms_active() const { return _cms_active; }
+
+    /* Observers */
+
+    // Geometry
+    Geom::IntPoint get_dimensions() const;
+    bool world_point_inside_canvas(Geom::Point const &world) const; // desktop-events.cpp
+    Geom::Point canvas_to_world(Geom::Point const &window) const;
+    Geom::IntRect get_area_world() const;
+    bool canvas_point_in_outline_zone(Geom::Point const &world) const;
+
+    // State
+    bool is_dragging() const { return _is_dragging; } // selection-chemistry.cpp
+
+    // Mouse
+    std::optional<Geom::Point> get_last_mouse() const; // desktop-widget.cpp
+
+    /* Methods */
+
+    // Invalidation
+    void redraw_all();                  // Mark everything as having changed.
+    void redraw_area(Geom::Rect const &area); // Mark a rectangle of world space as having changed.
+    void redraw_area(int x0, int y0, int x1, int y1);
+    void redraw_area(Geom::Coord x0, Geom::Coord y0, Geom::Coord x1, Geom::Coord y1);
+    void request_update();              // Mark geometry as needing recalculation.
+
+    // Callback run on destructor of any canvas item
+    void canvas_item_destructed(Inkscape::CanvasItem *item);
+
+    // State
+    Inkscape::CanvasItem *get_current_canvas_item() const { return _current_canvas_item; }
+    void                  set_current_canvas_item(Inkscape::CanvasItem *item) {
+        _current_canvas_item = item;
+    }
+    Inkscape::CanvasItem *get_grabbed_canvas_item() const { return _grabbed_canvas_item; }
+    void                  set_grabbed_canvas_item(Inkscape::CanvasItem *item, Gdk::EventMask mask) {
+        _grabbed_canvas_item = item;
+        _grabbed_event_mask = mask;
+    }
+    void set_all_enter_events(bool on) { _all_enter_events = on; }
+
+    void enable_autoscroll();
+
+protected:
+    void get_preferred_width_vfunc (int &minimum_width,  int &natural_width ) const override;
+    void get_preferred_height_vfunc(int &minimum_height, int &natural_height) const override;
+
+    // Event handlers
+    bool on_scroll_event        (GdkEventScroll*  ) override;
+    bool on_button_event        (GdkEventButton*  );
+    bool on_button_press_event  (GdkEventButton*  ) override;
+    bool on_button_release_event(GdkEventButton*  ) override;
+    bool on_enter_notify_event  (GdkEventCrossing*) override;
+    bool on_leave_notify_event  (GdkEventCrossing*) override;
+    bool on_focus_in_event      (GdkEventFocus*   ) override;
+    bool on_key_press_event     (GdkEventKey*     ) override;
+    bool on_key_release_event   (GdkEventKey*     ) override;
+    bool on_motion_notify_event (GdkEventMotion*  ) override;
+
+    void on_realize() override;
+    void on_unrealize() override;
+    void on_size_allocate(Gtk::Allocation&) override;
+
+    Glib::RefPtr<Gdk::GLContext> create_context() override;
+    void paint_widget(const Cairo::RefPtr<Cairo::Context>&) override;
+
+private:
+    /* Configuration */
+
+    // Desktop
+    SPDesktop *_desktop = nullptr;
+
+    // Drawing
+    Inkscape::Drawing *_drawing = nullptr;
+
+    // Geometry
+    Geom::IntPoint _pos = {0, 0}; ///< Coordinates of top-left pixel of canvas view within canvas.
+    Geom::Affine _affine; ///< The affine that we have been requested to draw at.
+
+    // Rendering modes
+    Inkscape::RenderMode _render_mode = Inkscape::RenderMode::NORMAL;
+    Inkscape::SplitMode  _split_mode  = Inkscape::SplitMode::NORMAL;
+    Inkscape::ColorMode  _color_mode  = Inkscape::ColorMode::NORMAL;
+
+    // CMS
+    std::string _cms_key;
+    bool _cms_active = false;
+
+    /* Internal state */
+
+    // Event handling/item picking
+    GdkEvent _pick_event;        ///< Event used to find currently selected item.
+    bool     _in_repick;         ///< For tracking recursion of pick_current_item().
+    bool     _left_grabbed_item; ///< ?
+    bool     _all_enter_events;  ///< Keep all enter events. Only set true in connector-tool.cpp.
+    bool     _is_dragging;       ///< Used in selection-chemistry to block undo/redo.
+    int      _state;             ///< Last known modifier state (SHIFT, CTRL, etc.).
+
+    Inkscape::CanvasItem *_current_canvas_item;     ///< Item containing cursor, nullptr if none.
+    Inkscape::CanvasItem *_current_canvas_item_new; ///< Item to become _current_item, nullptr if none.
+    Inkscape::CanvasItem *_grabbed_canvas_item;     ///< Item that holds a pointer grab; nullptr if none.
+    Gdk::EventMask _grabbed_event_mask;
+
+    // Drawing
+    bool _need_update = true; // Set true so setting CanvasItem bounds are calculated at least once.
+
+    // Split view
+    Inkscape::SplitDirection _split_direction;
+    Geom::Point _split_frac;
+    Inkscape::SplitDirection _hover_direction;
+    bool _split_dragging;
+    Geom::IntPoint _split_drag_start;
+
+    void set_cursor();
+
+    // Opaque pointer to implementation
+    friend class CanvasPrivate;
+    std::unique_ptr<CanvasPrivate> d;
+};
+
+} // namespace Widget
+} // namespace UI
+} // namespace Inkscape
+
+#endif // INKSCAPE_UI_WIDGET_CANVAS_H
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :