text: /*************************************************************************/
  /*  scroll_bar.h                                                         */
  /*************************************************************************/
  /*                       This file is part of:                           */
  /*                           GODOT ENGINE                                */
  /*                      https://godotengine.org                          */
  /*************************************************************************/
  /* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur.                 */
  /* Copyright (c) 2014-2018 Godot Engine contributors (cf. AUTHORS.md)    */
  /*                                                                       */
  /* Permission is hereby granted, free of charge, to any person obtaining */
  /* a copy of this software and associated documentation files (the       */
  /* "Software"), to deal in the Software without restriction, including   */
  /* without limitation the rights to use, copy, modify, merge, publish,   */
  /* distribute, sublicense, and/or sell copies of the Software, and to    */
  /* permit persons to whom the Software is furnished to do so, subject to */
  /* the following conditions:                                             */
  /*                                                                       */
  /* The above copyright notice and this permission notice shall be        */
  /* included in all copies or substantial portions of the Software.       */
  /*                                                                       */
  /* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
  /* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
  /* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
  /* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
  /* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
  /* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
  /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
  /*************************************************************************/
  
  #ifndef SCROLL_BAR_H
  #define SCROLL_BAR_H
  
  #include "scene/gui/range.h"
  
  /**
  	@author Juan Linietsky <reduzio@gmail.com>
  */
  
  class ScrollBar : public Range {
  
  	GDCLASS(ScrollBar, Range);
  
  	enum HighlightStatus {
  		HIGHLIGHT_NONE,
  		HIGHLIGHT_DECR,
  		HIGHLIGHT_RANGE,
  		HIGHLIGHT_INCR,
  	};
  
  	static bool focus_by_default;
  
  	Orientation orientation;
  	Size2 size;
  	float custom_step;
  
  	HighlightStatus highlight;
  
  	struct Drag {
  
  		bool active;
  		float pos_at_click;
  		float value_at_click;
  	} drag;
  
  	double get_grabber_size() const;
  	double get_grabber_min_size() const;
  	double get_area_size() const;
  	double get_area_offset() const;
  	double get_click_pos(const Point2 &p_pos) const;
  	double get_grabber_offset() const;
  
  	static void set_can_focus_by_default(bool p_can_focus);
  
  	Node *drag_node;
  	NodePath drag_node_path;
  
  	Vector2 drag_node_speed;
  	Vector2 drag_node_accum;
  	Vector2 drag_node_from;
  	Vector2 last_drag_node_accum;
  	float last_drag_node_time;
  	float time_since_motion;
  	bool drag_node_touching;
  	bool drag_node_touching_deaccel;
  	bool click_handled;
  
  	bool scrolling;
  	double target_scroll;
  	bool smooth_scroll_enabled;
  
  	void _drag_node_exit();
  	void _drag_node_input(const Ref<InputEvent> &p_input);
  
  	void _gui_input(Ref<InputEvent> p_event);
  
  protected:
  	void _notification(int p_what);
  
  	static void _bind_methods();
  
  public:
  	void set_custom_step(float p_custom_step);
  	float get_custom_step() const;
  
  	void set_drag_node(const NodePath &p_path);
  	NodePath get_drag_node() const;
  
  	void set_smooth_scroll_enabled(bool p_enable);
  	bool is_smooth_scroll_enabled() const;
  
  	virtual Size2 get_minimum_size() const;
  	ScrollBar(Orientation p_orientation = VERTICAL);
  	~ScrollBar();
  };
  
  class HScrollBar : public ScrollBar {
  
  	GDCLASS(HScrollBar, ScrollBar);
  
  public:
  	HScrollBar() :
  			ScrollBar(HORIZONTAL) { set_v_size_flags(0); }
  };
  
  class VScrollBar : public ScrollBar {
  
  	GDCLASS(VScrollBar, ScrollBar);
  
  public:
  	VScrollBar() :
  			ScrollBar(VERTICAL) { set_h_size_flags(0); }
  };
  
  #endif
  