// Double buffering helper.
// ----------------------------------------------------------------------------
+// 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
+
class wxBufferedDC : public wxMemoryDC
{
public:
// Default ctor, must subsequently call Init for two stage construction.
- wxBufferedDC() : m_dc( 0 )
+ wxBufferedDC() : m_dc( 0 ), m_style(0)
{
}
// Construct a wxBufferedDC using a user supplied buffer.
- wxBufferedDC(wxDC *dc, const wxBitmap &buffer)
+ wxBufferedDC(wxDC *dc,
+ const wxBitmap &buffer = wxNullBitmap,
+ int style = wxBUFFER_CLIENT_AREA)
: m_dc( dc ),
- m_buffer( buffer )
+ m_buffer( buffer ),
+ m_style(style)
{
UseBuffer();
}
// 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)
+ wxBufferedDC(wxDC *dc, const wxSize &area, int style = wxBUFFER_CLIENT_AREA)
: m_dc( dc ),
- m_buffer( area.GetWidth(), area.GetHeight() )
+ m_buffer( area.GetWidth(), area.GetHeight() ),
+ m_style(style)
+
{
UseBuffer();
}
// 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)
+ void Init(wxDC *dc,
+ const 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;
+ m_style = style;
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()));
+ Init(dc, wxBitmap(area.GetWidth(), area.GetHeight()), style);
}
// Blits the buffer to the dc, and detaches the dc from the buffer (so it
wxASSERT_MSG( m_dc != 0,
_T("No underlying DC associated with wxBufferedDC (anymore)") );
- wxCoord x, y;
- GetDeviceOrigin(& x, & y);
+ 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,
m_dc = NULL;
}
+ // Set and get the style
+ void SetStyle(int style) { m_style = style; }
+ int GetStyle() const { return m_style; }
+
private:
// check that the bitmap is valid and use it
void UseBuffer()
{
- wxASSERT_MSG( m_buffer.Ok(), _T("invalid bitmap in wxBufferedDC") );
+ if (!m_buffer.Ok())
+ {
+ wxCoord w, h;
+ m_dc->GetSize(&w, &h);
+ m_buffer = wxBitmap(w, h);
+ }
SelectObject(m_buffer);
}
// the buffer (selected in this DC)
wxBitmap m_buffer;
+ // the buffering style
+ int m_style;
+
DECLARE_NO_COPY_CLASS(wxBufferedDC)
};
class 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, const 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 != wxNullBitmap )
- Init(&m_paintdc, buffer);
+ Init(&m_paintdc, buffer, style);
else
- Init(&m_paintdc, window->GetClientSize());
+ Init(&m_paintdc, window->GetClientSize(), 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, window->GetClientSize(), style);
}
// default copy ctor ok.