◄CDC►                                         ◄Up► ◄Contents► ◄Index► ◄Back►
──Microsoft Foundation Classes──────────────────────────────────────────────
 
  BOOL BitBlt( int x, int y, int nWidth, int nHeight, CDC* pSrcDC,
               int xSrc, int ySrc, DWORD dwRop );
 
  Parameter   Description
 
  <x>         Specifies the logical x-coordinate of the upper-left corner
              of the destination rectangle.
 
  <y>         Specifies the logical y-coordinate of the upper-left corner
              of the destination rectangle.
 
  <nWidth>    Specifies the width (in logical units) of the destination
              rectangle and source bitmap.
 
  <nHeight>   Specifies the height (in logical units) of the destination
              rectangle and source bitmap.
 
  <pSrcDC>    Pointer to a CDC object that identifies the device context
              from which the bitmap will be copied. It must be NULL if
              <dwRop> specifies a raster operation that does not include a
              source.
 
  <xSrc>      Specifies the logical x-coordinate of the upper-left corner
              of the source bitmap.
 
  <ySrc>      Specifies the logical y-coordinate of the upper-left corner
              of the source bitmap.
 
  <dwRop>     Specifies the raster operation to be performed.
              Raster-operation codes define how the graphics device
              interface (GDI) combines colors in output operations that
              involve a current brush, a possible source bitmap, and a
              destination bitmap. The following lists raster-operation
              codes for <dwRop>:
 
              Code          Description
 
              BLACKNESS     Turns all output black.
 
              DSTINVERT     Inverts the destination bitmap.
 
              MERGECOPY     Combines the pattern and the source bitmap
                            using the Boolean AND operator.
 
              MERGEPAINT    Combines the inverted source bitmap with the
                            destination bitmap using the Boolean OR
                            operator.
 
              NOTSRCCOPY    Copies the inverted source bitmap to the
                            destination.
 
              NOTSRCERASE   Inverts the result of combining the
                            destination and source bitmaps using the
                            Boolean OR operator.
 
              PATCOPY       Copies the pattern to the destination bitmap.
 
              PATINVERT     Combines the destination bitmap with the
                            pattern using the Boolean XOR operator.
 
              PATPAINT      Combines the inverted source bitmap with the
                            pattern using the Boolean OR operator.
                            Combines the result of this operation with the
                            destination bitmap using the Boolean OR
                            operator.
 
              SRCAND        Combines pixels of the destination and source
                            bitmaps using the Boolean AND operator.
 
              SRCCOPY       Copies the source bitmap to the destination
                            bitmap.
 
              SRCERASE      Inverts the desination bitmap and combines the
                            result with the source bitmap using the
                            Boolean AND operator.
 
              SRCINVERT     Combines pixels of the destination and source
                            bitmaps using the Boolean XOR operator.
 
              SRCPAINT      Combines pixels of the destination and source
                            bitmaps using the Boolean OR operator.
 
              WHITENESS     Turns all output white.
 
              For a complete list of raster-operation codes, see the
              Windows Software Development Kit documentation.
 
  Remarks
 
  Copies a bitmap from the source device context to this current device
  context.
 
  The application can align the windows or client areas on byte boundaries
  to ensure that the BitBlt operations occur on byte-aligned rectangles.
  (Set the CS_BYTEALIGNWINDOW or CS_BYTEALIGNCLIENT flags when you
  register the window classes.)
 
  BitBlt operations on byte-aligned rectangles are considerably faster
  than BitBlt operations on rectangles that are not byte aligned. If you
  want to specify class styles such as byte-alignment or your own device
  context, you will have to register a window class rather than relying on
  the Foundation classes to do it for you. Use the Foundation global
  function ◄AfxRegisterWndClass►.
 
  GDI transforms <nWidth> and <nHeight>, once by using the destination
  display context, and once by using the source display context. If the
  resulting extents do not match, GDI uses the Windows StretchBlt function
  to compress or stretch the source bitmap as necessary.
 
  If destination, source, and pattern bitmaps do not have the same color
  format, the BitBlt function converts the source and pattern bitmaps to
  match the destination. The foreground and background colors of the
  destination are used in the conversion.
 
  Note that not all device contexts support BitBlt. To check whether a
  given device context does support BitBlt, use GetDeviceCaps.
 
  Return Value
 
  TRUE if the bitmap is drawn; otherwise FALSE.
 
  See Also
 
  ◄CDC::GetDeviceCaps►, ◄CDC::PatBlt►, ◄CDC::SetTextColor►,
  ◄CDC::StretchBlt►, ◄::StretchDIBits►, ◄::BitBlt►
 
 
                                     -♦-