src/Utils/MiscUI/BufferDC.cpp

   1 #include "stdafx.h"
   2 #include "BufferDC.h"
   3
   4 IMPLEMENT_DYNAMIC(CBufferDC, CPaintDC)
   5
   6 CBufferDC::CBufferDC(CWnd* pWnd) : CPaintDC(pWnd)
   7 {
   8         if (pWnd && CPaintDC::m_hDC)
   9         {
  10                 m_hOutputDC    = CPaintDC::m_hDC;
  11                 m_hAttributeDC = CPaintDC::m_hAttribDC;
  12
  13                 pWnd->GetClientRect(&m_ClientRect);
  14
  15                 m_hMemoryDC = ::CreateCompatibleDC(m_hOutputDC);
  16
  17                 m_hPaintBitmap =
  18                         ::CreateCompatibleBitmap(
  19                                         m_hOutputDC,
  20                                         m_ClientRect.right  - m_ClientRect.left,
  21                                         m_ClientRect.bottom - m_ClientRect.top);
  22
  23                 m_hOldBitmap = (HBITMAP)::SelectObject(m_hMemoryDC, m_hPaintBitmap);
  24
  25                 CPaintDC::m_hDC       = m_hMemoryDC;
  26                 CPaintDC::m_hAttribDC = m_hMemoryDC;
  27         }
  28         else
  29         {
  30                 ATLASSERT(false);
  31                 m_hAttributeDC = nullptr;
  32                 m_hOutputDC = nullptr;
  33                 m_hMemoryDC = nullptr;
  34                 m_hPaintBitmap = nullptr;
  35                 m_hOldBitmap = nullptr;
  36                 m_ClientRect.right = 0;
  37                 m_ClientRect.left = 0;
  38                 m_ClientRect.top = 0;
  39                 m_ClientRect.bottom = 0;
  40         }
  41
  42         m_bBoundsUpdated = FALSE;
  43 }
  44
  45 CBufferDC::~CBufferDC(void)
  46 {
  47         Flush();
  48
  49         ::SelectObject(m_hMemoryDC, m_hOldBitmap);
  50         ::DeleteObject(m_hPaintBitmap);
  51
  52         CPaintDC::m_hDC           = m_hOutputDC;
  53         CPaintDC::m_hAttribDC = m_hAttributeDC;
  54
  55         ::DeleteDC(m_hMemoryDC);
  56 }
  57
  58 void CBufferDC::Flush()
  59 {
  60         ::BitBlt(
  61                 m_hOutputDC,
  62                 m_ClientRect.left, m_ClientRect.top,
  63                 m_ClientRect.right  - m_ClientRect.left,
  64                 m_ClientRect.bottom - m_ClientRect.top,
  65                 m_hMemoryDC,
  66                 0, 0,
  67                 SRCCOPY);
  68 }
  69
  70 UINT CBufferDC::SetBoundsRect( LPCRECT lpRectBounds, UINT flags )
  71 {
  72         if (lpRectBounds)
  73         {
  74                 if (m_ClientRect.right  - m_ClientRect.left > lpRectBounds->right  - lpRectBounds->left ||
  75                         m_ClientRect.bottom - m_ClientRect.top  > lpRectBounds->bottom - lpRectBounds->top)
  76                 {
  77                         lpRectBounds = &m_ClientRect;
  78                 }
  79
  80                 HBITMAP bmp =
  81                         ::CreateCompatibleBitmap(
  82                                         m_hOutputDC,
  83                                         lpRectBounds->right - lpRectBounds->left,
  84                                         lpRectBounds->bottom - lpRectBounds->top);
  85
  86                 HDC tmpDC  = ::CreateCompatibleDC(m_hOutputDC);
  87
  88                 HBITMAP oldBmp = (HBITMAP)::SelectObject(tmpDC, bmp);
  89
  90                 ::BitBlt(
  91                         tmpDC,
  92                         m_ClientRect.left, m_ClientRect.top,
  93                         m_ClientRect.right  - m_ClientRect.left,
  94                         m_ClientRect.bottom - m_ClientRect.top,
  95                         m_hMemoryDC,
  96                         0, 0,
  97                         SRCCOPY);
  98
  99                 ::SelectObject(tmpDC, oldBmp);
 100                 ::DeleteDC(tmpDC);
 101
 102                 HBITMAP old = (HBITMAP)::SelectObject(m_hMemoryDC, bmp);
 103
 104                 if (old && old != m_hPaintBitmap)
 105                 {
 106                         ::DeleteObject(old);
 107                 }
 108
 109                 if (m_hPaintBitmap)
 110                 {
 111                         ::DeleteObject(m_hPaintBitmap);
 112                 }
 113
 114                 m_hPaintBitmap = bmp;
 115
 116                 m_ClientRect = *lpRectBounds;
 117                 m_bBoundsUpdated = TRUE;
 118         }
 119
 120         return CPaintDC::SetBoundsRect(lpRectBounds, flags);
 121 }
 122
 123 BOOL CBufferDC::RestoreDC( int nSavedDC )
 124 {
 125         BOOL ret = CPaintDC::RestoreDC(nSavedDC);
 126
 127         if (m_bBoundsUpdated)
 128         {
 129                 SelectObject(m_hPaintBitmap);
 130         }
 131
 132         return ret;
 133 }