Gdk::Bitmap 1 bit x pixel drawing

[angelo dureghello <angelo70 gmail com>]

Hello all,

i'm trying to draw a rectangle on a Gdk::Bitmap, to have the mask for a 
transparent window.

In any way, i can't draw on the Bitmap. Using draw_rectangle don't 
produce any change on the Bitmap data. Even if i ude set_rgb_fg_color to 
white, nothing change.

If i put the pixel to 1, setting bytes to 0xff, it works.

The Pango::Layout is drawed correctly, even on the Bitmap.

This is my code:

bool WTransp::on_expose_event  (GdkEventExpose* ev)
{
   int w, h;
   int size;

   get_size(w, h);

   size = (w * h) >> 3;

   char  * data = new char[1+size];

   memset(data, 0x00, 1+size);

   Glib::RefPtr<Gdk::Bitmap> mask = Gdk::Bitmap::create(data, w, h);

   delete[] data;


   Glib::RefPtr<Gdk::GC>       gc = Gdk::GC::create(mask);

   gc->set_rgb_fg_color(Gdk::Color("white"));

   mask->draw_layout         (gc,
                                       20,
                                       20,
                                       m_rploTxt);

   mask->draw_rectangle      (gc,
                                       false,
                                       0,
                                       0,
                                       10,
                                       10
                                   );

   get_window()->draw_layout (get_style()->get_white_gc(),
                                       20,
                                       20,
                                       m_rploTxt);

   get_window()->draw_rectangle  (get_style()->get_white_gc(),
                                       false,
                                       0,
                                       0,
                                       10,
                                       10
                                   );

   // Mask out transparent parts of the pixmap.
   shape_combine_mask(mask, 0, 0);

   return false;
}


If any help, thanks Angelo.