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 "wine/debug.h"
  35
  36 WINE_DEFAULT_DEBUG_CHANNEL(scroll);
  37
  38 static void dump_region( char *p, HRGN hrgn)
  39 {
  40     DWORD i, size;
  41     RGNDATA *data = NULL;
  42     RECT *rect;
  43
  44     if (!hrgn) {
  45         TRACE( "%s null region\n", p );
  46         return;
  47     }
  48     if (!(size = GetRegionData( hrgn, 0, NULL ))) {
  49         return;
  50     }
  51     if (!(data = HeapAlloc( GetProcessHeap(), 0, size ))) return;
  52     GetRegionData( hrgn, size, data );
  53     TRACE("%s %ld rects:", p, data->rdh.nCount );
  54     for (i = 0, rect = (RECT *)data->Buffer; i<20 && i < data->rdh.nCount; i++, rect++)
  55         TRACE( " %s", wine_dbgstr_rect( rect));
  56     TRACE("\n");
  57     HeapFree( GetProcessHeap(), 0, data );
  58 }
  59
  60 /*************************************************************************
  61  *              ScrollDC   (X11DRV.@)
  62  */
  63 BOOL X11DRV_ScrollDC( HDC hdc, INT dx, INT dy, const RECT *lprcScroll,
  64                       const RECT *lprcClip, HRGN hrgnUpdate, LPRECT lprcUpdate )
  65 {
  66     RECT rcSrc, rcClip, offset;
  67     INT dxdev, dydev, res;
  68     HRGN DstRgn, clipRgn, visrgn;
  69     INT code = X11DRV_START_EXPOSURES;
  70
  71     TRACE("dx,dy %d,%d lprcScroll %p lprcClip %p hrgnUpdate %p lprcUpdate %p\n",
  72             dx, dy, lprcScroll, lprcClip, hrgnUpdate, lprcUpdate);
  73     /* enable X-exposure events */
  74     if (hrgnUpdate || lprcUpdate)
  75         ExtEscape( hdc, X11DRV_ESCAPE, sizeof(code), (LPSTR)&code, 0, NULL );
  76     /* get the visible region */
  77     visrgn=CreateRectRgn( 0, 0, 0, 0);
  78     GetRandomRgn( hdc, visrgn, SYSRGN);
  79     if( !(GetVersion() & 0x80000000)) {
  80         /* Window NT/2k/XP */
  81         POINT org;
  82         GetDCOrgEx(hdc, &org);
  83         OffsetRgn( visrgn, -org.x, -org.y);
  84     }
  85     /* intersect with the clipping Region if the DC has one */
  86     clipRgn = CreateRectRgn( 0, 0, 0, 0);
  87     if (GetClipRgn( hdc, clipRgn) != 1) {
  88         DeleteObject(clipRgn);
  89         clipRgn=NULL;
  90     } else
  91         CombineRgn( visrgn, visrgn, clipRgn, RGN_AND);
  92     /* only those pixels in the scroll rectangle that remain in the clipping
  93      * rect are scrolled. So first combine Scroll and Clipping rectangles,
  94      * if available */
  95     if( lprcScroll)
  96         if( lprcClip)
  97             IntersectRect( &rcClip, lprcClip, lprcScroll);
  98         else
  99             rcClip = *lprcScroll;
 100     else
 101         if( lprcClip)
 102             rcClip = *lprcClip;
 103         else
 104             GetClipBox( hdc, &rcClip);
 105     /* Then clip again to get the source rectangle that will remain in the
 106      * clipping rect */
 107     rcSrc = rcClip;
 108     OffsetRect( &rcSrc, -dx, -dy);
 109     IntersectRect( &rcSrc, &rcSrc, &rcClip);
 110     /* now convert to device coordinates */
 111     LPtoDP(hdc, (LPPOINT)&rcSrc, 2);
 112     /* also dx and dy */
 113     SetRect(&offset, 0, 0, dx, dy);
 114     LPtoDP(hdc, (LPPOINT)&offset, 2);
 115     dxdev = offset.right - offset.left;
 116     dydev= offset.bottom - offset.top;
 117     /* now intersect with the visible region to get the pixels that will
 118      * actually scroll */
 119     DstRgn = CreateRectRgnIndirect( &rcSrc);
 120     res = CombineRgn( DstRgn, DstRgn, visrgn, RGN_AND);
 121     /* and translate, giving the destination region */
 122     OffsetRgn( DstRgn, dxdev, dydev);
 123     if( TRACE_ON( scroll)) dump_region( "Destination scroll region: ", DstRgn);
 124     /* if there are any, do it */
 125     if( res > NULLREGION) {
 126         RECT rect ;
 127         /* clip to the destination region, so we can BitBlt with a simple
 128          * bounding rectangle */
 129         if( clipRgn)
 130             ExtSelectClipRgn( hdc, DstRgn, RGN_AND);
 131         else
 132             SelectClipRgn( hdc, DstRgn);
 133         GetRgnBox( DstRgn, &rect);
 134         DPtoLP(hdc, (LPPOINT)&rect, 2);
 135         BitBlt( hdc, rect.left, rect.top,
 136                     rect.right - rect.left, rect.bottom -rect.top,
 137                     hdc, rect.left - dx, rect.top - dy, SRCCOPY);
 138     }
 139     /* compute the update areas.  This is the combined clip rectangle
 140      * minus the scrolled region, and intersected with the visible
 141      * region. */
 142     if (hrgnUpdate || lprcUpdate)
 143     {
 144         HRGN hrgn = hrgnUpdate;
 145         HRGN ExpRgn = 0;
 146
 147         /* collect all the exposures */
 148         code = X11DRV_END_EXPOSURES;
 149         ExtEscape( hdc, X11DRV_ESCAPE, sizeof(code), (LPSTR)&code,
 150                 sizeof(ExpRgn), (LPSTR)&ExpRgn );
 151         /* Covert the combined clip rectangle to device coordinates */
 152         LPtoDP(hdc, (LPPOINT)&rcClip, 2);
 153         if( hrgn )
 154             SetRectRgn( hrgn, rcClip.left, rcClip.top, rcClip.right,
 155                     rcClip.bottom);
 156         else
 157             hrgn = CreateRectRgnIndirect( &rcClip);
 158         CombineRgn( hrgn, hrgn, visrgn, RGN_AND);
 159         CombineRgn( hrgn, hrgn, DstRgn, RGN_DIFF);
 160         /* add the exposures to this */
 161         if( ExpRgn) {
 162             if( TRACE_ON( scroll)) dump_region( "Expose region: ", ExpRgn);
 163             CombineRgn( hrgn, hrgn, ExpRgn, RGN_OR);
 164             DeleteObject( ExpRgn);
 165         }
 166         if( TRACE_ON( scroll)) dump_region( "Update region: ", hrgn);
 167         if( lprcUpdate) {
 168             GetRgnBox( hrgn, lprcUpdate );
 169             /* Put the lprcUpdate in logical coordinates */
 170             DPtoLP( hdc, (LPPOINT)lprcUpdate, 2 );
 171             TRACE("returning lprcUpdate %s\n", wine_dbgstr_rect(lprcUpdate));
 172         }
 173         if( !hrgnUpdate)
 174             DeleteObject( hrgn);
 175     }
 176     SelectClipRgn( hdc, clipRgn);
 177     DeleteObject( visrgn);
 178     DeleteObject( DstRgn);
 179     if( clipRgn) DeleteObject( clipRgn);
 180     return TRUE;
 181 }