dlls/winemac.drv/scroll.c

   1 /*
   2  * MACDRV window/DC scrolling
   3  *
   4  * Copyright 1993  David W. Metcalfe
   5  * Copyright 1995, 1996 Alex Korobka
   6  * Copyright 2001 Alexandre Julliard
   7  * Copyright 2011, 2013 Ken Thomases for CodeWeavers Inc.
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  22  */
  23
  24 #include "config.h"
  25
  26 #include "macdrv.h"
  27 #include "winuser.h"
  28
  29 WINE_DEFAULT_DEBUG_CHANNEL(scroll);
  30
  31
  32 static void dump_region(const char *p, HRGN hrgn)
  33 {
  34     DWORD i, size;
  35     RGNDATA *data = NULL;
  36     RECT *rect;
  37
  38     if (!hrgn)
  39     {
  40         TRACE("%s null region\n", p);
  41         return;
  42     }
  43     if (!(size = GetRegionData(hrgn, 0, NULL)))
  44         return;
  45     if (!(data = HeapAlloc(GetProcessHeap(), 0, size))) return;
  46     GetRegionData(hrgn, size, data);
  47     TRACE("%s %d rects:", p, data->rdh.nCount);
  48     for (i = 0, rect = (RECT *)data->Buffer; i<20 && i < data->rdh.nCount; i++, rect++)
  49         TRACE(" %s", wine_dbgstr_rect(rect));
  50     TRACE("\n");
  51     HeapFree(GetProcessHeap(), 0, data);
  52 }
  53
  54
  55 /*************************************************************************
  56  *              ScrollDC   (MACDRV.@)
  57  */
  58 BOOL CDECL macdrv_ScrollDC(HDC hdc, INT dx, INT dy, const RECT *lprcScroll,
  59                            const RECT *lprcClip, HRGN hrgnUpdate, LPRECT lprcUpdate)
  60 {
  61     RECT rcSrc, rcClip, offset;
  62     INT dxdev, dydev, res;
  63     HRGN DstRgn, clipRgn, visrgn;
  64
  65     TRACE("dx,dy %d,%d rcScroll %s rcClip %s hrgnUpdate %p lprcUpdate %p\n",
  66           dx, dy, wine_dbgstr_rect(lprcScroll), wine_dbgstr_rect(lprcClip),
  67           hrgnUpdate, lprcUpdate);
  68
  69     /* get the visible region */
  70     visrgn = CreateRectRgn(0, 0, 0, 0);
  71     GetRandomRgn(hdc, visrgn, SYSRGN);
  72     if (!(GetVersion() & 0x80000000))
  73     {
  74         /* Window NT/2k/XP */
  75         POINT org;
  76         GetDCOrgEx(hdc, &org);
  77         OffsetRgn(visrgn, -org.x, -org.y);
  78     }
  79
  80     /* intersect with the clipping Region if the DC has one */
  81     clipRgn = CreateRectRgn(0, 0, 0, 0);
  82     if (GetClipRgn(hdc, clipRgn) != 1)
  83     {
  84         DeleteObject(clipRgn);
  85         clipRgn = NULL;
  86     }
  87     else
  88         CombineRgn(visrgn, visrgn, clipRgn, RGN_AND);
  89
  90     /* only those pixels in the scroll rectangle that remain in the clipping
  91      * rect are scrolled. */
  92     if (lprcClip)
  93         rcClip = *lprcClip;
  94     else
  95         GetClipBox(hdc, &rcClip);
  96     rcSrc = rcClip;
  97     OffsetRect(&rcClip, -dx, -dy);
  98     IntersectRect(&rcSrc, &rcSrc, &rcClip);
  99
 100     /* if an scroll rectangle is specified, only the pixels within that
 101      * rectangle are scrolled */
 102     if (lprcScroll)
 103         IntersectRect(&rcSrc, &rcSrc, lprcScroll);
 104
 105     /* now convert to device coordinates */
 106     LPtoDP(hdc, (LPPOINT)&rcSrc, 2);
 107     TRACE("source rect: %s\n", wine_dbgstr_rect(&rcSrc));
 108
 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
 115     /* now intersect with the visible region to get the pixels that will
 116      * actually scroll */
 117     DstRgn = CreateRectRgnIndirect(&rcSrc);
 118     res = CombineRgn(DstRgn, DstRgn, visrgn, RGN_AND);
 119
 120     /* and translate, giving the destination region */
 121     OffsetRgn(DstRgn, dxdev, dydev);
 122     if (TRACE_ON(scroll)) dump_region("Destination scroll region: ", DstRgn);
 123
 124     /* if there are any, do it */
 125     if (res > NULLREGION)
 126     {
 127         RECT rect ;
 128         /* clip to the destination region, so we can BitBlt with a simple
 129          * bounding rectangle */
 130         if (clipRgn)
 131             ExtSelectClipRgn(hdc, DstRgn, RGN_AND);
 132         else
 133             SelectClipRgn(hdc, DstRgn);
 134         GetRgnBox(DstRgn, &rect);
 135         DPtoLP(hdc, (LPPOINT)&rect, 2);
 136         TRACE("destination rect: %s\n", wine_dbgstr_rect(&rect));
 137
 138         BitBlt(hdc, rect.left, rect.top,
 139                rect.right - rect.left, rect.bottom - rect.top,
 140                hdc, rect.left - dx, rect.top - dy, SRCCOPY);
 141     }
 142
 143     /* compute the update areas.  This is the combined clip rectangle
 144      * minus the scrolled region, and intersected with the visible
 145      * region. */
 146     if (hrgnUpdate || lprcUpdate)
 147     {
 148         HRGN hrgn = hrgnUpdate;
 149
 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
 162         /* Convert the combined clip rectangle to device coordinates */
 163         LPtoDP(hdc, (LPPOINT)&rcClip, 2);
 164         if (hrgn)
 165             SetRectRgn(hrgn, rcClip.left, rcClip.top, rcClip.right, rcClip.bottom);
 166         else
 167             hrgn = CreateRectRgnIndirect(&rcClip);
 168         CombineRgn(hrgn, hrgn, visrgn, RGN_AND);
 169         CombineRgn(hrgn, hrgn, DstRgn, RGN_DIFF);
 170         if (TRACE_ON(scroll)) dump_region("Update region: ", hrgn);
 171         if (lprcUpdate)
 172         {
 173             GetRgnBox(hrgn, lprcUpdate);
 174             /* Put the lprcUpdate in logical coordinates */
 175             DPtoLP(hdc, (LPPOINT)lprcUpdate, 2);
 176             TRACE("returning lprcUpdate %s\n", wine_dbgstr_rect(lprcUpdate));
 177         }
 178         if (!hrgnUpdate)
 179             DeleteObject(hrgn);
 180     }
 181
 182     /* restore original clipping region */
 183     SelectClipRgn(hdc, clipRgn);
 184     DeleteObject(visrgn);
 185     DeleteObject(DstRgn);
 186     if (clipRgn) DeleteObject(clipRgn);
 187     return TRUE;
 188 }