dlls/x11drv/scroll.c

   1 /*
   2  * Scroll windows and DCs
   3  *
   4  * Copyright 1993  David W. Metcalfe
   5  * Copyright 1995, 1996 Alex Korobka
   6  * Copyright 2001 Alexandre Julliard
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #include "config.h"
  24
  25 #include <stdarg.h>
  26 #include <X11/Xlib.h>
  27
  28 #include "windef.h"
  29 #include "winbase.h"
  30 #include "wingdi.h"
  31 #include "winuser.h"
  32
  33 #include "x11drv.h"
  34 #include "win.h"
  35 #include "wine/debug.h"
  36
  37 WINE_DEFAULT_DEBUG_CHANNEL(scroll);
  38
  39
  40 /*************************************************************************
  41  *              ScrollDC   (X11DRV.@)
  42  */
  43 BOOL X11DRV_ScrollDC( HDC hdc, INT dx, INT dy, const RECT *lprcScroll,
  44                       const RECT *lprcClip, HRGN hrgnUpdate, LPRECT lprcUpdate )
  45
  46 {
  47     RECT rSrc, rClipped_src, rClip, rDst, offset;
  48     INT code = X11DRV_START_EXPOSURES;
  49
  50     if (hrgnUpdate || lprcUpdate)
  51         ExtEscape( hdc, X11DRV_ESCAPE, sizeof(code), (LPSTR)&code, 0, NULL );
  52
  53     /* compute device clipping region (in device coordinates) */
  54
  55     if (lprcScroll) rSrc = *lprcScroll;
  56     else GetClipBox( hdc, &rSrc );
  57     LPtoDP(hdc, (LPPOINT)&rSrc, 2);
  58
  59     if (lprcClip) rClip = *lprcClip;
  60     else GetClipBox( hdc, &rClip );
  61     LPtoDP(hdc, (LPPOINT)&rClip, 2);
  62
  63     IntersectRect( &rClipped_src, &rSrc, &rClip );
  64     TRACE("rSrc %s rClip %s clipped rSrc %s\n", wine_dbgstr_rect(&rSrc),
  65           wine_dbgstr_rect(&rClip), wine_dbgstr_rect(&rClipped_src));
  66
  67     rDst = rClipped_src;
  68     SetRect(&offset, 0, 0, dx, dy);
  69     LPtoDP(hdc, (LPPOINT)&offset, 2);
  70     OffsetRect( &rDst, offset.right - offset.left,  offset.bottom - offset.top );
  71     TRACE("rDst before clipping %s\n", wine_dbgstr_rect(&rDst));
  72     IntersectRect( &rDst, &rDst, &rClip );
  73     TRACE("rDst after clipping %s\n", wine_dbgstr_rect(&rDst));
  74
  75     if (!IsRectEmpty(&rDst))
  76     {
  77         /* copy bits */
  78         RECT rDst_lp = rDst, rSrc_lp = rDst;
  79
  80         OffsetRect( &rSrc_lp, offset.left - offset.right, offset.top - offset.bottom );
  81         DPtoLP(hdc, (LPPOINT)&rDst_lp, 2);
  82         DPtoLP(hdc, (LPPOINT)&rSrc_lp, 2);
  83
  84         if (!BitBlt( hdc, rDst_lp.left, rDst_lp.top,
  85                      rDst_lp.right - rDst_lp.left, rDst_lp.bottom - rDst_lp.top,
  86                      hdc, rSrc_lp.left, rSrc_lp.top, SRCCOPY))
  87             return FALSE;
  88     }
  89
  90     /* compute update areas.  This is the clipped source or'ed with the unclipped source translated minus the
  91      clipped src translated (rDst) all clipped to rClip */
  92
  93     if (hrgnUpdate || lprcUpdate)
  94     {
  95         HRGN hrgn = hrgnUpdate, hrgn2, hrgn3 = 0;
  96
  97         code = X11DRV_END_EXPOSURES;
  98         ExtEscape( hdc, X11DRV_ESCAPE, sizeof(code), (LPSTR)&code, sizeof(hrgn3), (LPSTR)&hrgn3 );
  99
 100         if (hrgn) SetRectRgn( hrgn, rClipped_src.left, rClipped_src.top, rClipped_src.right, rClipped_src.bottom );
 101         else hrgn = CreateRectRgn( rClipped_src.left, rClipped_src.top, rClipped_src.right, rClipped_src.bottom );
 102
 103         hrgn2 = CreateRectRgnIndirect( &rSrc );
 104         OffsetRgn(hrgn2, offset.right - offset.left,  offset.bottom - offset.top );
 105         CombineRgn(hrgn, hrgn, hrgn2, RGN_OR);
 106
 107         SetRectRgn( hrgn2, rDst.left, rDst.top, rDst.right, rDst.bottom );
 108         CombineRgn( hrgn, hrgn, hrgn2, RGN_DIFF );
 109
 110         SetRectRgn( hrgn2, rClip.left, rClip.top, rClip.right, rClip.bottom );
 111         CombineRgn( hrgn, hrgn, hrgn2, RGN_AND );
 112
 113         if (hrgn3)
 114         {
 115             CombineRgn( hrgn, hrgn, hrgn3, RGN_OR );
 116             DeleteObject( hrgn3 );
 117         }
 118
 119         if( lprcUpdate )
 120         {
 121             GetRgnBox( hrgn, lprcUpdate );
 122
 123             /* Put the lprcUpdate in logical coordinate */
 124             DPtoLP( hdc, (LPPOINT)lprcUpdate, 2 );
 125             TRACE("returning lprcUpdate %s\n", wine_dbgstr_rect(lprcUpdate));
 126         }
 127         if (!hrgnUpdate) DeleteObject( hrgn );
 128         DeleteObject( hrgn2 );
 129     }
 130     return TRUE;
 131 }