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 <stdlib.h>
  23
  24 #include "windef.h"
  25 #include "wingdi.h"
  26 #include "wine/winuser16.h"
  27 #include "winuser.h"
  28 #include "user.h"
  29 #include "win.h"
  30 #include "wine/debug.h"
  31
  32 WINE_DEFAULT_DEBUG_CHANNEL(scroll);
  33
  34 /*************************************************************************
  35  *             fix_caret
  36  */
  37 static HWND fix_caret(HWND hWnd, LPRECT lprc, UINT flags)
  38 {
  39    HWND hCaret = CARET_GetHwnd();
  40
  41    if( hCaret )
  42    {
  43        RECT rc;
  44        CARET_GetRect( &rc );
  45        if( hCaret == hWnd ||
  46           (flags & SW_SCROLLCHILDREN && IsChild(hWnd, hCaret)) )
  47        {
  48            POINT pt;
  49            pt.x = rc.left;
  50            pt.y = rc.top;
  51            MapWindowPoints( hCaret, hWnd, (LPPOINT)&rc, 2 );
  52            if( IntersectRect(lprc, lprc, &rc) )
  53            {
  54                HideCaret(hCaret);
  55                lprc->left = pt.x;
  56                lprc->top = pt.y;
  57                return hCaret;
  58            }
  59        }
  60    }
  61    return 0;
  62 }
  63
  64
  65 /*************************************************************************
  66  *              ScrollWindow (USER32.@)
  67  *
  68  */
  69 BOOL WINAPI ScrollWindow( HWND hwnd, INT dx, INT dy,
  70                               const RECT *rect, const RECT *clipRect )
  71 {
  72     return
  73         (ERROR != ScrollWindowEx( hwnd, dx, dy, rect, clipRect, 0, NULL,
  74                                     (rect ? 0 : SW_SCROLLCHILDREN) |
  75                                     SW_INVALIDATE ));
  76 }
  77
  78 /*************************************************************************
  79  *              ScrollDC (USER.221)
  80  */
  81 BOOL16 WINAPI ScrollDC16( HDC16 hdc, INT16 dx, INT16 dy, const RECT16 *rect,
  82                           const RECT16 *cliprc, HRGN16 hrgnUpdate,
  83                           LPRECT16 rcUpdate )
  84 {
  85     RECT rect32, clipRect32, rcUpdate32;
  86     BOOL16 ret;
  87
  88     if (rect) CONV_RECT16TO32( rect, &rect32 );
  89     if (cliprc) CONV_RECT16TO32( cliprc, &clipRect32 );
  90     ret = ScrollDC( hdc, dx, dy, rect ? &rect32 : NULL,
  91                       cliprc ? &clipRect32 : NULL, hrgnUpdate, &rcUpdate32 );
  92     if (rcUpdate) CONV_RECT32TO16( &rcUpdate32, rcUpdate );
  93     return ret;
  94 }
  95
  96
  97 /*************************************************************************
  98  *              ScrollDC (USER32.@)
  99  *
 100  *   Only the hrgnUpdate is return in device coordinate.
 101  *   rcUpdate must be returned in logical coordinate to comply with win API.
 102  *
 103  */
 104 BOOL WINAPI ScrollDC( HDC hdc, INT dx, INT dy, const RECT *rc,
 105                           const RECT *prLClip, HRGN hrgnUpdate,
 106                           LPRECT rcUpdate )
 107 {
 108     if (USER_Driver.pScrollDC)
 109         return USER_Driver.pScrollDC( hdc, dx, dy, rc, prLClip, hrgnUpdate, rcUpdate );
 110     return FALSE;
 111 }
 112
 113
 114 /*************************************************************************
 115  *              ScrollWindowEx (USER32.@)
 116  *
 117  * NOTE: Use this function instead of ScrollWindow32
 118  */
 119 INT WINAPI ScrollWindowEx( HWND hwnd, INT dx, INT dy,
 120                                const RECT *rect, const RECT *clipRect,
 121                                HRGN hrgnUpdate, LPRECT rcUpdate,
 122                                UINT flags )
 123 {
 124     RECT rc, cliprc;
 125     INT result;
 126
 127     if (!WIN_IsWindowDrawable( hwnd, TRUE )) return ERROR;
 128     hwnd = WIN_GetFullHandle( hwnd );
 129
 130     GetClientRect(hwnd, &rc);
 131     if (rect) IntersectRect(&rc, &rc, rect);
 132
 133     if (clipRect) IntersectRect(&cliprc,&rc,clipRect);
 134     else cliprc = rc;
 135
 136     if (!IsRectEmpty(&cliprc) && (dx || dy))
 137     {
 138         RECT caretrc = rc;
 139         HWND hwndCaret = fix_caret(hwnd, &caretrc, flags);
 140
 141         if (USER_Driver.pScrollWindowEx)
 142             result = USER_Driver.pScrollWindowEx( hwnd, dx, dy, &rc, &cliprc,
 143                                                   hrgnUpdate, rcUpdate, flags );
 144         else
 145             result = ERROR; /* FIXME: we should have a fallback implementation */
 146
 147         if( hwndCaret )
 148         {
 149             SetCaretPos( caretrc.left + dx, caretrc.top + dy );
 150             ShowCaret(hwndCaret);
 151         }
 152     }
 153     else
 154         result = NULLREGION;
 155
 156     return result;
 157 }