#include <gtk/gtk.h>
 #include "wx/gtk1/win_gtk.h"
-
-#include "wx/dcclient.h"
+#include "wx/gtk1/dcclient.h"
 
 // RR: After a correction to the orientation of the sash
 //     this doesn't seem to be required anymore and it
         NULL,
         button,
         "button",
-        dc.XLOG2DEV(rect.x) -1, rect.y -1, rect.width +2, rect.height +2
+        dc.LogicalToDeviceX(rect.x) -1, rect.y -1, rect.width +2, rect.height +2
     );
 }
 
 
 void
 wxRendererGTK::DrawSplitterSash(wxWindow *win,
-                                wxDC& dc,
+                                wxDC& WXUNUSED(dc),
                                 const wxSize& size,
                                 wxCoord position,
                                 wxOrientation orient,
 }
 
 void
-wxRendererGTK::DrawDropArrow(wxWindow *win,
+wxRendererGTK::DrawDropArrow(wxWindow *WXUNUSED(win),
                              wxDC& dc,
                              const wxRect& rect,
                              int flags)
     // work for wxMemoryDC. So that is why we assume wxDC
     // is wxWindowDC (wxClientDC, wxMemoryDC and wxPaintDC
     // are derived from it) and use its m_window.
-    wxWindowDC& wdc = (wxWindowDC&)dc;
+    wxWindowDCImpl * const impl = wxDynamicCast(dc.GetImpl(), wxWindowDCImpl);
+    wxCHECK_RET( impl, "must have a window DC" );
 
-    // only doing debug-time checking here (it should
-    // probably be enough)
-    wxASSERT ( wdc.IsKindOf(CLASSINFO(wxWindowDC)) );
+    GdkWindow* gdk_window = impl->GetGDKWindow();
 
     // draw arrow so that there is even space horizontally
     // on both sides
     gtk_paint_arrow
     (
         button->style,
-        wdc.m_window,
+        gdk_window,
         state,
         flags & wxCONTROL_PRESSED ? GTK_SHADOW_IN : GTK_SHADOW_OUT,
         NULL,
     GtkWidget *button = GetButtonWidget();
 
     // for reason why we do this, see DrawDropArrow
-    wxWindowDC& wdc = (wxWindowDC&)dc;
-    wxASSERT ( wdc.IsKindOf(CLASSINFO(wxWindowDC)) );
+    wxWindowDCImpl * const impl = wxDynamicCast(dc.GetImpl(), wxWindowDCImpl);
+    wxCHECK_RET( impl, "must have a window DC" );
+
+    GdkWindow* gdk_window = impl->GetGDKWindow();
 
     // draw button
     GtkStateType state;
     gtk_paint_box
     (
         button->style,
-        wdc.m_window,
+        gdk_window,
         state,
         flags & wxCONTROL_PRESSED ? GTK_SHADOW_IN : GTK_SHADOW_OUT,
         NULL,