windows/scroll.c

   1 /*
   2  * Scroll windows and DCs
   3  *
   4  * Copyright  David W. Metcalfe, 1993
   5  *            Alex Korobka       1995,1996
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include <stdarg.h>
  23 #include <stdlib.h>
  24
  25 #include "windef.h"
  26 #include "winbase.h"
  27 #include "wingdi.h"
  28 #include "wine/winuser16.h"
  29 #include "winuser.h"
  30 #include "user.h"
  31 #include "win.h"
  32 #include "wine/debug.h"
  33
  34 WINE_DEFAULT_DEBUG_CHANNEL(scroll);
  35
  36 /*************************************************************************
  37  *             fix_caret
  38  */
  39 static HWND fix_caret(HWND hWnd, LPRECT lprc, UINT flags)
  40 {
  41     GUITHREADINFO info;
  42
  43     if (!GetGUIThreadInfo( GetCurrentThreadId(), &info )) return 0;
  44     if (!info.hwndCaret) return 0;
  45     if (info.hwndCaret == hWnd ||
  46         ((flags & SW_SCROLLCHILDREN) && IsChild(hWnd, info.hwndCaret)))
  47     {
  48         POINT pt;
  49         pt.x = info.rcCaret.left;
  50         pt.y = info.rcCaret.top;
  51         MapWindowPoints( info.hwndCaret, hWnd, (LPPOINT)&info.rcCaret, 2 );
  52         if( IntersectRect(lprc, lprc, &info.rcCaret) )
  53         {
  54             HideCaret(0);
  55             lprc->left = pt.x;
  56             lprc->top = pt.y;
  57             return info.hwndCaret;
  58         }
  59     }
  60     return 0;
  61 }
  62
  63
  64 /*************************************************************************
  65  *              ScrollWindow (USER32.@)
  66  *
  67  */
  68 BOOL WINAPI ScrollWindow( HWND hwnd, INT dx, INT dy,
  69                               const RECT *rect, const RECT *clipRect )
  70 {
  71     return
  72         (ERROR != ScrollWindowEx( hwnd, dx, dy, rect, clipRect, 0, NULL,
  73                                     (rect ? 0 : SW_SCROLLCHILDREN) |
  74                                     SW_INVALIDATE ));
  75 }
  76
  77 /*************************************************************************
  78  *              ScrollDC (USER32.@)
  79  *
  80  * dx, dy, lprcScroll and lprcClip are all in logical coordinates (msdn is wrong)
  81  * hrgnUpdate is returned in device coordinates with rcUpdate in logical coordinates.
  82  */
  83 BOOL WINAPI ScrollDC( HDC hdc, INT dx, INT dy, const RECT *lprcScroll,
  84                       const RECT *lprcClip, HRGN hrgnUpdate, LPRECT lprcUpdate )
  85
  86 {
  87     RECT rSrc, rClipped_src, rClip, rDst, offset;
  88
  89     TRACE( "%p %d,%d hrgnUpdate=%p lprcUpdate = %p\n", hdc, dx, dy, hrgnUpdate, lprcUpdate );
  90     if (lprcClip) TRACE( "lprcClip = %s\n", wine_dbgstr_rect(lprcClip));
  91     if (lprcScroll) TRACE( "lprcScroll = %s\n", wine_dbgstr_rect(lprcScroll));
  92
  93     /* compute device clipping region (in device coordinates) */
  94
  95     if (lprcScroll) rSrc = *lprcScroll;
  96     else GetClipBox( hdc, &rSrc );
  97     LPtoDP(hdc, (LPPOINT)&rSrc, 2);
  98
  99     if (lprcClip) rClip = *lprcClip;
 100     else GetClipBox( hdc, &rClip );
 101     LPtoDP(hdc, (LPPOINT)&rClip, 2);
 102
 103     IntersectRect( &rClipped_src, &rSrc, &rClip );
 104     TRACE("rSrc %s rClip %s clipped rSrc %s\n", wine_dbgstr_rect(&rSrc),
 105           wine_dbgstr_rect(&rClip), wine_dbgstr_rect(&rClipped_src));
 106
 107     rDst = rClipped_src;
 108     SetRect(&offset, 0, 0, dx, dy);
 109     LPtoDP(hdc, (LPPOINT)&offset, 2);
 110     OffsetRect( &rDst, offset.right - offset.left,  offset.bottom - offset.top );
 111     TRACE("rDst before clipping %s\n", wine_dbgstr_rect(&rDst));
 112     IntersectRect( &rDst, &rDst, &rClip );
 113     TRACE("rDst after clipping %s\n", wine_dbgstr_rect(&rDst));
 114
 115     if (!IsRectEmpty(&rDst))
 116     {
 117         /* copy bits */
 118         RECT rDst_lp = rDst, rSrc_lp = rDst;
 119
 120         OffsetRect( &rSrc_lp, offset.left - offset.right, offset.top - offset.bottom );
 121         DPtoLP(hdc, (LPPOINT)&rDst_lp, 2);
 122         DPtoLP(hdc, (LPPOINT)&rSrc_lp, 2);
 123
 124         if (!BitBlt( hdc, rDst_lp.left, rDst_lp.top,
 125                      rDst_lp.right - rDst_lp.left, rDst_lp.bottom - rDst_lp.top,
 126                      hdc, rSrc_lp.left, rSrc_lp.top, SRCCOPY))
 127             return FALSE;
 128     }
 129
 130     /* compute update areas.  This is the clipped source or'ed with the unclipped source translated minus the
 131      clipped src translated (rDst) all clipped to rClip */
 132
 133     if (hrgnUpdate || lprcUpdate)
 134     {
 135         HRGN hrgn = hrgnUpdate, hrgn2;
 136
 137         if (hrgn) SetRectRgn( hrgn, rClipped_src.left, rClipped_src.top, rClipped_src.right, rClipped_src.bottom );
 138         else hrgn = CreateRectRgn( rClipped_src.left, rClipped_src.top, rClipped_src.right, rClipped_src.bottom );
 139
 140         hrgn2 = CreateRectRgnIndirect( &rSrc );
 141         OffsetRgn(hrgn2, offset.right - offset.left,  offset.bottom - offset.top );
 142         CombineRgn(hrgn, hrgn, hrgn2, RGN_OR);
 143
 144         SetRectRgn( hrgn2, rDst.left, rDst.top, rDst.right, rDst.bottom );
 145         CombineRgn( hrgn, hrgn, hrgn2, RGN_DIFF );
 146
 147         SetRectRgn( hrgn2, rClip.left, rClip.top, rClip.right, rClip.bottom );
 148         CombineRgn( hrgn, hrgn, hrgn2, RGN_AND );
 149
 150         if( lprcUpdate )
 151         {
 152             GetRgnBox( hrgn, lprcUpdate );
 153
 154             /* Put the lprcUpdate in logical coordinate */
 155             DPtoLP( hdc, (LPPOINT)lprcUpdate, 2 );
 156             TRACE("returning lprcUpdate %s\n", wine_dbgstr_rect(lprcUpdate));
 157         }
 158         if (!hrgnUpdate) DeleteObject( hrgn );
 159         DeleteObject( hrgn2 );
 160     }
 161     return TRUE;
 162 }
 163
 164
 165 /*************************************************************************
 166  *              ScrollWindowEx (USER32.@)
 167  *
 168  * NOTE: Use this function instead of ScrollWindow32
 169  */
 170 INT WINAPI ScrollWindowEx( HWND hwnd, INT dx, INT dy,
 171                                const RECT *rect, const RECT *clipRect,
 172                                HRGN hrgnUpdate, LPRECT rcUpdate,
 173                                UINT flags )
 174 {
 175     RECT rc, cliprc;
 176     INT result;
 177
 178     if (!WIN_IsWindowDrawable( hwnd, TRUE )) return ERROR;
 179     hwnd = WIN_GetFullHandle( hwnd );
 180
 181     GetClientRect(hwnd, &rc);
 182     if (rect) IntersectRect(&rc, &rc, rect);
 183
 184     if (clipRect) IntersectRect(&cliprc,&rc,clipRect);
 185     else cliprc = rc;
 186
 187     if (!IsRectEmpty(&cliprc) && (dx || dy))
 188     {
 189         RECT caretrc = rc;
 190         HWND hwndCaret = fix_caret(hwnd, &caretrc, flags);
 191
 192         if (USER_Driver.pScrollWindowEx)
 193             result = USER_Driver.pScrollWindowEx( hwnd, dx, dy, rect, clipRect,
 194                                                   hrgnUpdate, rcUpdate, flags );
 195         else
 196             result = ERROR; /* FIXME: we should have a fallback implementation */
 197
 198         if( hwndCaret )
 199         {
 200             SetCaretPos( caretrc.left + dx, caretrc.top + dy );
 201             ShowCaret(hwndCaret);
 202         }
 203     }
 204     else
 205         result = NULLREGION;
 206
 207     return result;
 208 }