Improve theme-level background image support.

FL/Fl.H

@@ -275,6 +275,8 @@ public:
     See void scheme(const char *name) 
   */
   static int reload_scheme(); // platform dependent
+
+  static void scheme_bg ( Fl_Image *i ) { scheme_bg_ = i; }
   static int scrollbar_size();
   static void scrollbar_size(int W);
 

FL/Fl_Image.H

@@ -176,6 +176,9 @@ class FL_EXPORT Fl_RGB_Image : public Fl_Image {
   friend class Fl_Quartz_Graphics_Driver;
   friend class Fl_GDI_Graphics_Driver;
   friend class Fl_Xlib_Graphics_Driver;
+#if FLTK_HAVE_CAIRO
+  friend class Fl_Cairo_Graphics_Driver;
+#endif
 public:
 
   const uchar *array;

FL/Fl_Overlay_Window.H

@@ -45,6 +45,7 @@
   overlay will blink if you change the image in the window.
 */
 class FL_EXPORT Fl_Overlay_Window : public Fl_Double_Window {
+protected:
   virtual void draw_overlay() = 0;
 public:
   void flush();

src/Fl.cxx

@@ -1703,14 +1703,6 @@ void Fl_Widget::damage(uchar fl, int X, int Y, int W, int H) {
   Fl::damage(FL_DAMAGE_CHILD);
 }
 void Fl_Window::flush() {
-
-    if ( ! i->cc )
-    {
-        i->cs = Fl::cairo_create_surface( i->xid, w(), h() );
-        i->cc = cairo_create( i->cs );
-        Fl::cairo_make_current( i->cs, i->cc );
-    }
-
   draw();
 
 #if FLTK_HAVE_CAIRO

src/Fl_get_system_colors.cxx

@@ -276,12 +276,6 @@ int Fl::scheme(const char *s) {
 int Fl::reload_scheme() {
     Fl_Window *win;
 
-    // Use the standard FLTK look-n-feel...
-    if (scheme_bg_) {
-        delete scheme_bg_;
-        scheme_bg_ = (Fl_Image *)0;
-    }
-  
     set_boxtype(FL_UP_FRAME,        fl_up_frame, D1, D1, D2, D2);
     set_boxtype(FL_DOWN_FRAME,      fl_down_frame, D1, D1, D2, D2);
     set_boxtype(FL_THIN_UP_FRAME,   fl_thin_up_frame, 1, 1, 2, 2);
@@ -299,8 +293,9 @@ int Fl::reload_scheme() {
 
 // Set (or clear) the background tile for all windows...
     for (win = first_window(); win; win = next_window(win)) {
-        win->labeltype(scheme_bg_ ? FL_NORMAL_LABEL : FL_NO_LABEL);
-        win->align(FL_ALIGN_CENTER | FL_ALIGN_INSIDE | FL_ALIGN_CLIP);
+//        win->labeltype(scheme_bg_ ? FL_NORMAL_LABEL : FL_NO_LABEL);
+//        win->align(FL_ALIGN_CENTER | FL_ALIGN_INSIDE | FL_ALIGN_CLIP | FL_ALIGN_IMAGE_BACKDROP );
+        win->align( FL_ALIGN_IMAGE_BACKDROP );
         win->image(scheme_bg_);
         win->redraw();
     }

src/Fl_x.cxx

@@ -1691,6 +1691,7 @@ Fl_X* Fl_X::set_xid(Fl_Window* win, Window winxid) {
   xp->setwindow(win);
   xp->next = Fl_X::first;
   xp->region = 0;
+  xp->wait_for_expose = 0;
 //  xp->backbuffer_bad = 1;
   Fl_X::first = xp;
   if (win->modal()) {Fl::modal_ = win; fl_fix_focus();}
@@ -2007,21 +2008,20 @@ static inline int can_boxcheat(uchar b) {return (b==1 || ((b&2) && b<=15));}
 void Fl_Window::show() {
   image(Fl::scheme_bg_);
   if (Fl::scheme_bg_) {
-    labeltype(FL_NORMAL_LABEL);
-    align(FL_ALIGN_CENTER | FL_ALIGN_INSIDE | FL_ALIGN_CLIP);
+//    labeltype(FL_NORMAL_LABEL);
+      align(FL_ALIGN_IMAGE_BACKDROP);
   } else {
     labeltype(FL_NO_LABEL);
   }
 
-
-
   Fl_Tooltip::exit(this);
   if (!shown()) {
     fl_open_display();
-    // Don't set background pixel for double-buffered windows...
-    if (type() == FL_WINDOW && can_boxcheat(box())) {
-      fl_background_pixel = int(fl_xpixel(color()));
-    }
+   
+ /* // Don't set background pixel for double-buffered windows... */
+ /*    if (type() == FL_WINDOW && can_boxcheat(box())) { */
+ /*      fl_background_pixel = int(fl_xpixel(color())); */
+ /*    } */
 
     Fl_X::make_xid(this);
   } else {