font.c

winNT技术操作系统,国外开放的原代码和LIUX一样

static void TEXT_DrawUnderscore (HDC hdc, int x, int y, const WCHAR *str, int offset, const RECT *rect)
{
    int prefix_x;
    int prefix_end;
    SIZE size;
    HPEN hpen;
    HPEN oldPen;

    GetTextExtentPointW (hdc, str, offset, &size);
    prefix_x = x + size.cx;
    GetTextExtentPointW (hdc, str, offset+1, &size);
    prefix_end = x + size.cx - 1;
    /* The above method may eventually be slightly wrong due to kerning etc. */

    /* Check for clipping */
    if (rect)
    {
        if (prefix_x > rect->right || prefix_end < rect->left ||
            y < rect->top || y > rect->bottom)
            return; /* Completely outside */
        /* Partially outside */
        if (prefix_x   < rect->left ) prefix_x   = rect->left;
        if (prefix_end > rect->right) prefix_end = rect->right;
    }
    
    hpen = CreatePen (PS_SOLID, 1, GetTextColor (hdc));
    oldPen = SelectObject (hdc, hpen);
    MoveToEx (hdc, prefix_x, y, NULL);
    LineTo (hdc, prefix_end, y);
    SelectObject (hdc, oldPen);
    DeleteObject (hpen);
}

/***********************************************************************
 *           DrawTextExW    (USER32.@)
 *
 * The documentation on the extra space required for DT_MODIFYSTRING at MSDN
 * is not quite complete, especially with regard to \0.  We will assume that
 * the returned string could have a length of up to i_count+3 and also have
 * a trailing \0 (which would be 4 more than a not-null-terminated string but
 * 3 more than a null-terminated string).  If this is not so then increase
 * the allowance in DrawTextExA.
 */
#define MAX_BUFFER 1024
/* WINE synced 22-May-2006 */
/*
 * @implemented
 */
int STDCALL
DrawTextExW( HDC hdc, LPWSTR str, INT i_count,
             LPRECT rect, UINT flags, LPDRAWTEXTPARAMS dtp )
{
    SIZE size;
    const WCHAR *strPtr;
    WCHAR *retstr, *p_retstr;
    size_t size_retstr;
    WCHAR line[MAX_BUFFER];
    int len, lh, count=i_count;
    TEXTMETRICW tm;
    int lmargin = 0, rmargin = 0;
    int x = rect->left, y = rect->top;
    int width = rect->right - rect->left;
    int max_width = 0;
    int last_line;
    int tabwidth /* to keep gcc happy */ = 0;
    int prefix_offset;
    ellipsis_data ellip;

#if 0
    TRACE("%s, %d, [%s] %08x\n", debugstr_wn (str, count), count,
        wine_dbgstr_rect(rect), flags);

   if (dtp) TRACE("Params: iTabLength=%d, iLeftMargin=%d, iRightMargin=%d\n",
          dtp->iTabLength, dtp->iLeftMargin, dtp->iRightMargin);
#endif

    if (!str || count == 0) return 0;
    if (count == -1)
    {
        count = strlenW(str);
        if (count == 0)
        {
            if( flags & DT_CALCRECT)
            {
                rect->right = rect->left;
                rect->bottom = rect->top;
            }
            return 0;
        }
    }
    strPtr = str;

    if (flags & DT_SINGLELINE)
        flags &= ~DT_WORDBREAK;

    GetTextMetricsW(hdc, &tm);
    if (flags & DT_EXTERNALLEADING)
        lh = tm.tmHeight + tm.tmExternalLeading;
    else
        lh = tm.tmHeight;

    if (dtp)
    {
        lmargin = dtp->iLeftMargin * tm.tmAveCharWidth;
        rmargin = dtp->iRightMargin * tm.tmAveCharWidth;
        if (!(flags & (DT_CENTER | DT_RIGHT)))
            x += lmargin;
        dtp->uiLengthDrawn = 0;     /* This param RECEIVES number of chars processed */
    }

    if (flags & DT_EXPANDTABS)
    {
        int tabstop = ((flags & DT_TABSTOP) && dtp) ? dtp->iTabLength : 8;
        tabwidth = tm.tmAveCharWidth * tabstop;
    }

    if (flags & DT_CALCRECT) flags |= DT_NOCLIP;

    if (flags & DT_MODIFYSTRING)
    {
        size_retstr = (count + 4) * sizeof (WCHAR);
        retstr = HeapAlloc(GetProcessHeap(), 0, size_retstr);
        if (!retstr) return 0;
        memcpy (retstr, str, size_retstr);
    }
    else
    {
        size_retstr = 0;
        retstr = NULL;
    }
    p_retstr = retstr;

    do
    {
        len = sizeof(line)/sizeof(line[0]);
        last_line = !(flags & DT_NOCLIP) && y + ((flags & DT_EDITCONTROL) ? 2*lh-1 : lh) > rect->bottom;
        strPtr = TEXT_NextLineW(hdc, strPtr, &count, line, &len, width, flags, &size, last_line, &p_retstr, tabwidth, &prefix_offset, &ellip);

    if (flags & DT_CENTER)
        x = (rect->left + rect->right - size.cx) / 2;
    else if (flags & DT_RIGHT) x = rect->right - size.cx;

    if (flags & DT_SINGLELINE)
    {
        if (flags & DT_VCENTER) y = rect->top +
            (rect->bottom - rect->top) / 2 - size.cy / 2;
        else if (flags & DT_BOTTOM) y = rect->bottom - size.cy;
    }

    if (!(flags & DT_CALCRECT))
    {
            const WCHAR *str = line;
            int xseg = x;
            while (len)
            {
                int len_seg;
                SIZE size;
                if ((flags & DT_EXPANDTABS))
                {
                    const WCHAR *p;
                    p = str; while (p < str+len && *p != TAB) p++;
                    len_seg = p - str;
                    if (len_seg != len && !GetTextExtentPointW(hdc, str, len_seg, &size))
                        return 0;
                }
                else
                    len_seg = len;

                if (!ExtTextOutW( hdc, xseg, y,
                                 ((flags & DT_NOCLIP) ? 0 : ETO_CLIPPED) |
                                 ((flags & DT_RTLREADING) ? ETO_RTLREADING : 0),
                                 rect, str, len_seg, NULL ))  return 0;
                if (prefix_offset != -1 && prefix_offset < len_seg)
                {
                    TEXT_DrawUnderscore (hdc, xseg, y + tm.tmAscent + 1, str, prefix_offset, (flags & DT_NOCLIP) ? NULL : rect);
                }
                len -= len_seg;
                str += len_seg;
                if (len)
                {
                    assert ((flags & DT_EXPANDTABS) && *str == TAB);
                    len--; str++;
                    xseg += ((size.cx/tabwidth)+1)*tabwidth;
                    if (prefix_offset != -1)
                    {
                        if (prefix_offset < len_seg)
                        {
                            /* We have just drawn an underscore; we ought to
                             * figure out where the next one is.  I am going
                             * to leave it for now until I have a better model
                             * for the line, which will make reprefixing easier.
                             * This is where ellip would be used.
                             */
                            prefix_offset = -1;
                        }
                        else
                            prefix_offset -= len_seg;
                    }
                }
            }
    }
    else if (size.cx > max_width)
        max_width = size.cx;

    y += lh;
        if (dtp)
            dtp->uiLengthDrawn += len;
    }
    while (strPtr && !last_line);

    if (flags & DT_CALCRECT)
    {
        rect->right = rect->left + max_width;
        rect->bottom = y;
        if (dtp)
            rect->right += lmargin + rmargin;
    }
    if (retstr)
    {
        memcpy (str, retstr, size_retstr);
        HeapFree (GetProcessHeap(), 0, retstr);
    }
    return y - rect->top;
}

/***********************************************************************
 *           DrawTextExA    (USER32.@)
 *
 * If DT_MODIFYSTRING is specified then there must be room for up to
 * 4 extra characters.  We take great care about just how much modified
 * string we return.
 *
 * @implemented
 */
/* WINE synced 22-May-2006 */
int STDCALL
DrawTextExA( HDC hdc, LPSTR str, INT count,
             LPRECT rect, UINT flags, LPDRAWTEXTPARAMS dtp )
{
   WCHAR *wstr;
   WCHAR *p;
   INT ret = 0;
   int i;
   DWORD wcount;
   DWORD wmax;
   DWORD amax;

   if (!count) return 0;
   if( !str || ((count == -1) && !(count = strlen(str))))
   {
        if( flags & DT_CALCRECT)
        {
            rect->right = rect->left;
            rect->bottom = rect->top;
        }
        return 0;
   }
   wcount = MultiByteToWideChar( CP_ACP, 0, str, count, NULL, 0 );
   wmax = wcount;
   amax = count;
   if (flags & DT_MODIFYSTRING)
   {
        wmax += 4;
        amax += 4;
   }
   wstr = HeapAlloc(GetProcessHeap(), 0, wmax * sizeof(WCHAR));
   if (wstr)
   {
       MultiByteToWideChar( CP_ACP, 0, str, count, wstr, wcount );
       if (flags & DT_MODIFYSTRING)
           for (i=4, p=wstr+wcount; i--; p++) *p=0xFFFE;
           /* Initialise the extra characters so that we can see which ones
            * change.  U+FFFE is guaranteed to be not a unicode character and
            * so will not be generated by DrawTextEx itself.
            */
       ret = DrawTextExW( hdc, wstr, wcount, rect, flags, dtp );
       if (flags & DT_MODIFYSTRING)
       {
            /* Unfortunately the returned string may contain multiple \0s
             * and so we need to measure it ourselves.
             */
            for (i=4, p=wstr+wcount; i-- && *p != 0xFFFE; p++) wcount++;
            WideCharToMultiByte( CP_ACP, 0, wstr, wcount, str, amax, NULL, NULL );
       }
       HeapFree(GetProcessHeap(), 0, wstr);
   }
   return ret;
}

/***********************************************************************
 *           DrawTextW    (USER32.@)
 *
 * @implemented
 */
int STDCALL
DrawTextW( HDC hdc, LPCWSTR str, INT count, LPRECT rect, UINT flags )
{
    DRAWTEXTPARAMS dtp;

    memset (&dtp, 0, sizeof(dtp));
    if (flags & DT_TABSTOP)
    {
        dtp.iTabLength = (flags >> 8) && 0xff;
        flags &= 0xffff00ff;
    }
    return DrawTextExW(hdc, (LPWSTR)str, count, rect, flags, &dtp);
}

/***********************************************************************
 *           DrawTextA    (USER32.@)
 *
 * @implemented
 */
int STDCALL
DrawTextA( HDC hdc, LPCSTR str, INT count, LPRECT rect, UINT flags )
{
    DRAWTEXTPARAMS dtp;

    memset (&dtp, 0, sizeof(dtp));
    if (flags & DT_TABSTOP)
    {
        dtp.iTabLength = (flags >> 8) && 0xff;
        flags &= 0xffff00ff;
    }
    return DrawTextExA( hdc, (LPSTR)str, count, rect, flags, &dtp );
}