added wxWindow::IsDoubleBuffered() and improve wxBufferedDC (patch 1565330)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@41810 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

build/bakefiles/files.bkl

@@ -569,6 +569,7 @@ IMPORTANT: please read docs/tech/tn0016.txt before modifying this file!
     src/common/ctrlsub.cpp
     src/common/datacmn.cpp
     src/common/dcbase.cpp
+    src/common/dcbufcmn.cpp
     src/common/dlgcmn.cpp
     src/common/dndcmn.cpp
     src/common/dobjcmn.cpp

docs/changes.txt

@@ -76,6 +76,7 @@ All (GUI):
   consistency with wxRichTextCtrl.
 - wxRichTextCtrl: fixed range out-by-one bug to be consistent with wxTextCtrl API,
   fixed some attribute bugs and added wxRichTextStyleComboCtrl.
+- Added wxWindow::IsDoubleBuffered()
 
 wxMSW:
 

docs/latex/wx/window.tex

@@ -1495,6 +1495,19 @@ to the dialog via validators.
 Resets the cached best size value so it will be recalculated the next time it is needed.
 
 
+\membersection{wxWindow::IsDoubleBuffered}\label{wxwindowisdoublebuffered}
+
+\constfunc{virtual bool}{IsDoubleBuffered}{\void}
+
+Returns \true if the window contents is double-buffered by the system, i.e. if
+any drawing done on the window is really done on a temporary backing surface
+and transferred to the screen all at once later.
+
+\wxheading{See also}
+
+\helpref{wxBufferedDC}{wxbuffereddc}
+
+
 \membersection{wxWindow::IsEnabled}\label{wxwindowisenabled}
 
 \constfunc{virtual bool}{IsEnabled}{\void}

include/wx/cocoa/window.h

@@ -199,6 +199,8 @@ public:
     virtual bool Close( bool force = false );
     virtual bool Show( bool show = true );
     virtual bool Enable( bool enable = true );
+
+    virtual bool IsDoubleBuffered() const { return true; }
 };
 
 #endif // __WX_COCOA_WINDOW_H__

include/wx/combo.h

@@ -434,9 +434,6 @@ protected:
     virtual void DoSetToolTip( wxToolTip *tip );
 #endif
 
-    // Used by OnPaints of derived classes
-    wxBitmap& GetBufferBitmap(const wxSize& sz) const;
-
     // This is used when m_text is hidden (readonly).
     wxString                m_valueString;
 

include/wx/dc.h

@@ -134,11 +134,6 @@ public:
 
     virtual ~wxDCBase() { }
 
-#if WXWIN_COMPATIBILITY_2_6
-    wxDEPRECATED( virtual void BeginDrawing() );
-    wxDEPRECATED( virtual void EndDrawing() );
-#endif // WXWIN_COMPATIBILITY_2_6
-
     // graphic primitives
     // ------------------
 
@@ -387,6 +382,12 @@ public:
     virtual void StartPage() { }
     virtual void EndPage() { }
 
+#if WXWIN_COMPATIBILITY_2_6
+    wxDEPRECATED( void BeginDrawing() );
+    wxDEPRECATED( void EndDrawing() );
+#endif // WXWIN_COMPATIBILITY_2_6
+
+
     // set objects to use for drawing
     // ------------------------------
 
@@ -503,20 +504,20 @@ public:
     // accessors and setters
     // ---------------------
 
-    int GetBackgroundMode() const { return m_backgroundMode; }
-    const wxBrush&  GetBackground() const { return m_backgroundBrush; }
-    const wxBrush&  GetBrush() const { return m_brush; }
-    const wxFont&   GetFont() const { return m_font; }
-    const wxPen&    GetPen() const { return m_pen; }
+    virtual int GetBackgroundMode() const { return m_backgroundMode; }
+    virtual const wxBrush&  GetBackground() const { return m_backgroundBrush; }
+    virtual const wxBrush&  GetBrush() const { return m_brush; }
+    virtual const wxFont&   GetFont() const { return m_font; }
+    virtual const wxPen&    GetPen() const { return m_pen; }
 
-    const wxColour& GetTextForeground() const { return m_textForegroundColour; }
-    const wxColour& GetTextBackground() const { return m_textBackgroundColour; }
+    virtual const wxColour& GetTextForeground() const { return m_textForegroundColour; }
+    virtual const wxColour& GetTextBackground() const { return m_textBackgroundColour; }
     virtual void SetTextForeground(const wxColour& colour)
         { m_textForegroundColour = colour; }
     virtual void SetTextBackground(const wxColour& colour)
         { m_textBackgroundColour = colour; }
 
-    int GetMapMode() const { return m_mappingMode; }
+    virtual int GetMapMode() const { return m_mappingMode; }
     virtual void SetMapMode(int mode) = 0;
 
     virtual void GetUserScale(double *x, double *y) const
@@ -553,7 +554,7 @@ public:
 
     virtual void SetAxisOrientation(bool xLeftRight, bool yBottomUp) = 0;
 
-    int GetLogicalFunction() const { return m_logicalFunction; }
+    virtual int GetLogicalFunction() const { return m_logicalFunction; }
     virtual void SetLogicalFunction(int function) = 0;
 
 #if WXWIN_COMPATIBILITY_2_4

include/wx/dfb/window.h

@@ -109,6 +109,8 @@ public:
 
     void OnInternalIdle();
 
+    virtual bool IsDoubleBuffered() const { return true; }
+
 protected:
     // implement the base class pure virtuals
     virtual void DoClientToScreen(int *x, int *y) const;

include/wx/gtk/dc.h

@@ -94,6 +94,8 @@ public:
 
     virtual void ComputeScaleAndOrigin();
 
+    virtual GdkWindow* GetGDKWindow() const { return NULL; }
+
 protected:
     // implementation
     // --------------

include/wx/gtk/dcclient.h

@@ -99,6 +99,8 @@ public:
     virtual void SetDeviceOrigin( wxCoord x, wxCoord y );
     virtual void SetAxisOrientation( bool xLeftRight, bool yBottomUp );
 
+    virtual GdkWindow* GetGDKWindow() const { return m_window; }
+
 // protected:
     // implementation
     // --------------

include/wx/gtk/window.h

@@ -124,6 +124,7 @@ public:
 
     // currently wxGTK2-only
     void SetDoubleBuffered(bool on);
+    virtual bool IsDoubleBuffered() const;
 
     // implementation
     // --------------

include/wx/gtk1/dc.h

@@ -66,6 +66,8 @@ public:
 
     virtual void ComputeScaleAndOrigin();
 
+    virtual GdkWindow* GetGDKWindow() const { return NULL; }
+
     wxCoord XDEV2LOG(wxCoord x) const
     {
         wxCoord new_x = x - m_deviceOriginX;

include/wx/gtk1/dcclient.h

@@ -100,6 +100,8 @@ public:
     virtual wxSize GetPPI() const;
     virtual int GetDepth() const;
 
+    virtual GdkWindow* GetGDKWindow() const { return m_window; }
+
     // implementation
     // --------------
 

include/wx/gtk1/window.h

@@ -108,6 +108,8 @@ public:
     virtual void SetDropTarget( wxDropTarget *dropTarget );
 #endif // wxUSE_DRAG_AND_DROP
 
+    virtual bool IsDoubleBuffered() const { return false; }
+
     // implementation
     // --------------
 

include/wx/mac/carbon/window.h

@@ -142,6 +142,8 @@ public:
 
     bool AcceptsFocus() const;
 
+    virtual bool IsDoubleBuffered() const { return true; }
+
 public:
     static long         MacRemoveBordersFromStyle( long style ) ;
 

include/wx/msw/missing.h

@@ -126,6 +126,10 @@
 #define WS_EX_LAYOUTRTL 0x00400000
 #endif
 
+#ifndef WS_EX_COMPOSITED
+#define WS_EX_COMPOSITED 0x02000000L
+#endif
+
 #ifndef WS_EX_LAYERED
 #define WS_EX_LAYERED 0x00080000
 #endif

include/wx/msw/window.h

@@ -420,6 +420,9 @@ public:
     // check if mouse is in the window
     bool IsMouseInWindow() const;
 
+    // check if a native double-buffering applies for this window
+    virtual bool IsDoubleBuffered() const;
+
     // synthesize a wxEVT_LEAVE_WINDOW event and set m_mouseInWindow to false
     void GenerateMouseLeave();
 

include/wx/vlbox.h

@@ -287,9 +287,6 @@ private:
     // the selection bg colour
     wxColour m_colBgSel;
 
-    // double buffer
-    wxBitmap* m_doubleBuffer;
-
     DECLARE_EVENT_TABLE()
     DECLARE_NO_COPY_CLASS(wxVListBox)
     DECLARE_ABSTRACT_CLASS(wxVListBox)

include/wx/window.h

@@ -725,6 +725,9 @@ public:
         // adjust DC for drawing on this window
     virtual void PrepareDC( wxDC & WXUNUSED(dc) ) { }
 
+        // return true if the window contents is double buffered by the system
+    virtual bool IsDoubleBuffered() const { return false; }
+
         // the update region of the window contains the areas which must be
         // repainted by the program
     const wxRegion& GetUpdateRegion() const { return m_updateRegion; }

src/common/combocmn.cpp

@@ -35,7 +35,6 @@
     #include "wx/timer.h"
 #endif
 
-#include "wx/dcbuffer.h"
 #include "wx/tooltip.h"
 
 #include "wx/combo.h"
@@ -610,9 +609,6 @@ END_EVENT_TABLE()
 
 IMPLEMENT_ABSTRACT_CLASS(wxComboCtrlBase, wxControl)
 
-// Have global double buffer - should be enough for multiple combos
-static wxBitmap* gs_doubleBuffer = (wxBitmap*) NULL;
-
 void wxComboCtrlBase::Init()
 {
     m_winPopup = (wxWindow *)NULL;
@@ -737,9 +733,6 @@ wxComboCtrlBase::~wxComboCtrlBase()
     if ( HasCapture() )
         ReleaseMouse();
 
-    delete gs_doubleBuffer;
-    gs_doubleBuffer = (wxBitmap*) NULL;
-
 #if INSTALL_TOPLEV_HANDLER
     delete ((wxComboFrameEventHandler*)m_toplevEvtHandler);
     m_toplevEvtHandler = (wxEvtHandler*) NULL;
@@ -1238,19 +1231,6 @@ void wxComboCtrlBase::RecalcAndRefresh()
     }
 }
 
-wxBitmap& wxComboCtrlBase::GetBufferBitmap( const wxSize& sz ) const
-{
-    // If size is larger, recalculate double buffer bitmap
-    if ( !gs_doubleBuffer ||
-         sz.x > gs_doubleBuffer->GetWidth() ||
-         sz.y > gs_doubleBuffer->GetHeight() )
-    {
-        delete gs_doubleBuffer;
-        gs_doubleBuffer = new wxBitmap(sz.x+25,sz.y);
-    }
-    return *gs_doubleBuffer;
-}
-
 // ----------------------------------------------------------------------------
 // miscellaneous event handlers
 // ----------------------------------------------------------------------------

src/common/dcbufcmn.cpp

@@ -0,0 +1,136 @@
+/////////////////////////////////////////////////////////////////////////////
+// Name:        src/common/dcbufcmn.cpp
+// Purpose:     Buffered DC implementation
+// Author:      Ron Lee, Jaakko Salli
+// Modified by:
+// Created:     Sep-20-2006
+// RCS-ID:      $Id$
+// Copyright:   (c) wxWidgets team
+// Licence:     wxWindows licence
+/////////////////////////////////////////////////////////////////////////////
+
+// ============================================================================
+// declarations
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// headers
+// ----------------------------------------------------------------------------
+
+// For compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
+#ifdef __BORLANDC__
+    #pragma hdrstop
+#endif
+
+#ifndef WX_PRECOMP
+#endif
+
+#include "wx/dcbuffer.h"
+
+
+// ============================================================================
+// implementation
+// ============================================================================
+
+// ============================================================================
+// wxSharedDCBufferManager
+//   Helper class to free shared buffer when the app exists.
+// ============================================================================
+
+class wxSharedDCBufferManager
+{
+    friend class wxBufferedDC;
+public:
+
+    wxSharedDCBufferManager()
+    {
+        m_buffer = NULL;
+    }
+
+    ~wxSharedDCBufferManager()
+    {
+        delete m_buffer;
+    }
+
+    wxBitmap* GetBuffer(wxWindow* win, const wxSize& area)
+    {
+        int width = area.x;
+        int height = area.y;
+
+        if ( width <= 0 )
+            win->GetClientSize(&width, &height);
+
+        if ( !m_buffer ||
+             width > m_buffer->GetWidth() ||
+             height > m_buffer->GetHeight() )
+        {
+            delete m_buffer;
+
+            // Create slightly larger bitmap so we don't need to
+            // be reallocating constantly when the user enlarges
+            // the frame for the first time.
+            m_buffer = new wxBitmap(width+20, height+20);
+        }
+
+        return m_buffer;
+    }
+
+private:
+    wxBitmap*   m_buffer;
+};
+
+static wxSharedDCBufferManager gs_sharedDCBufferManager;
+
+// ============================================================================
+// wxBufferedDC
+// ============================================================================
+
+// Blits the buffer to the dc, and detaches the dc from the buffer (so it
+// can be effectively used once only).
+//
+// Usually called in the dtor or by the dtor of derived classes if the
+// BufferedDC must blit before the derived class (which may own the dc it's
+// blitting to) is destroyed.
+void wxBufferedDC::UnMask()
+{
+    if ( m_buffer )
+    {
+        wxASSERT_MSG( m_mainDc != NULL,
+                      _T("No underlying DC associated with wxBufferedDC (anymore)") );
+
+        wxDC* bufferDc = DetachDC();
+
+        wxASSERT( bufferDc->IsKindOf(CLASSINFO(wxMemoryDC)) );
+
+        wxCoord x=0, y=0;
+
+        if (m_style & wxBUFFER_CLIENT_AREA)
+            bufferDc->GetDeviceOrigin(& x, & y);
+
+        m_mainDc->Blit( 0, 0,
+                        m_buffer->GetWidth(), m_buffer->GetHeight(), bufferDc,
+                        -x, -y );
+        m_mainDc = NULL;
+        m_buffer = NULL;
+        delete bufferDc;
+    }
+}
+
+void wxBufferedDC::PrepareBuffer(wxWindow* win, const wxSize& area)
+{
+    m_buffer = gs_sharedDCBufferManager.GetBuffer(win, area);
+}
+
+void wxBufferedDC::UseBuffer()
+{
+    wxASSERT(m_buffer);
+
+    wxMemoryDC* memoryDc = new wxMemoryDC(m_mainDc);
+    memoryDc->SelectObject(*m_buffer);
+
+    AttachDC(memoryDc);
+}
+
+

src/generic/combog.cpp

@@ -201,7 +201,7 @@ void wxGenericComboCtrl::OnResize()
 void wxGenericComboCtrl::OnPaintEvent( wxPaintEvent& WXUNUSED(event) )
 {
     wxSize sz = GetClientSize();
-    wxBufferedPaintDC dc(this,GetBufferBitmap(sz));
+    wxAutoBufferedPaintDC dc(this);
 
     const wxRect& rectb = m_btnArea;
     wxRect rect = m_tcArea;

src/generic/datavgen.cpp

@@ -35,6 +35,7 @@
 #include "wx/calctrl.h"
 #include "wx/popupwin.h"
 #include "wx/renderer.h"
+#include "wx/dcbuffer.h"
 #include "wx/icon.h"
 
 //-----------------------------------------------------------------------------
@@ -682,6 +683,7 @@ wxDataViewHeaderWindow::wxDataViewHeaderWindow( wxDataViewCtrl *parent, wxWindow
     m_resizeCursor = new wxCursor( wxCURSOR_SIZEWE );
 
     wxVisualAttributes attr = wxPanel::GetClassDefaultAttributes();
+    SetBackgroundStyle( wxBG_STYLE_CUSTOM );
     SetOwnForegroundColour( attr.colFg );
     SetOwnBackgroundColour( attr.colBg );
     if (!m_hasFont)
@@ -698,7 +700,10 @@ void wxDataViewHeaderWindow::OnPaint( wxPaintEvent &WXUNUSED(event) )
     int w, h;
     GetClientSize( &w, &h );
 
-    wxPaintDC dc( this );
+    wxAutoBufferedPaintDC dc( this );
+
+    dc.SetBackground(GetBackgroundColour());
+    dc.Clear();
 
     int xpix;
     m_owner->GetScrollPixelsPerUnit( &xpix, NULL );
@@ -953,6 +958,7 @@ wxDataViewMainWindow::wxDataViewMainWindow( wxDataViewCtrl *parent, wxWindowID i
 
     m_hasFocus = false;
 
+    SetBackgroundStyle( wxBG_STYLE_CUSTOM );
     SetBackgroundColour( *wxWHITE );
 
     UpdateDisplay();
@@ -1094,7 +1100,10 @@ void wxDataViewMainWindow::ScrollWindow( int dx, int dy, const wxRect *rect )
 
 void wxDataViewMainWindow::OnPaint( wxPaintEvent &WXUNUSED(event) )
 {
-    wxPaintDC dc( this );
+    wxAutoBufferedPaintDC dc( this );
+
+    dc.SetBackground(GetBackgroundColour());
+    dc.Clear();
 
     GetOwner()->PrepareDC( dc );
 

src/generic/vlbox.cpp

@@ -64,7 +64,6 @@ void wxVListBox::Init()
     m_current =
     m_anchor = wxNOT_FOUND;
     m_selStore = NULL;
-    m_doubleBuffer = NULL;
 }
 
 bool wxVListBox::Create(wxWindow *parent,
@@ -94,7 +93,6 @@ bool wxVListBox::Create(wxWindow *parent,
 
 wxVListBox::~wxVListBox()
 {
-    delete m_doubleBuffer;
     delete m_selStore;
 }
 
@@ -360,18 +358,9 @@ void wxVListBox::OnDrawBackground(wxDC& dc, const wxRect& rect, size_t n) const
 
 void wxVListBox::OnPaint(wxPaintEvent& WXUNUSED(event))
 {
-    // If size is larger, recalculate double buffer bitmap
     wxSize clientSize = GetClientSize();
 
-    if ( !m_doubleBuffer ||
-         clientSize.x > m_doubleBuffer->GetWidth() ||
-         clientSize.y > m_doubleBuffer->GetHeight() )
-    {
-        delete m_doubleBuffer;
-        m_doubleBuffer = new wxBitmap(clientSize.x+25,clientSize.y+25);
-    }
-
-    wxBufferedPaintDC dc(this,*m_doubleBuffer);
+    wxAutoBufferedPaintDC dc(this);
 
     // the update rectangle
     wxRect rectUpdate = GetUpdateClientRect();

src/gtk/renderer.cpp

@@ -192,6 +192,10 @@ wxRendererGTK::DrawHeaderButton(wxWindow *win,
 
     GtkWidget *button = GetButtonWidget();
 
+    GdkWindow* gdk_window = dc.GetGDKWindow();
+    wxASSERT_MSG( gdk_window,
+                  wxT("cannot use wxRendererNative on wxDC of this type") );
+
     int x_diff = 0;
     if (win->GetLayoutDirection() == wxLayout_RightToLeft)
         x_diff = rect.width;
@@ -199,9 +203,7 @@ wxRendererGTK::DrawHeaderButton(wxWindow *win,
     gtk_paint_box
     (
         button->style,
-        // FIXME: I suppose GTK_PIZZA(win->m_wxwindow)->bin_window doesn't work with wxMemoryDC.
-        //   Maybe use code similar as in DrawPushButton below?
-        GTK_PIZZA(win->m_wxwindow)->bin_window,
+        gdk_window,
         flags & wxCONTROL_DISABLED ? GTK_STATE_INSENSITIVE : GTK_STATE_NORMAL,
         GTK_SHADOW_OUT,
         NULL,
@@ -220,6 +222,10 @@ wxRendererGTK::DrawTreeItemButton(wxWindow* win,
 {
     GtkWidget *tree = GetTreeWidget();
 
+    GdkWindow* gdk_window = dc.GetGDKWindow();
+    wxASSERT_MSG( gdk_window,
+                  wxT("cannot use wxRendererNative on wxDC of this type") );
+
     GtkStateType state;
     if ( flags & wxCONTROL_CURRENT )
         state = GTK_STATE_PRELIGHT;
@@ -229,13 +235,13 @@ wxRendererGTK::DrawTreeItemButton(wxWindow* win,
     int x_diff = 0;
     if (win->GetLayoutDirection() == wxLayout_RightToLeft)
         x_diff = rect.width;
-        
+
     // VZ: I don't know how to get the size of the expander so as to centre it
     //     in the given rectangle, +2/3 below is just what looks good here...
     gtk_paint_expander
     (
         tree->style,
-        GTK_PIZZA(win->m_wxwindow)->bin_window,
+        gdk_window,
         state,
         NULL,
         tree,
@@ -299,6 +305,10 @@ wxRendererGTK::DrawSplitterSash(wxWindow *win,
         return;
     }
 
+    GdkWindow* gdk_window = dc.GetGDKWindow();
+    wxASSERT_MSG( gdk_window,
+                  wxT("cannot use wxRendererNative on wxDC of this type") );
+
     wxCoord full_size = GetGtkSplitterFullSize();
 
     // are we drawing vertical or horizontal splitter?
@@ -332,7 +342,7 @@ wxRendererGTK::DrawSplitterSash(wxWindow *win,
     gtk_paint_handle
     (
         win->m_wxwindow->style,
-        GTK_PIZZA(win->m_wxwindow)->bin_window,
+        gdk_window,
         flags & wxCONTROL_CURRENT ? GTK_STATE_PRELIGHT : GTK_STATE_NORMAL,
         GTK_SHADOW_NONE,
         NULL /* no clipping */,
@@ -347,7 +357,7 @@ wxRendererGTK::DrawSplitterSash(wxWindow *win,
 }
 
 void
-wxRendererGTK::DrawDropArrow(wxWindow *win,
+wxRendererGTK::DrawDropArrow(wxWindow *WXUNUSED(win),
                              wxDC& dc,
                              const wxRect& rect,
                              int flags)
@@ -359,11 +369,9 @@ wxRendererGTK::DrawDropArrow(wxWindow *win,
     // 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;
-
-    // only doing debug-time checking here (it should
-    // probably be enough)
-    wxASSERT ( wdc.IsKindOf(CLASSINFO(wxWindowDC)) );
+    GdkWindow* gdk_window = dc.GetGDKWindow();
+    wxASSERT_MSG( gdk_window,
+                  wxT("cannot use wxRendererNative on wxDC of this type") );
 
     // draw arrow so that there is even space horizontally
     // on both sides
@@ -390,7 +398,7 @@ wxRendererGTK::DrawDropArrow(wxWindow *win,
     gtk_paint_arrow
     (
         button->style,
-        wdc.m_window,
+        gdk_window,
         state,
         flags & wxCONTROL_PRESSED ? GTK_SHADOW_IN : GTK_SHADOW_OUT,
         NULL,
@@ -416,7 +424,7 @@ wxRendererGTK::DrawComboBoxDropButton(wxWindow *win,
 }
 
 void
-wxRendererGTK::DrawCheckBox(wxWindow *win,
+wxRendererGTK::DrawCheckBox(wxWindow *WXUNUSED(win),
                             wxDC& dc,
                             const wxRect& rect,
                             int flags )
@@ -424,8 +432,9 @@ wxRendererGTK::DrawCheckBox(wxWindow *win,
     GtkWidget *button = GetCheckButtonWidget();
 
     // for reason why we do this, see DrawDropArrow
-    wxWindowDC& wdc = (wxWindowDC&)dc;
-    wxASSERT ( wdc.IsKindOf(CLASSINFO(wxWindowDC)) );
+    GdkWindow* gdk_window = dc.GetGDKWindow();
+    wxASSERT_MSG( gdk_window,
+                  wxT("cannot use wxRendererNative on wxDC of this type") );
 
     GtkStateType state;
 
@@ -441,7 +450,7 @@ wxRendererGTK::DrawCheckBox(wxWindow *win,
     gtk_paint_check
     (
         button->style,
-        wdc.m_window,
+        gdk_window,
         state,
         flags & wxCONTROL_CHECKED ? GTK_SHADOW_IN : GTK_SHADOW_OUT,
         NULL,
@@ -454,7 +463,7 @@ wxRendererGTK::DrawCheckBox(wxWindow *win,
 }
 
 void
-wxRendererGTK::DrawPushButton(wxWindow *win,
+wxRendererGTK::DrawPushButton(wxWindow *WXUNUSED(win),
                               wxDC& dc,
                               const wxRect& rect,
                               int flags)
@@ -462,8 +471,9 @@ wxRendererGTK::DrawPushButton(wxWindow *win,
     GtkWidget *button = GetButtonWidget();
 
     // for reason why we do this, see DrawDropArrow
-    wxWindowDC& wdc = (wxWindowDC&)dc;
-    wxASSERT ( wdc.IsKindOf(CLASSINFO(wxWindowDC)) );
+    GdkWindow* gdk_window = dc.GetGDKWindow();
+    wxASSERT_MSG( gdk_window,
+                  wxT("cannot use wxRendererNative on wxDC of this type") );
 
     // draw button
     GtkStateType state;
@@ -480,7 +490,7 @@ wxRendererGTK::DrawPushButton(wxWindow *win,
     gtk_paint_box
     (
         button->style,
-        wdc.m_window,
+        gdk_window,
         state,
         flags & wxCONTROL_PRESSED ? GTK_SHADOW_IN : GTK_SHADOW_OUT,
         NULL,
@@ -496,6 +506,10 @@ wxRendererGTK::DrawItemSelectionRect(wxWindow *win,
                                      const wxRect& rect,
                                      int flags )
 {
+    GdkWindow* gdk_window = dc.GetGDKWindow();
+    wxASSERT_MSG( gdk_window,
+                  wxT("cannot use wxRendererNative on wxDC of this type") );
+
     GtkStateType state;
     if (flags & wxCONTROL_SELECTED)
     {
@@ -505,7 +519,7 @@ wxRendererGTK::DrawItemSelectionRect(wxWindow *win,
             state = GTK_STATE_INSENSITIVE;
 
         gtk_paint_flat_box( win->m_wxwindow->style,
-                        GTK_PIZZA(win->m_wxwindow)->bin_window,
+                        gdk_window,
                         state,
                         GTK_SHADOW_NONE,
                         NULL,

src/gtk/window.cpp

@@ -3935,6 +3935,11 @@ void wxWindowGTK::SetDoubleBuffered( bool on )
         gtk_widget_set_double_buffered( m_wxwindow, on );
 }
 
+bool wxWindowGTK::IsDoubleBuffered() const
+{
+    return GTK_WIDGET_DOUBLE_BUFFERED( m_wxwindow );
+}
+
 void wxWindowGTK::ClearBackground()
 {
     wxCHECK_RET( m_widget != NULL, wxT("invalid window") );

src/gtk1/renderer.cpp

@@ -309,11 +309,9 @@ wxRendererGTK::DrawDropArrow(wxWindow *win,
     // 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;
-
-    // only doing debug-time checking here (it should
-    // probably be enough)
-    wxASSERT ( wdc.IsKindOf(CLASSINFO(wxWindowDC)) );
+    GdkWindow* gdk_window = dc.GetGDKWindow();
+    wxASSERT_MSG( gdk_window,
+                  wxT("cannot use wxRendererNative on wxDC of this type") );
 
     // draw arrow so that there is even space horizontally
     // on both sides
@@ -340,7 +338,7 @@ wxRendererGTK::DrawDropArrow(wxWindow *win,
     gtk_paint_arrow
     (
         button->style,
-        wdc.m_window,
+        gdk_window,
         state,
         flags & wxCONTROL_PRESSED ? GTK_SHADOW_IN : GTK_SHADOW_OUT,
         NULL,
@@ -364,8 +362,9 @@ wxRendererGTK::DrawComboBoxDropButton(wxWindow *win,
     GtkWidget *button = GetButtonWidget();
 
     // for reason why we do this, see DrawDropArrow
-    wxWindowDC& wdc = (wxWindowDC&)dc;
-    wxASSERT ( wdc.IsKindOf(CLASSINFO(wxWindowDC)) );
+    GdkWindow* gdk_window = dc.GetGDKWindow();
+    wxASSERT_MSG( gdk_window,
+                  wxT("cannot use wxRendererNative on wxDC of this type") );
 
     // draw button
     GtkStateType state;
@@ -382,7 +381,7 @@ wxRendererGTK::DrawComboBoxDropButton(wxWindow *win,
     gtk_paint_box
     (
         button->style,
-        wdc.m_window,
+        gdk_window,
         state,
         flags & wxCONTROL_PRESSED ? GTK_SHADOW_IN : GTK_SHADOW_OUT,
         NULL,

src/msw/combo.cpp

@@ -388,7 +388,7 @@ void wxComboCtrl::OnPaintEvent( wxPaintEvent& WXUNUSED(event) )
     // TODO: Convert drawing in this function to Windows API Code
 
     wxSize sz = GetClientSize();
-    wxBufferedPaintDC dc(this,GetBufferBitmap(sz));
+    wxAutoBufferedPaintDC dc(this);
 
     const wxRect& rectb = m_btnArea;
     wxRect rect = m_tcArea;

src/msw/window.cpp

@@ -3950,6 +3950,20 @@ bool wxWindowMSW::HandlePower(WXWPARAM WXUNUSED_IN_WINCE(wParam),
 #endif
 }
 
+bool wxWindowMSW::IsDoubleBuffered() const
+{
+    const wxWindow* wnd = this;
+
+    while ( wnd )
+    {
+        if ( ::GetWindowLong((HWND)wnd->GetHWND(), GWL_EXSTYLE) & WS_EX_COMPOSITED )
+            return true;
+        wnd = wnd->GetParent();
+    }
+
+    return false;
+}
+
 // ---------------------------------------------------------------------------
 // owner drawn stuff
 // ---------------------------------------------------------------------------