Canvas

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Object Hierarchy:

Description:

Content:

Properties:

• public CanvasAnchorType anchor { get; set; }
• public bool automatic_bounds { get; set; }
• public string background_color { set; }
• public RGBA background_color_gdk_rgba { set; }
  The color to use for the canvas background, specified as a GdkRGBA.
• public uint background_color_rgb { set; }
• public bool bounds_from_origin { get; set; }
• public double bounds_padding { get; set; }
• public bool clear_background { get; set; }
• public bool integer_layout { get; set; }
• public bool redraw_when_scrolled { get; set; }
• public double resolution_x { get; set; }
• public double resolution_y { get; set; }
• public double scale { get; set; }
• public double scale_x { get; set; }
• public double scale_y { get; set; }
• public Unit units { get; set; }
• public double x1 { get; set; }
• public double x2 { get; set; }
• public double y1 { get; set; }
• public double y2 { get; set; }

Static methods:

• public static void create_path (Array<CanvasPathCommand?> commands, Context cr)
  Creates the path specified by the given CanvasPathCommand array.
• public static Array<CanvasPathCommand?> parse_path_data (string path_data)
  Parses the given SVG path specification string.

Creation methods:

• public Canvas ()
  Creates a new Canvas widget.

Methods:

• public void convert_bounds_to_item_space (CanvasItem item, ref CanvasBounds bounds)
  Converts the given bounds in the canvas coordinate space to a bounding box in item space.
• public void convert_from_item_space (CanvasItem item, ref double x, ref double y)
  Converts a coordinate from the given item's coordinate space to the canvas coordinate space, applying all transformation matrices including the item's own transformation matrix, if it has one.
• public void convert_from_pixels (ref double x, ref double y)
  Converts a coordinate from pixels to the canvas coordinate space.
• public void convert_to_item_space (CanvasItem item, ref double x, ref double y)
  Converts a coordinate from the canvas coordinate space to the given item's coordinate space, applying all transformation matrices including the item's own transformation matrix, if it has one.
• public void convert_to_pixels (ref double x, ref double y)
  Converts a coordinate from the canvas coordinate space to pixels.
• public void convert_units_from_pixels (ref double x, ref double y)
  Converts a coordinate from pixels to the canvas's units, ignoring scaling and ignoring the coordinate space specified in the call to set_bounds.
• public void convert_units_to_pixels (ref double x, ref double y)
  Converts a coordinate from the canvas's units to pixels, ignoring scaling and ignoring the coordinate space specified in the call to set_bounds.
• public Context create_cairo_context ()
  Creates a cairo context, initialized with the default canvas settings.
• public virtual CanvasItem create_item (CanvasItemModel model)
  This function is only intended to be used when implementing new canvas items, typically container items such as CanvasGroup.
• public void get_bounds (out double left, out double top, out double right, out double bottom)
  Gets the bounds of the canvas, in canvas units.
• public double get_default_line_width ()
  Gets the default line width, which depends on the current units setting.
• public unowned CanvasItem get_item (CanvasItemModel model)
  Gets the canvas item associated with the given CanvasItemModel.
• public unowned CanvasItem get_item_at (double x, double y, bool is_pointer_event)
  Gets the item at the given point.
• public List<unowned CanvasItem> get_items_at (double x, double y, bool is_pointer_event)
  Gets all items at the given point.
• public List<unowned CanvasItem> get_items_in_area (CanvasBounds area, bool inside_area, bool allow_overlaps, bool include_containers)
  Gets a list of items inside or outside a given area.
• public unowned CanvasItem get_root_item ()
  Gets the root item of the canvas, usually a CanvasGroup.
• public unowned CanvasItemModel get_root_item_model ()
  Gets the root item model of the canvas.
• public double get_scale ()
  Gets the current scale of the canvas.
• public unowned CanvasItem get_static_root_item ()
  Gets the static root item of the canvas.
• public unowned CanvasItemModel get_static_root_item_model ()
  Gets the static root item model of the canvas.
• public void grab_focus (CanvasItem item)
  Grabs the keyboard focus for the given item.
• public GrabStatus keyboard_grab (CanvasItem item, bool owner_events, uint32 time)
  Attempts to grab the keyboard for the given item.
• public void keyboard_ungrab (CanvasItem item, uint32 time)
  Ungrabs the keyboard, if the given item has the keyboard grab.
• public GrabStatus pointer_grab (CanvasItem item, EventMask event_mask, Cursor? cursor, uint32 time)
  Attempts to grab the pointer for the given item.
• public void pointer_ungrab (CanvasItem item, uint32 time)
  Ungrabs the pointer, if the given item has the pointer grab.
• public void register_widget_item (CanvasWidget witem)
  This function should only be used by CanvasWidget and subclass implementations.
• public void render (Context cr, CanvasBounds? bounds, double scale)
  Renders all or part of a canvas to the given cairo context.
• public void request_item_redraw (CanvasBounds bounds, bool is_static)
  This function is only intended to be used by subclasses of Canvas or CanvasItem implementations.
• public void request_redraw (CanvasBounds bounds)
  This function is only intended to be used by subclasses of Canvas or CanvasItem implementations.
• public void request_update ()
  This function is only intended to be used by subclasses of Canvas or CanvasItem implementations.
• public void scroll_to (double left, double top)
  Scrolls the canvas, placing the given point as close to the top-left of the view as possible.
• public void set_bounds (double left, double top, double right, double bottom)
  Sets the bounds of the Canvas, in canvas units.
• public void set_root_item (CanvasItem item)
  Sets the root item of the canvas.
• public void set_root_item_model (CanvasItemModel model)
  Sets the root item model of the canvas.
• public void set_scale (double scale)
  Sets the scale of the canvas.
• public void set_static_root_item (CanvasItem item)
  Sets the static root item.
• public void set_static_root_item_model (CanvasItemModel model)
  Sets the static root item model.
• public void unregister_item (CanvasItemModel model)
  This function is only intended to be used when implementing new canvas items.
• public void unregister_widget_item (CanvasWidget witem)
  This function should only be used by CanvasWidget and subclass implementations.
• public void update ()
  This function is only intended to be used by subclasses of Canvas or CanvasItem implementations.

Signals:

• public virtual signal void item_created (CanvasItem item, CanvasItemModel model)
  This is emitted when a new canvas item is created, in model/view mode.

Inherited Members: