Tricks of the Windows Gam…ming Gurus (2nd Edition)/Disc2.iso/msdn_vcb/samples/vc98/sdk/com/activexcontrol/webimage/dibcls.cpp

C/C++ Source or Header | 1997-10-09 | 4.5 KB | 202 lines

//=--------------------------------------------------------------------------=
// DibCls.Cpp
//=--------------------------------------------------------------------------=
// Copyright 1995 - 1997 Microsoft Corporation.  All Rights Reserved.
//
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
// PARTICULAR PURPOSE.
//=--------------------------------------------------------------------------=
//
// contains the CDibFile and CDibSection classes.
//
#include "IPServer.H"

#include "DibCls.H"

#define WIDTHBYTES(bits)    (((bits) + 31) / 32 * 4)

//=--------------------------------------------------------------------------=
// DIB Utitilty Classes
//=--------------------------------------------------------------------------=
// Not wholey generic but getting there...
//
// Notes:
//
CDibFile::CDibFile()
{
    m_headerSize = 0;
    m_bmi.p = 0;
}

CDibFile::~CDibFile()
{
    if( m_bmi.p )
        delete m_bmi.p;
}


DWORD CDibFile::CalcImageSize()
{
    DWORD & dw = m_bmi.p->bmiHeader.biSizeImage;
    if( dw == 0)
        dw = WIDTHBYTES((DWORD)m_bmi.p->bmiHeader.biWidth *
                m_bmi.p->bmiHeader.biBitCount) * m_bmi.p->bmiHeader.biHeight;

    return(dw);
}

HRESULT CDibFile::GetInfoHeader( IStream * strm )
{
    HRESULT hr = S_OK; m_bmi.bytes = new unsigned char[ m_headerSize ];

    if( !m_bmi.bytes )
        hr = E_OUTOFMEMORY;

    if( SUCCEEDED(hr) )
        hr = strm->Read(m_bmi.bytes,m_headerSize,0);

    if( SUCCEEDED(hr) )
        CalcImageSize();

    return(hr);
}

HRESULT CDibFile::GetFileHeader(IStream * strm)
{
    BITMAPFILEHEADER    bmfh;

    HRESULT    hr = strm->Read(&bmfh,sizeof(bmfh),0);

    if( SUCCEEDED(hr) && (bmfh.bfType != 0x4d42 ))
        hr = E_UNEXPECTED;

    if( SUCCEEDED(hr) )
        m_headerSize = bmfh.bfOffBits - sizeof(bmfh);

    return(hr);
}


CDibSection::CDibSection()
{
    m_bitsBase    = 0;
    m_current    = 0;
    m_memDC        = 0;
    m_handle    =
    m_oldBitmap = 0;
    m_w            =
    m_h            = 32;  // totally arbitrary
}

CDibSection::~CDibSection()
{
    if( m_memDC )
    {
        if( m_oldBitmap )
            ::SelectObject( m_memDC, m_oldBitmap );

        ::DeleteDC(m_memDC);
    }

    if( m_handle )
        ::DeleteObject(m_handle);

}


HRESULT CDibSection::Create(CDibFile& dibFile)
{
    HRESULT                hr        = S_OK;
    BITMAPINFOHEADER *    bmih    = dibFile;    // will convert itself

    m_handle = ::CreateDIBSection(
                    m_memDC,                // handle to device context
                    dibFile,                // pointer to structure containing bitmap size,
                                            //    format, and color data
                    DIB_RGB_COLORS,            // color data type indicator: RGB values or
                                            //    palette indices
                    (void **)&m_bitsBase,    // pointer to variable to receive a pointer
                                            //    to the bitmap's bit values
                    0,                        // optional handle to a file mapping object
                    0                        // offset to the bitmap bit values
                                            //    within the file mapping object
                    );

    if( !m_handle )
        hr = E_FAIL;

    if( SUCCEEDED(hr) )
    {
        m_oldBitmap = (HBITMAP) ::SelectObject( m_memDC, m_handle );

        if( !m_oldBitmap )
            hr = E_FAIL;
    }

    if( SUCCEEDED(hr) )
    {
        m_current = m_bitsBase;

        m_w = bmih->biWidth;
        m_h = bmih->biHeight;

        if( m_h < 0 )
            m_h *= -1;
    }

    return(hr);
}

HRESULT CDibSection::ReadFrom( IStream * strm, DWORD amount )
{
   DWORD    dwRead      = 0;
   HRESULT  hr;

   do
   {
      hr = strm->Read(m_current, m_imageSize, &dwRead);

      if (SUCCEEDED(hr) || hr == E_PENDING)
          m_current += dwRead;
   }
   while (!(hr == E_PENDING || hr == S_FALSE) && SUCCEEDED(hr));

   return (hr);
}


HRESULT CDibSection::Setup(HDC hdc)
{
    m_memDC = ::CreateCompatibleDC(hdc);

    return( m_memDC ? NOERROR : E_FAIL );
}


HRESULT    CDibSection::PaintTo(HDC hdc, int x, int y)
{
    BOOL b = BitBlt(
                 hdc,        // handle to destination device context
                 x,            // x-coordinate of destination rectangle's upper-left corner
                 y,            // x-coordinate of destination rectangle's upper-left corner
                 m_w,        // width of destination rectangle
                 m_h,        // height of destination rectangle
                 m_memDC,    // handle to source device context
                 0,            // x-coordinate of source rectangle's upper-left corner
                 0,            // y-coordinate of source rectangle's upper-left corner
                 SRCCOPY    // raster operation code
                );

    return( b ? NOERROR : E_FAIL );
}

HRESULT    CDibSection::GetSize(SIZEL &sz)
{
    sz.cx = m_w;
    sz.cy = m_h;

    return(S_OK);
}