Add Pixmap capability to Fl_Dial.

FL/Fl_Dial.H

@@ -22,13 +22,20 @@
 #pragma once
 
 #include <FL/Fl_Dial_Base.H>
+#include <FL/Fl_Image.H>
+#include <FL/Fl_Group.H>
+#include <FL/Fl_Window.H>
 
 class Fl_Dial : public Fl_Dial_Base
 {
     static int _default_style;
+    static Fl_Image *_default_image;
 
     int _scaleticks;
 
+    Fl_Image *_pixmap;
+    int _last_pixmap_index;
+
     void draw_knob ( void );
     void draw_scale ( int ox,  int oy,  int side );
     void draw_cursor ( int ox,  int oy,  int sidei );
@@ -58,15 +65,27 @@ public:
         { 
             Fl_Dial_Base::type( n );
         }
-    
+
+    virtual void value_damage ( void )
+        {
+        if ( window() )
+            window()->damage( FL_DAMAGE_ALL, x(), y(), w(), h() );
+        }
+
     static void default_style ( int n ) { Fl_Dial::_default_style = n; }
+    static void default_image ( Fl_Image *i ) { Fl_Dial::_default_image = i; }
+
+    void pixmap ( Fl_Image *i ) { _pixmap = i; }
+
+    Fl_Image* pixmap ( void ) { return _pixmap; }
 
     enum 
     {
         DEFAULT,
         BURNISHED_DIAL,
         ARC_DIAL,
-        PLASTIC_DIAL
+        PLASTIC_DIAL,
+        PIXMAP_DIAL
     };
 
 
@@ -75,6 +94,9 @@ public:
         {
             _scaleticks = 12;
             
+            _pixmap = 0;
+            _last_pixmap_index = -1;
+
             box( FL_NO_BOX );
             type( DEFAULT );
         }

src/Fl_Dial.cxx

@@ -26,7 +26,10 @@
 #include <math.h>
 #include <algorithm>
 
+#include <FL/Fl_Shared_Image.H>
+
 int Fl_Dial::_default_style = Fl_Dial::PLASTIC_DIAL;
+Fl_Image *Fl_Dial::_default_image = 0;
 
 /** This simple box is suitable for use with knob-type widgets. It
  * comprises a border with shadow, and a cap with glare-lines akin
@@ -137,6 +140,56 @@ Fl_Dial::draw ( void )
 
     double angle = ( angle2() - angle1() ) * ( value() - minimum()) / ( maximum() - minimum() ) + angle1();
 
+  if ( type() == PIXMAP_DIAL )
+    {
+        Fl_Image *im = pixmap();
+
+        if ( !im )
+            im = Fl_Dial::_default_image;
+  
+        if ( im )
+        {
+
+            fl_push_clip( x(), y(), w(), h() );
+
+            const int knob_width = im->h();
+            const int frames = im->w() / im->h();
+
+            const int index = knob_width * (int)( ( frames - 1 ) * ( value() - minimum()) / ( maximum() - minimum() ));
+
+            /* if ( ( damage() == FL_DAMAGE_ALL ) || */
+            /*      ( ( damage() & FL_DAMAGE_EXPOSE ) && */
+            /*        index != _last_pixmap_index ) ) */
+            {
+
+                /* FIXME: Why doesn't this work? */
+                /* if ( ! active_r() ) */
+                /* { */
+                /*     im->inactive(); */
+                /* } */
+
+                im->draw( x() + ( w() / 2 ) - ( knob_width / 2 ),
+                          y() + ( h() / 2 ) - ( knob_width / 2 ),
+                          knob_width,
+                          knob_width,
+                          index,
+                          0 );
+
+                
+                _last_pixmap_index = index;
+            }
+
+            fl_pop_clip();
+        }
+        else
+        {
+            /* missing image... */
+        }
+
+        return;
+
+    }
+
     if ( type() == ARC_DIAL )
     {
         /* fl_line_style( FL_SOLID, 0 ); */