fix for newer version of FLTK, which do not allow make_current() in draw()

(we now just redraw the whole widget everytime, instead of doing progressive drawing)

Fltk/colorbarWindow.cpp

@@ -78,8 +78,6 @@ void colorbarWindow::redraw_range(int a, int b)
   int intensity = 0;
   double H, S, V;
 
-  make_current();
-
   if(a < 0)
     a = 0;
   if(b >= ct->size)
@@ -250,8 +248,6 @@ void colorbarWindow::redraw_marker()
   char str[50];
   double val;
 
-  make_current();
-
   y0 = marker_y;
   y1 = h() - 1;
 
@@ -571,7 +567,6 @@ int colorbarWindow::handle(int event)
     if(move_marker) {
       // changing marker position
       marker_pos = entry;
-      redraw_marker();
     }
     else {
       // changing color graph
@@ -613,14 +608,10 @@ int colorbarWindow::handle(int event)
         }
         ct->table[i] = CTX::instance()->packColor(red, green, blue, alpha);
       }
-      // redraw the color curves
-      if(pentry < entry)
-        redraw_range(pentry - 1, entry + 1);
-      else
-        redraw_range(entry - 1, pentry + 1);
       pentry = entry;
       *viewchanged = true;
     }
+    redraw();
     return 1;
   }