How To Fit Text in a Rectangle

BOOL GetTextBlackExtentPoint(
  HDC hdc,           // handle to DC
  LPCTSTR lpString,  // text string
  int cbString,      // number of characters in string
  LPSIZE lpSize      // string size
)
{
    SIZE sizeTx;
    ABC lead;
    ABC trail;
    TCHAR ch = lpString[lstrlen(lpString)-1];

    if (NULL == lpSize)
        return false;

    if (!GetTextExtentPoint32(hdc, lpString, cbString, &sizeTx))
        return false;

    if (!GetCharABCWidths(hdc, lpString[0], lpString[0], &lead))
        return false;
    if (!GetCharABCWidths(hdc, ch, ch, &trail))
        return false;
    sizeTx.cx = sizeTx.cx - lead.abcA -trail.abcC;
    *lpSize = sizeTx;
    return true;
}


BOOL SnugTextOut( HDC hDC, RECT &rc, LPTSTR szString )
{
    int     i, nStringLength;
    BOOL    bResult;
    int     *pDx;
    int     nX = rc.left;
    int     nY = rc.top;
    int     Width = 0;

    // How long is the string - you need this later in this code.
    nStringLength = lstrlen( szString );

    // Allocate enough memory for the intercharacter spacing array.
    pDx = (int *)new int[ sizeof(int) * nStringLength ];

    // Initialize the array with the standard values.
    for(i=0; i < nStringLength; i++)
    {
        ABC     abc;
        if( ! GetCharABCWidths( hDC, szString[i], szString[i], &abc ) )
        {
            delete [] pDx;
            return FALSE;
        }
        pDx[i] = abc.abcA + abc.abcB + abc.abcC;
        
        // You need the width.
        Width += pDx[i];
        
        // Also, account for the Black extent of the string.
        if (i == 0)
        {
            // Adjustment before the first character for underhang
            nX -= abc.abcA;
            Width -= abc.abcA;
        }
        if (i == nStringLength-1)
        {
            // Adjustment for overhang
            Width -= abc.abcC;
        }

    }

    int deltaCX = rc.right-rc.left - Width;
    int deltaCh = deltaCX / nStringLength;
    int remainder = deltaCX % nStringLength;
    int error = 0;

    // Distribute the adjustment through the intercharacter spacing.
    // For a more typographically correct approach, distribute the 
    // adjustment in the "white space."
    for(i=0; i < nStringLength; i++)
    {
        pDx[i] += deltaCh;
        error += remainder;
        if (abs(error) >= nStringLength)    // adjustment?
        {
            int adjustment = abs(error)/error;
            pDx[i] += adjustment;
            error -= nStringLength*adjustment;
        }

    }

    // ExtTextOut() draws our text with our ICS array.
    bResult = ExtTextOut( hDC, nX, nY, 0, &rc, szString, nStringLength, pDx );

    // Clean up.
    delete [] pDx;
    return bResult;
}

double ScaleFactor = 1.0;

BOOL OnPaint(HWND hWnd)
{
    PAINTSTRUCT     ps;
    HDC             hdc;
    LOGFONT         lf;
    HFONT           hFont, hScaledFont, hOldFont;
    SIZE            sizeText;
    TCHAR           Buffer[] = TEXT("for this is sample text of");
    RECT            rcText;

    hdc = BeginPaint(hWnd, &ps);

    // Get the unscaled metrics.
    ZeroMemory(&lf, sizeof(lf));
    lf.lfHeight = -MulDiv( 14, GetDeviceCaps(hdc, LOGPIXELSY), 72 );
    lf.lfCharSet = ANSI_CHARSET;
    lf.lfItalic = true;
    lstrcpy(lf.lfFaceName, TEXT("Times New Roman"));
    hFont = CreateFontIndirect(&lf);
    hOldFont = (HFONT)SelectObject(hdc, hFont);

    GetTextBlackExtentPoint(hdc, Buffer, lstrlen(Buffer), &sizeText);
    SelectObject(hdc, hOldFont);


    // Draw the scaled text.
    lf.lfHeight = -MulDiv( 14*ScaleFactor*100, GetDeviceCaps(hdc, LOGPIXELSY), 7200 );
    lf.lfCharSet = ANSI_CHARSET;
    lf.lfItalic = true;
    lstrcpy(lf.lfFaceName, TEXT("Times New Roman"));
    hScaledFont = CreateFontIndirect(&lf);

    SelectObject(hdc, hScaledFont);

    rcText.left = 100;
    rcText.top = 100;
    rcText.right = rcText.left + sizeText.cx*ScaleFactor;
    rcText.bottom = rcText.top + sizeText.cy*ScaleFactor;

    SnugTextOut(hdc, rcText, Buffer);

    SelectObject(hdc, GetStockObject(NULL_BRUSH));

    // Rectangles are right-bottom exclusive.
    rcText.right++;
    rcText.bottom++;
    Rectangle(hdc, rcText.left, rcText.top, rcText.right, rcText.bottom);

    // Clean up.
    SelectObject(hdc, hOldFont);
    DeleteObject(hFont);
    DeleteObject(hScaledFont);

    EndPaint(hWnd, &ps);
    return true;
}