Fl_Panzoomer: Get rid of callback in favor of virtual method and inheritance.

FL/Fl_Panzoomer.H

@@ -26,11 +26,6 @@ class FL_EXPORT Fl_Panzoomer : public Fl_Valuator
 {
 protected:
 
-    typedef void (draw_thumbnail_view_callback_t)( int X,int Y,int W,int H,void *v );
-
-    draw_thumbnail_view_callback_t *_draw_thumbnail_view_callback;
-    void *_draw_thumbnail_view_userdata;
-
     int _zoom;
     bool _zoom_changed;
     int _zoom_min;
@@ -43,19 +38,32 @@ protected:
      * between 0-1. */
     double _ysize, _xsize;
 
+protected:
+
+    virtual void draw_cursor ( int X, int Y, int W, int H );
+    /* override this method to draw a thumbnail background... */
+    virtual void draw_background ( int X, int Y, int W, int H );
+    virtual void draw ( int X, int Y, int W, int H );
+    virtual int handle ( int m, int X, int Y, int W, int H );
+    void cursor_bounds ( int &cx, int &cy, int &cw, int &ch ) const;
+
 public:
 
+    virtual void draw ( void );
+    virtual int handle ( int m );
+
     Fl_Panzoomer ( int X, int Y, int W, int H, const char *L=0 );
     virtual ~Fl_Panzoomer ( ) { }
 
-    virtual void draw ( void );
-    virtual int handle ( int m );
 
     /* these behave like Fl_Scrollbar::value() */
     /* first and total are the bounds, size is the size of the window,
      * and pos is the leftmost edge. */
     int x_value ( int pos, int size, int first, int total )
         {
+            if ( pos + size > first + total )
+                total = pos+size-first;
+
             _xmin = first;
             _xmax = total;
             _xpos = pos;
@@ -68,11 +76,15 @@ public:
 
     int y_value ( int pos, int size, int first, int total )
         {
+            if ( pos + size > first + total )
+                total = pos+size-first;
+
             _ymin = first;
             _ymax = total;
             _ypos = pos;
             _ysize = size;
 
+
             redraw();
 
             return pos;
@@ -83,7 +95,6 @@ public:
     void x_value ( double v );
     void y_value ( double v );
 
-    void cursor_bounds ( int &cx, int &cy, int &cw, int &ch ) const;
 
     bool zoom_changed ( void ) const { return _zoom_changed; }
     double zoom ( void ) const { return _zoom; }
@@ -91,15 +102,8 @@ public:
 
     void zoom_range ( int zmin, int zmax ) { _zoom_min = zmin; _zoom_max = zmax; }
 
-    void zoom_in ( void ) { int z = _zoom; zoom( _zoom + 1 ); if ( z != _zoom ) do_callback(); }
-    void zoom_out ( void ) { int z = _zoom; zoom( _zoom - 1 ); if ( z != _zoom ) do_callback(); }
-
-    /* set this callback if you want to display a thumbnail view of the canvas being scrolled */
-    void draw_thumbnail_view_callback( draw_thumbnail_view_callback_t *cb, void *v )
-        {
-            _draw_thumbnail_view_callback = cb;
-            _draw_thumbnail_view_userdata = v;
-        }
+    void zoom_in ( void ) { int z = _zoom; zoom( _zoom - 1 ); if ( z != _zoom ) do_callback(); }
+    void zoom_out ( void ) { int z = _zoom; zoom( _zoom + 1 ); if ( z != _zoom ) do_callback(); }
 };
 
 #endif

src/Fl_Panzoomer.cxx

@@ -88,25 +88,41 @@ Fl_Panzoomer::zoom ( int v )
 void
 Fl_Panzoomer::draw ( void )
 {
-    type( FL_HORIZONTAL );
+    draw(x(),y(),w(),h());
+}
+
+void
+Fl_Panzoomer::draw ( int X, int Y, int W, int H )
+{
+    fl_draw_box( box(), X,Y,W,H,color());
 
-    fl_draw_box( box(), x(),y(),w(),h(), color());
-//    fl_rectf( x(),y(),w(),h(), color() );
+    X += Fl::box_dx( box() );
+    Y += Fl::box_dy( box() );
+    W -= Fl::box_dw( box() );
+    H -= Fl::box_dh( box() );
 
-    fl_push_clip( x(), y(), w(), h());
+    fl_push_clip( X,Y,W,H );
 
-    int X,Y,W,H;
-    
-    X = x() + Fl::box_dx( box() );
-    Y = y() + Fl::box_dy( box() );
-    W = w() - Fl::box_dw( box() );
-    H = h() - Fl::box_dh( box() );
+    draw_background( X,Y,W,H );
+    draw_cursor( X,Y,W,H );
     
-    if ( _draw_thumbnail_view_callback )
-        _draw_thumbnail_view_callback( X,Y,W,H, _draw_thumbnail_view_userdata );
+    fl_pop_clip();
+
+    draw_label();
+}
+
+void
+Fl_Panzoomer::draw_background ( int X, int Y, int W, int H )
+{
+}
 
+void
+Fl_Panzoomer::draw_cursor ( int X, int Y, int W, int H )
+{
     int cx,cy,cw,ch;
 
+    cx = X; cy = Y; cw = W; ch = H;
+
     cursor_bounds( cx,cy,cw,ch );
 
     fl_rectf( cx,cy,cw,ch,
@@ -114,10 +130,6 @@ Fl_Panzoomer::draw ( void )
 
     fl_rect( cx,cy,cw,ch,
               fl_color_add_alpha( FL_WHITE, 80 ));
-    
-    fl_pop_clip();
-
-    draw_label();
 }
 
 void
@@ -125,10 +137,10 @@ Fl_Panzoomer::cursor_bounds ( int &cx, int &cy, int &cw, int &ch ) const
 {
     int X,Y,W,H;
     
-    X = x() + Fl::box_dx( box() );
-    Y = y() + Fl::box_dy( box() );
-    W = w() - Fl::box_dw( box() );
-    H = h() - Fl::box_dh( box() );
+    X = cx;
+    Y = cy;
+    W = cw;
+    H = ch;
 
     double hval;
     if ( _xmin == _xmax )
@@ -160,11 +172,22 @@ Fl_Panzoomer::cursor_bounds ( int &cx, int &cy, int &cw, int &ch ) const
 
 int
 Fl_Panzoomer::handle ( int m )
+{
+    return handle( m, x(),y(),w(),h());
+}
+
+int
+Fl_Panzoomer::handle ( int m, int X, int Y, int W, int H )
 {
     static int xoffset;
     static int yoffset;
     static bool drag;
 
+    X += Fl::box_dx( box() );
+    Y += Fl::box_dy( box() );
+    W -= Fl::box_dw( box() );
+    H -= Fl::box_dh( box() );
+
     switch ( m )
     {
         case FL_ENTER:
@@ -174,6 +197,8 @@ Fl_Panzoomer::handle ( int m )
         {
             int cx,cy,cw,ch;
 
+            cx = X; cy = Y; cw = W; ch = H;
+            
             cursor_bounds( cx,cy,cw,ch );
 
             xoffset = Fl::event_x() - cx;
@@ -188,13 +213,15 @@ Fl_Panzoomer::handle ( int m )
         case FL_DRAG:
         {
             int cx,cy,cw,ch;
+
+            cx = X; cy = Y; cw = W; ch = H;
             
             cursor_bounds( cx,cy,cw,ch );
             
             if ( drag )
             {
-                x_value((((double)Fl::event_x() - x() - xoffset) / w()) * _xmax);
-                y_value( (((double)Fl::event_y() - y() - yoffset) / h()) * _ymax );
+                x_value((((double)Fl::event_x() - X - xoffset) / W) * _xmax);
+                y_value( (((double)Fl::event_y() - Y - yoffset) / H) * _ymax );
                 
                 if ( when() & FL_WHEN_CHANGED )
                     do_callback();
@@ -215,7 +242,7 @@ Fl_Panzoomer::handle ( int m )
             }
             else if (!Fl::event_alt() && !Fl::event_shift())
             {
-                y_value( _ypos + ( (double)d*5 / h() ) * _ymax );
+                y_value( _ypos + ( (double)d*5 / H ) * _ymax );
                 
                 if ( when() & FL_WHEN_CHANGED )
                     do_callback();
@@ -237,6 +264,47 @@ Fl_Panzoomer::handle ( int m )
             
             return 1;
         }
+        case FL_KEYBOARD: 
+        {
+            if ( Fl::event_shift() || Fl::event_ctrl() || Fl::event_alt() )
+                return 0;
+
+            double xv = _xpos;
+            double yv = _ypos;
+
+            /* FIXME: hack */
+            int xls = _xsize / 50;
+            int yls = _ysize / 50;
+
+            switch ( Fl::event_key() )
+            {
+                case FL_Up:
+                    yv -= yls;
+                    break;
+                case FL_Down:
+                    yv += yls;
+                    break;
+                case FL_Left:
+                    xv -= xls;
+                    break;
+                case FL_Right:
+                    xv += xls;
+                    break;
+                default:
+                    return 0;
+            }
+            
+            x_value( xv );
+            y_value( yv );
+
+            do_callback();
+
+            redraw();
+
+            return 1;
+
+            break;
+        }
     }
 
     return 0;