/******************************************************************************/
enum SLIDEBAR_BACK_CLICK_MODE : Byte // action when clicking on the background of the SlideBar
{
   SBC_OFF    , // nothing happens
   SBC_STEP   , // one time scroll   will be performed by a single step
   SBC_SMOOTH , // smooth scrolling  will be performed as long as the click is hold
   SBC_SET_POS, // slidebar position will be immediately set to the click position
};
const_mem_addr STRUCT(SlideBar , GuiObj) // Gui SlideBar !! must be stored in constant memory address !!
//{
   Button                   button[3]; // 3 buttons (0=middle, 1=left/up, 2=right/down)
   SLIDEBAR_BACK_CLICK_MODE sbc      ; // default=SBC_STEP

   // manage
   SlideBar& del   (                );                              // delete
   SlideBar& create(                );                              // create
   SlideBar& create(C Rect     &rect) {return create().rect(rect);} // create and set rectangle
   SlideBar& create(C SlideBar &src );                              // create from 'src'

   // set / get
   SlideBar&  setLengths  (Flt length, Flt length_total         );                         // set, 'length'=covered length, 'length_total'=total length
   SlideBar&  set         (Flt step  , SET_MODE mode=SET_DEFAULT);                         // set slidebar step                 (0..1)
   Flt        operator()  (                                     )C;                        // get slidebar step                 (0..1)
   Flt        wantedOffset(                                     )C;                        // get slidebar offset desired       (0..length_total-length)
   Flt              offset(                                     )C {return _offset      ;} // get slidebar offset at the moment (0..length_total-length)
   SlideBar&        offset(Flt offset, SET_MODE mode=SET_DEFAULT);                         // set slidebar offset               (0..length_total-length)
   Flt         length     (                                     )C {return _length      ;} // get slidebar length
   Flt         lengthTotal(                                     )C {return _length_total;} // get slidebar length total
   SlideBar&      skin    (C GuiSkinPtr &skin                   );                         // set skin override, default=null (if set to null then current value of 'Gui.skin' is used), changing this value will automatically change the skin of the SlideBar buttons
 C GuiSkinPtr&    skin    (                                     )C {return _skin        ;} // get skin override, default=null (if set to null then current value of 'Gui.skin' is used)
   GuiSkin*    getSkin    (                                     )C {return _skin ? _skin() : Gui.skin();} // get actual skin

   Bool wantedAtEnd(Flt eps=EPS)C {return wantedOffset()+length()+eps>=lengthTotal();} // if slidebar is wanted to be at the end

            SlideBar& func(void (*func)(Ptr   user), Ptr   user=null, Bool immediate=true);                                                       // set function called when value has changed, with 'user' as its parameter
   T1(TYPE) SlideBar& func(void (*func)(TYPE *user), TYPE *user     , Bool immediate=true) {return T.func((void(*)(Ptr))func,  user, immediate);} // set function called when value has changed, with 'user' as its parameter
   T1(TYPE) SlideBar& func(void (*func)(TYPE &user), TYPE &user     , Bool immediate=true) {return T.func((void(*)(Ptr))func, &user, immediate);} // set function called when value has changed, with 'user' as its parameter

   virtual SlideBar& desc(C Str &desc);   C Str& desc()C {return super::desc();} // set/get description

   SlideBar& focusable(Bool on);   Bool focusable()C {return _focusable;} // set/get if can catch keyboard focus, default=true

   // operations
   virtual SlideBar& rect(C Rect &rect );   C Rect& rect()C {return super::rect();} // set/get rectangle
   virtual SlideBar& move(C Vec2 &delta);                                           // move by delta

   SlideBar& scroll   (Flt delta       , Bool immediate=false); // scroll by delta
   SlideBar& scrollTo (Flt pos         , Bool immediate=false); // scroll to pos
   SlideBar& scrollFit(Flt min, Flt max, Bool immediate=false); // scroll to fit min..max range
   SlideBar& scrollEnd(                  Bool immediate=false); // scroll to end

   SlideBar& scrollOptions(Flt relative=0.5f, Flt base=0, Bool immediate=false, Flt button_speed=1.5f); // set scrolling options, 'relative'=amount of scrolling using the mouse wheel relative to slidebar 'length' (0..Inf, default=1), 'base'=constant amount of scrolling using mouse wheel (0..Inf, default=0), 'immediate'=if mouse wheel scrolling is immediate or smooth, 'button_speed'=speed of scrolling upon pressing the left/up/right/down buttons

   SlideBar& removeSideButtons(); // remove side buttons (left/up and right/down) leaving only the middle button

   // main
   virtual GuiObj* test  (C GuiPC &gpc, C Vec2 &pos, GuiObj* &mouse_wheel); // test if 'pos' screen position intersects with the object, by returning pointer to object or its children upon intersection and null in case no intersection, 'mouse_wheel' may be modified upon intersection either to the object or its children or null
   virtual void    update(C GuiPC &gpc); // update object
   virtual void    draw  (C GuiPC &gpc); // draw   object

#if EE_PRIVATE
   void      zero            ();
   void      setButtonSubType();
   void      setParams       ();
   void      setButtonRect   ();
   SlideBar& setOffset       (Flt offset, Bool stop=true, SET_MODE mode=SET_DEFAULT);
   void      call            ();
#endif

  ~SlideBar() {del();}
   SlideBar();

#if !EE_PRIVATE
private:
#endif
   Bool       _scroll_immediate, _scroll, _vertical, _usable, _focusable, _func_immediate;
   Flt        _scroll_to, _offset, _length, _length_total, _scroll_mul, _scroll_add, _scroll_button, _button_size;
   Ptr        _func_user;
   void     (*_func)(Ptr user);
   GuiSkinPtr _skin;

protected:
   virtual Bool save(File &f, CChar *path=null)C;
   virtual Bool load(File &f, CChar *path=null) ;

   NO_COPY_CONSTRUCTOR(SlideBar);
#if EE_PRIVATE
   friend struct Region;   friend struct TextBox;
#endif
};
/******************************************************************************/