dlls/winex11.drv/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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, 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( const 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 %d 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 CDECL 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 rcScroll %s rcClip %s hrgnUpdate %p lprcUpdate %p\n",
  72             dx, dy, wine_dbgstr_rect(lprcScroll), wine_dbgstr_rect(lprcClip),
  73             hrgnUpdate, lprcUpdate);
  74     /* enable X-exposure events */
  75     if (hrgnUpdate || lprcUpdate)
  76         ExtEscape( hdc, X11DRV_ESCAPE, sizeof(code), (LPSTR)&code, 0, NULL );
  77     /* get the visible region */
  78     visrgn=CreateRectRgn( 0, 0, 0, 0);
  79     GetRandomRgn( hdc, visrgn, SYSRGN);
  80     if( !(GetVersion() & 0x80000000)) {
  81         /* Window NT/2k/XP */
  82         POINT org;
  83         GetDCOrgEx(hdc, &org);
  84         OffsetRgn( visrgn, -org.x, -org.y);
  85     }
  86     /* intersect with the clipping Region if the DC has one */
  87     clipRgn = CreateRectRgn( 0, 0, 0, 0);
  88     if (GetClipRgn( hdc, clipRgn) != 1) {
  89         DeleteObject(clipRgn);
  90         clipRgn=NULL;
  91     } else
  92         CombineRgn( visrgn, visrgn, clipRgn, RGN_AND);
  93     /* only those pixels in the scroll rectangle that remain in the clipping
  94      * rect are scrolled. */
  95     if( lprcClip)
  96         rcClip = *lprcClip;
  97     else
  98         GetClipBox( hdc, &rcClip);
  99     rcSrc = rcClip;
 100     OffsetRect( &rcClip, -dx, -dy);
 101     IntersectRect( &rcSrc, &rcSrc, &rcClip);
 102     /* if an scroll rectangle is specified, only the pixels within that
 103      * rectangle are scrolled */
 104     if( lprcScroll)
 105         IntersectRect( &rcSrc, &rcSrc, lprcScroll);
 106     /* now convert to device coordinates */
 107     LPtoDP(hdc, (LPPOINT)&rcSrc, 2);
 108     TRACE("source rect: %s\n", wine_dbgstr_rect(&rcSrc));
 109     /* also dx and dy */
 110     SetRect(&offset, 0, 0, dx, dy);
 111     LPtoDP(hdc, (LPPOINT)&offset, 2);
 112     dxdev = offset.right - offset.left;
 113     dydev = offset.bottom - offset.top;
 114     /* now intersect with the visible region to get the pixels that will
 115      * actually scroll */
 116     DstRgn = CreateRectRgnIndirect( &rcSrc);
 117     res = CombineRgn( DstRgn, DstRgn, visrgn, RGN_AND);
 118     /* and translate, giving the destination region */
 119     OffsetRgn( DstRgn, dxdev, dydev);
 120     if( TRACE_ON( scroll)) dump_region( "Destination scroll region: ", DstRgn);
 121     /* if there are any, do it */
 122     if( res > NULLREGION) {
 123         RECT rect ;
 124         /* clip to the destination region, so we can BitBlt with a simple
 125          * bounding rectangle */
 126         if( clipRgn)
 127             ExtSelectClipRgn( hdc, DstRgn, RGN_AND);
 128         else
 129             SelectClipRgn( hdc, DstRgn);
 130         GetRgnBox( DstRgn, &rect);
 131         DPtoLP(hdc, (LPPOINT)&rect, 2);
 132         TRACE("destination rect: %s\n", wine_dbgstr_rect(&rect));
 133
 134         BitBlt( hdc, rect.left, rect.top,
 135                     rect.right - rect.left, rect.bottom - rect.top,
 136                     hdc, rect.left - dx, rect.top - dy, SRCCOPY);
 137     }
 138     /* compute the update areas.  This is the combined clip rectangle
 139      * minus the scrolled region, and intersected with the visible
 140      * region. */
 141     if (hrgnUpdate || lprcUpdate)
 142     {
 143         HRGN hrgn = hrgnUpdate;
 144         HRGN ExpRgn = 0;
 145
 146         /* collect all the exposures */
 147         code = X11DRV_END_EXPOSURES;
 148         ExtEscape( hdc, X11DRV_ESCAPE, sizeof(code), (LPSTR)&code,
 149                 sizeof(ExpRgn), (LPSTR)&ExpRgn );
 150         /* Intersect clip and scroll rectangles, allowing NULL values */
 151         if( lprcScroll)
 152             if( lprcClip)
 153                 IntersectRect( &rcClip, lprcClip, lprcScroll);
 154             else
 155                 rcClip = *lprcScroll;
 156         else
 157             if( lprcClip)
 158                 rcClip = *lprcClip;
 159             else
 160                 GetClipBox( hdc, &rcClip);
 161         /* Convert the combined clip rectangle to device coordinates */
 162         LPtoDP(hdc, (LPPOINT)&rcClip, 2);
 163         if( hrgn )
 164             SetRectRgn( hrgn, rcClip.left, rcClip.top, rcClip.right,
 165                     rcClip.bottom);
 166         else
 167             hrgn = CreateRectRgnIndirect( &rcClip);
 168         CombineRgn( hrgn, hrgn, visrgn, RGN_AND);
 169         CombineRgn( hrgn, hrgn, DstRgn, RGN_DIFF);
 170         /* add the exposures to this */
 171         if( ExpRgn) {
 172             if( TRACE_ON( scroll)) dump_region( "Expose region: ", ExpRgn);
 173             CombineRgn( hrgn, hrgn, ExpRgn, RGN_OR);
 174             DeleteObject( ExpRgn);
 175         }
 176         if( TRACE_ON( scroll)) dump_region( "Update region: ", hrgn);
 177         if( lprcUpdate) {
 178             GetRgnBox( hrgn, lprcUpdate );
 179             /* Put the lprcUpdate in logical coordinates */
 180             DPtoLP( hdc, (LPPOINT)lprcUpdate, 2 );
 181             TRACE("returning lprcUpdate %s\n", wine_dbgstr_rect(lprcUpdate));
 182         }
 183         if( !hrgnUpdate)
 184             DeleteObject( hrgn);
 185     }
 186     /* restore original clipping region */
 187     SelectClipRgn( hdc, clipRgn);
 188     DeleteObject( visrgn);
 189     DeleteObject( DstRgn);
 190     if( clipRgn) DeleteObject( clipRgn);
 191     return TRUE;
 192 }