// Name: wx/dcbuffer.h
// Purpose: wxBufferedDC class
// Author: Ron Lee <ron@debian.org>
-// Modified by:
+// Modified by: Vadim Zeitlin (refactored, added bg preservation)
// Created: 16/03/02
// RCS-ID: $Id$
// Copyright: (c) Ron Lee
#ifndef _WX_DCBUFFER_H_
#define _WX_DCBUFFER_H_
-#if defined(__GNUG__) && !defined(__APPLE__)
-#pragma interface "dcbuffer.h"
+#include "wx/dcmemory.h"
+#include "wx/dcclient.h"
+#include "wx/window.h"
+
+// Split platforms into two groups - those which have well-working
+// double-buffering by default, and those which do not.
+#if defined(__WXMAC__) || defined(__WXGTK20__) || defined(__WXDFB__)
+ #define wxALWAYS_NATIVE_DOUBLE_BUFFER 1
+#else
+ #define wxALWAYS_NATIVE_DOUBLE_BUFFER 0
#endif
-#include "wx/dcmemory.h"
+// ----------------------------------------------------------------------------
+// Double buffering helper.
+// ----------------------------------------------------------------------------
+
+// Assumes the buffer bitmap covers the entire scrolled window,
+// and prepares the window DC accordingly
+#define wxBUFFER_VIRTUAL_AREA 0x01
-// ==============================================================
-// Double buffering helper.
-// --------------------------------------------------------------
+// Assumes the buffer bitmap only covers the client area;
+// does not prepare the window DC
+#define wxBUFFER_CLIENT_AREA 0x02
class WXDLLEXPORT wxBufferedDC : public wxMemoryDC
{
+public:
+ // Default ctor, must subsequently call Init for two stage construction.
+ wxBufferedDC()
+ : m_dc(NULL),
+ m_buffer(NULL),
+ m_style(0)
+ {
+ }
+
+ // Construct a wxBufferedDC using a user supplied buffer.
+ wxBufferedDC(wxDC *dc,
+ wxBitmap& buffer = wxNullBitmap,
+ int style = wxBUFFER_CLIENT_AREA)
+ : m_dc(NULL), m_buffer(NULL)
+ {
+ Init(dc, buffer, style);
+ }
+
+ // Construct a wxBufferedDC with an internal buffer of 'area'
+ // (where area is usually something like the size of the window
+ // being buffered)
+ wxBufferedDC(wxDC *dc, const wxSize& area, int style = wxBUFFER_CLIENT_AREA)
+ : m_dc(NULL), m_buffer(NULL)
+ {
+ Init(dc, area, style);
+ }
+
+ // The usually desired action in the dtor is to blit the buffer.
+ virtual ~wxBufferedDC()
+ {
+ if ( m_dc )
+ UnMask();
+ }
+
+ // These reimplement the actions of the ctors for two stage creation
+ void Init(wxDC *dc,
+ wxBitmap& buffer = wxNullBitmap,
+ int style = wxBUFFER_CLIENT_AREA)
+ {
+ InitCommon(dc, style);
+
+ m_buffer = &buffer;
+
+ UseBuffer();
+ }
+
+ void Init(wxDC *dc, const wxSize &area, int style = wxBUFFER_CLIENT_AREA)
+ {
+ InitCommon(dc, style);
+
+ UseBuffer(area.x, area.y);
+ }
+
+ // 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 UnMask()
+ {
+ wxCHECK_RET( m_dc, _T("no underlying wxDC?") );
+ wxASSERT_MSG( m_buffer && m_buffer->IsOk(), _T("invalid backing store") );
+
+ wxCoord x = 0,
+ y = 0;
+
+ if ( m_style & wxBUFFER_CLIENT_AREA )
+ GetDeviceOrigin(&x, &y);
+
+ m_dc->Blit(0, 0, m_buffer->GetWidth(), m_buffer->GetHeight(),
+ this, -x, -y );
+ m_dc = NULL;
+ }
+
+ // Set and get the style
+ void SetStyle(int style) { m_style = style; }
+ int GetStyle() const { return m_style; }
+
private:
+ // common part of Init()s
+ void InitCommon(wxDC *dc, int style)
+ {
+ wxASSERT_MSG( !m_dc, _T("wxBufferedDC already initialised") );
- // Without the existence of a wxNullDC, this must be
- // a pointer, else it could probably be a reference.
+ m_dc = dc;
+ m_style = style;
- wxDC *m_dc;
- wxBitmap m_buffer;
+ // inherit the same layout direction as the original DC
+ if (dc && dc->IsOk())
+ SetLayoutDirection(dc->GetLayoutDirection());
+ }
-public:
+ // check that the bitmap is valid and use it
+ void UseBuffer(wxCoord w = -1, wxCoord h = -1);
- // Default ctor, must subsequently call Init for
- // two stage construction.
+ // the underlying DC to which we copy everything drawn on this one in
+ // UnMask()
+ //
+ // NB: Without the existence of a wxNullDC, this must be a pointer, else it
+ // could probably be a reference.
+ wxDC *m_dc;
- wxBufferedDC()
- : m_dc( 0 )
- {}
+ // the buffer (selected in this DC), initially invalid
+ wxBitmap *m_buffer;
+
+ // the buffering style
+ int m_style;
- // Construct a wxBufferedDC using a user supplied buffer.
+ DECLARE_DYNAMIC_CLASS(wxBufferedDC)
+ DECLARE_NO_COPY_CLASS(wxBufferedDC)
+};
- wxBufferedDC( wxDC *dc, const wxBitmap &buffer );
- // Construct a wxBufferedDC with an internal buffer of 'area'
- // (where area is usually something like the size of the window
- // being buffered)
+// ----------------------------------------------------------------------------
+// Double buffered PaintDC.
+// ----------------------------------------------------------------------------
- wxBufferedDC( wxDC *dc, const wxSize &area );
+// Creates a double buffered wxPaintDC, optionally allowing the
+// user to specify their own buffer to use.
+class WXDLLEXPORT wxBufferedPaintDC : public wxBufferedDC
+{
+public:
+ // If no bitmap is supplied by the user, a temporary one will be created.
+ wxBufferedPaintDC(wxWindow *window, wxBitmap& buffer, int style = wxBUFFER_CLIENT_AREA)
+ : m_paintdc(window)
+ {
+ // If we're buffering the virtual window, scale the paint DC as well
+ if (style & wxBUFFER_VIRTUAL_AREA)
+ window->PrepareDC( m_paintdc );
+
+ if( buffer.IsOk() )
+ Init(&m_paintdc, buffer, style);
+ else
+ Init(&m_paintdc, GetBufferedSize(window, style), style);
+ }
+
+ // If no bitmap is supplied by the user, a temporary one will be created.
+ wxBufferedPaintDC(wxWindow *window, int style = wxBUFFER_CLIENT_AREA)
+ : m_paintdc(window)
+ {
+ // If we're using the virtual window, scale the paint DC as well
+ if (style & wxBUFFER_VIRTUAL_AREA)
+ window->PrepareDC( m_paintdc );
+
+ Init(&m_paintdc, GetBufferedSize(window, style), style);
+ }
// default copy ctor ok.
- // The usually desired action in the dtor is to blit the buffer.
+ virtual ~wxBufferedPaintDC()
+ {
+ // We must UnMask here, else by the time the base class
+ // does it, the PaintDC will have already been destroyed.
+ UnMask();
+ }
+
+protected:
+ // return the size needed by the buffer: this depends on whether we're
+ // buffering just the currently shown part or the total (scrolled) window
+ static wxSize GetBufferedSize(wxWindow *window, int style)
+ {
+ return style & wxBUFFER_VIRTUAL_AREA ? window->GetVirtualSize()
+ : window->GetClientSize();
+ }
+
+private:
+ wxPaintDC m_paintdc;
- ~wxBufferedDC();
+ DECLARE_ABSTRACT_CLASS(wxBufferedPaintDC)
+ DECLARE_NO_COPY_CLASS(wxBufferedPaintDC)
+};
- // These reimplement the actions of the ctors for
- // two stage creation, but are not used by the ctors
- // themselves to save a few cpu cycles.
- void Init( wxDC *dc, const wxBitmap &bitmap );
- void Init( wxDC *dc, const wxSize &area );
- // Blits the buffer to the dc, and detaches the dc from
- // the buffer. 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.
+//
+// wxAutoBufferedPaintDC is a wxPaintDC in toolkits which have double-
+// buffering by default. Otherwise it is a wxBufferedPaintDC. Thus,
+// you can only expect it work with a simple constructor that
+// accepts single wxWindow* argument.
+//
+#if wxALWAYS_NATIVE_DOUBLE_BUFFER
+ #define wxAutoBufferedPaintDCBase wxPaintDC
+#else
+ #define wxAutoBufferedPaintDCBase wxBufferedPaintDC
+#endif
- void UnMask();
- DECLARE_NO_COPY_CLASS(wxBufferedDC)
-};
+#ifdef __WXDEBUG__
+class wxAutoBufferedPaintDC : public wxAutoBufferedPaintDCBase
+{
+public:
-// ==============================================================
-// Double buffered PaintDC.
-// --------------------------------------------------------------
+ wxAutoBufferedPaintDC(wxWindow* win)
+ : wxAutoBufferedPaintDCBase(win)
+ {
+ TestWinStyle(win);
+ }
-// Creates a double buffered wxPaintDC, optionally allowing the
-// user to specify their own buffer to use.
+ virtual ~wxAutoBufferedPaintDC() { }
-class WXDLLEXPORT wxBufferedPaintDC : public wxBufferedDC
-{
private:
- wxPaintDC m_paintdc;
+ void TestWinStyle(wxWindow* win)
+ {
+ // Help the user to get the double-buffering working properly.
+ wxASSERT_MSG( win->GetBackgroundStyle() == wxBG_STYLE_CUSTOM,
+ wxT("In constructor, you need to call SetBackgroundStyle(wxBG_STYLE_CUSTOM), ")
+ wxT("and also, if needed, paint the background manually in the paint event handler."));
+ }
-public:
+ DECLARE_NO_COPY_CLASS(wxAutoBufferedPaintDC)
+};
- wxBufferedPaintDC( wxWindow *window, const wxBitmap &buffer = wxNullBitmap );
+#else // !__WXDEBUG__
- // default copy ctor ok.
+// In release builds, just use typedef
+typedef wxAutoBufferedPaintDCBase wxAutoBufferedPaintDC;
- ~wxBufferedPaintDC();
-};
+#endif
-#endif // _WX_DCBUFFER_H_
+// Check if the window is natively double buffered and will return a wxPaintDC
+// if it is, a wxBufferedPaintDC otherwise. It is the caller's responsibility
+// to delete the wxDC pointer when finished with it.
+inline wxDC* wxAutoBufferedPaintDCFactory(wxWindow* window)
+{
+ if ( window->IsDoubleBuffered() )
+ return new wxPaintDC(window);
+ else
+ return new wxBufferedPaintDC(window);
+}
-// vi:sts=4:sw=4:et
+#endif // _WX_DCBUFFER_H_
projects / wxWidgets.git / blobdiff