// Created: 16/03/02
// RCS-ID: $Id$
// Copyright: (c) Ron Lee
-// Licence: wxWidgets licence
+// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
#ifndef _WX_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
// ----------------------------------------------------------------------------
// Double buffering helper.
// ----------------------------------------------------------------------------
-class wxBufferedDC : public wxMemoryDC
+// Assumes the buffer bitmap covers the entire scrolled window,
+// and prepares the window DC accordingly
+#define wxBUFFER_VIRTUAL_AREA 0x01
+
+// Assumes the buffer bitmap only covers the client area;
+// does not prepare the window DC
+#define wxBUFFER_CLIENT_AREA 0x02
+
+// Set when not using specific buffer bitmap. Note that this
+// is private style and not returned by GetStyle.
+#define wxBUFFER_USES_SHARED_BUFFER 0x04
+
+class WXDLLEXPORT wxBufferedDC : public wxMemoryDC
{
public:
// Default ctor, must subsequently call Init for two stage construction.
- wxBufferedDC() : m_dc( 0 )
+ wxBufferedDC()
+ : m_dc(NULL),
+ m_buffer(NULL),
+ m_style(0)
{
}
// Construct a wxBufferedDC using a user supplied buffer.
- wxBufferedDC(wxDC *dc, const wxBitmap &buffer)
- : m_dc( dc ),
- m_buffer( buffer )
+ wxBufferedDC(wxDC *dc,
+ wxBitmap& buffer = wxNullBitmap,
+ int style = wxBUFFER_CLIENT_AREA)
+ : m_dc(NULL), m_buffer(NULL)
{
- UseBuffer();
+ 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)
- : m_dc( dc ),
- m_buffer( area.GetWidth(), area.GetHeight() )
+ wxBufferedDC(wxDC *dc, const wxSize& area, int style = wxBUFFER_CLIENT_AREA)
+ : m_dc(NULL), m_buffer(NULL)
{
- UseBuffer();
+ Init(dc, area, style);
}
- // default copy ctor ok.
-
// The usually desired action in the dtor is to blit the buffer.
virtual ~wxBufferedDC()
{
- if ( m_dc ) UnMask();
+ if ( m_dc )
+ UnMask();
}
- // 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 &buffer)
+ // These reimplement the actions of the ctors for two stage creation
+ void Init(wxDC *dc,
+ wxBitmap& buffer = wxNullBitmap,
+ int style = wxBUFFER_CLIENT_AREA)
{
- wxASSERT_MSG( m_dc == 0 && m_buffer == wxNullBitmap,
- _T("wxBufferedDC already initialised") );
- m_dc = dc;
- m_buffer = buffer;
+ InitCommon(dc, style);
+
+ m_buffer = &buffer;
+
UseBuffer();
}
- void Init(wxDC *dc, const wxSize &area)
+ void Init(wxDC *dc, const wxSize &area, int style = wxBUFFER_CLIENT_AREA)
{
- Init(dc, wxBitmap(area.GetWidth(), area.GetHeight()));
+ InitCommon(dc, style);
+
+ UseBuffer(area.x, area.y);
}
// Blits the buffer to the dc, and detaches the dc from the buffer (so it
// 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()
- {
- wxASSERT_MSG( m_dc != 0,
- _T("No underlying DC associated with wxBufferedDC (anymore)") );
+ void UnMask();
- m_dc->Blit( 0, 0,
- m_buffer.GetWidth(), m_buffer.GetHeight(), this,
- 0, 0 );
- m_dc = NULL;
- }
+ // Set and get the style
+ void SetStyle(int style) { m_style = style; }
+ int GetStyle() const { return m_style & ~wxBUFFER_USES_SHARED_BUFFER; }
private:
- // check that the bitmap is valid and use it
- void UseBuffer()
+ // common part of Init()s
+ void InitCommon(wxDC *dc, int style)
{
- wxASSERT_MSG( m_buffer.Ok(), _T("invalid bitmap in wxBufferedDC") );
+ wxASSERT_MSG( !m_dc, _T("wxBufferedDC already initialised") );
+
+ m_dc = dc;
+ m_style = style;
- SelectObject(m_buffer);
+ // inherit the same layout direction as the original DC
+ if (dc && dc->IsOk())
+ SetLayoutDirection(dc->GetLayoutDirection());
}
+ // check that the bitmap is valid and use it
+ void UseBuffer(wxCoord w = -1, wxCoord h = -1);
+
// the underlying DC to which we copy everything drawn on this one in
// UnMask()
//
// could probably be a reference.
wxDC *m_dc;
- // the buffer (selected in this DC)
- wxBitmap m_buffer;
+ // the buffer (selected in this DC), initially invalid
+ wxBitmap *m_buffer;
+
+ // the buffering style
+ int m_style;
+ DECLARE_DYNAMIC_CLASS(wxBufferedDC)
DECLARE_NO_COPY_CLASS(wxBufferedDC)
};
// Creates a double buffered wxPaintDC, optionally allowing the
// user to specify their own buffer to use.
-class wxBufferedPaintDC : public wxBufferedDC
+class WXDLLEXPORT wxBufferedPaintDC : public wxBufferedDC
{
public:
- // If no bitmap is supplied by the user, a temporary one wil; be created.
- wxBufferedPaintDC(wxWindow *window, const wxBitmap& buffer = wxNullBitmap)
+ // 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)
{
- window->PrepareDC( m_paintdc );
-
- if( buffer != wxNullBitmap )
- Init(&m_paintdc, buffer);
+ // 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, window->GetClientSize());
+ 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.
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;
+ DECLARE_ABSTRACT_CLASS(wxBufferedPaintDC)
DECLARE_NO_COPY_CLASS(wxBufferedPaintDC)
};
-#endif // _WX_DCBUFFER_H_
+
+//
+// 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
+
+
+#ifdef __WXDEBUG__
+
+class wxAutoBufferedPaintDC : public wxAutoBufferedPaintDCBase
+{
+public:
+
+ wxAutoBufferedPaintDC(wxWindow* win)
+ : wxAutoBufferedPaintDCBase(win)
+ {
+ TestWinStyle(win);
+ }
+
+ virtual ~wxAutoBufferedPaintDC() { }
+
+private:
+
+ 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."));
+ }
+
+ DECLARE_NO_COPY_CLASS(wxAutoBufferedPaintDC)
+};
+
+#else // !__WXDEBUG__
+
+// In release builds, just use typedef
+typedef wxAutoBufferedPaintDCBase wxAutoBufferedPaintDC;
+
+#endif
+
+
+// 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);
+}
+
+#endif // _WX_DCBUFFER_H_