src/generic/dcbuffer.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        dcbuffer.cpp
   3 // Purpose:     wxBufferedDC class
   4 // Author:      Ron Lee <ron@debian.org>
   5 // Modified by:
   6 // Created:     16/03/02
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Ron Lee
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12
  13 #ifdef __GNUG__
  14     #pragma implementation "dcbuffer.h"
  15 #endif
  16
  17 #ifdef __BORLANDC__
  18     #pragma hdrstop
  19 #endif
  20
  21 #include "wx/dcbuffer.h"
  22
  23
  24 // ==============================================================
  25 //   Double buffering helper.
  26 // --------------------------------------------------------------
  27
  28 wxBufferedDC::wxBufferedDC( wxDC *dc, const wxBitmap &buffer )
  29     : m_dc( dc )
  30     , m_buffer( buffer )
  31 {
  32     SelectObject( m_buffer );
  33 }
  34
  35 wxBufferedDC::wxBufferedDC( wxDC *dc, const wxSize &area )
  36     : m_dc( dc )
  37     , m_buffer( area.GetWidth(), area.GetHeight() )
  38 {
  39     SelectObject( m_buffer );
  40 }
  41
  42 wxBufferedDC::~wxBufferedDC()
  43 {
  44     if( m_dc != 0 )
  45     {
  46         UnMask();
  47     }
  48 }
  49
  50 void wxBufferedDC::Init( wxDC *dc, const wxBitmap &buffer )
  51 {
  52     wxASSERT_MSG( m_dc == 0 && m_buffer == wxNullBitmap,
  53                   _T("wxBufferedDC already initialised") );
  54
  55     m_dc = dc;
  56     m_buffer = buffer;
  57     SelectObject( m_buffer );
  58 }
  59
  60 void wxBufferedDC::Init( wxDC *dc, const wxSize &area )
  61 {
  62     wxASSERT_MSG( m_dc == 0 && m_buffer == wxNullBitmap,
  63                   _T("wxBufferedDC already initialised") );
  64
  65     m_dc = dc;
  66     m_buffer = wxBitmap( area.GetWidth(), area.GetHeight() );
  67     SelectObject( m_buffer );
  68 }
  69
  70 void wxBufferedDC::UnMask()
  71 {
  72     wxASSERT_MSG( m_dc != 0, _T("No low level DC associated with buffer (anymore)") );
  73
  74     m_dc->Blit( 0, 0, m_buffer.GetWidth(), m_buffer.GetHeight(), this, 0, 0 );
  75     m_dc = 0;
  76 }
  77
  78
  79 // ==============================================================
  80 //   Double buffered PaintDC.
  81 // --------------------------------------------------------------
  82
  83 wxBufferedPaintDC::wxBufferedPaintDC( wxWindow *window, const wxBitmap &buffer )
  84     : m_paintdc( window )
  85 {
  86     window->PrepareDC( m_paintdc );
  87
  88     if( buffer != wxNullBitmap )
  89         Init( &m_paintdc, buffer );
  90     else
  91         Init( &m_paintdc, window->GetClientSize() );
  92 }
  93
  94 wxBufferedPaintDC::~wxBufferedPaintDC()
  95 {
  96         // We must UnMask here, else by the time the base class
  97         // does it, the PaintDC will have already been destroyed.
  98
  99     UnMask();
 100 }
 101
 102
 103 // vi:sts=4:sw=4:et