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_private.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  *              ScrollWindowEx (USER32.@)
  65  *
  66  * Note: contrary to what the doc says, pixels that are scrolled from the
  67  *      outside of clipRect to the inside are NOT painted.
  68  *
  69  */
  70 INT WINAPI ScrollWindowEx( HWND hwnd, INT dx, INT dy,
  71                                const RECT *rect, const RECT *clipRect,
  72                                HRGN hrgnUpdate, LPRECT rcUpdate,
  73                                UINT flags )
  74 {
  75     INT   retVal = NULLREGION;
  76     BOOL  bOwnRgn = TRUE;
  77     BOOL  bUpdate = (rcUpdate || hrgnUpdate || flags & (SW_INVALIDATE | SW_ERASE));
  78     int rdw_flags;
  79     HRGN  hrgnTemp;
  80     HDC   hDC;
  81     RECT  rc, cliprc;
  82     RECT caretrc;
  83     HWND hwndCaret = NULL;
  84
  85     TRACE( "%p, %d,%d hrgnUpdate=%p rcUpdate = %p %s %04x\n",
  86            hwnd, dx, dy, hrgnUpdate, rcUpdate, wine_dbgstr_rect(rect), flags );
  87     TRACE( "clipRect = %s\n", wine_dbgstr_rect(clipRect));
  88     if( flags & ~( SW_SCROLLCHILDREN | SW_INVALIDATE | SW_ERASE))
  89         FIXME("some flags (%04x) are unhandled\n", flags);
  90
  91     rdw_flags = (flags & SW_ERASE) && (flags & SW_INVALIDATE) ?
  92                                 RDW_INVALIDATE | RDW_ERASE  : RDW_INVALIDATE ;
  93
  94     if (!WIN_IsWindowDrawable( hwnd, TRUE )) return ERROR;
  95     hwnd = WIN_GetFullHandle( hwnd );
  96
  97     GetClientRect(hwnd, &rc);
  98     if (rect) IntersectRect(&rc, &rc, rect);
  99
 100     if (clipRect) IntersectRect(&cliprc,&rc,clipRect);
 101     else cliprc = rc;
 102
 103     if( hrgnUpdate ) bOwnRgn = FALSE;
 104     else if( bUpdate ) hrgnUpdate = CreateRectRgn( 0, 0, 0, 0 );
 105
 106     if( !IsRectEmpty(&cliprc) && (dx || dy)) {
 107         caretrc = rc;
 108         hwndCaret = fix_caret(hwnd, &caretrc, flags);
 109
 110         hDC = GetDCEx( hwnd, 0, DCX_CACHE | DCX_USESTYLE );
 111         if (hDC)
 112         {
 113             ScrollDC( hDC, dx, dy, &rc, &cliprc, hrgnUpdate, rcUpdate );
 114
 115             ReleaseDC( hwnd, hDC );
 116
 117             if (!bUpdate)
 118                 RedrawWindow( hwnd, NULL, hrgnUpdate, rdw_flags);
 119         }
 120
 121         /* Take into account the fact that some damage may have occurred during
 122          * the scroll */
 123         hrgnTemp = CreateRectRgn( 0, 0, 0, 0 );
 124         retVal = GetUpdateRgn( hwnd, hrgnTemp, FALSE );
 125         if (retVal != NULLREGION)
 126         {
 127             HRGN hrgnClip = CreateRectRgnIndirect(&cliprc);
 128             OffsetRgn( hrgnTemp, dx, dy );
 129             CombineRgn( hrgnTemp, hrgnTemp, hrgnClip, RGN_AND );
 130             RedrawWindow( hwnd, NULL, hrgnTemp, rdw_flags);
 131             DeleteObject( hrgnClip );
 132         }
 133         DeleteObject( hrgnTemp );
 134     } else {
 135         /* nothing was scrolled */
 136         if( !bOwnRgn)
 137             SetRectRgn( hrgnUpdate, 0, 0, 0, 0 );
 138         SetRectEmpty( rcUpdate);
 139     }
 140
 141     if( flags & SW_SCROLLCHILDREN )
 142     {
 143         HWND *list = WIN_ListChildren( hwnd );
 144         if (list)
 145         {
 146             int i;
 147             RECT r, dummy;
 148             for (i = 0; list[i]; i++)
 149             {
 150                 GetWindowRect( list[i], &r );
 151                 MapWindowPoints( 0, hwnd, (POINT *)&r, 2 );
 152                 if (!rect || IntersectRect(&dummy, &r, rect))
 153                     SetWindowPos( list[i], 0, r.left + dx, r.top  + dy, 0, 0,
 154                                   SWP_NOZORDER | SWP_NOSIZE | SWP_NOACTIVATE |
 155                                   SWP_NOREDRAW | SWP_DEFERERASE );
 156             }
 157             HeapFree( GetProcessHeap(), 0, list );
 158         }
 159     }
 160
 161     if( flags & (SW_INVALIDATE | SW_ERASE) )
 162         RedrawWindow( hwnd, NULL, hrgnUpdate, rdw_flags |
 163                       ((flags & SW_SCROLLCHILDREN) ? RDW_ALLCHILDREN : 0 ) );
 164
 165     if( hwndCaret ) {
 166         SetCaretPos( caretrc.left + dx, caretrc.top + dy );
 167         ShowCaret(hwndCaret);
 168     }
 169
 170     if( bOwnRgn && hrgnUpdate ) DeleteObject( hrgnUpdate );
 171
 172     return retVal;
 173 }
 174
 175 /*************************************************************************
 176  *              ScrollWindow (USER32.@)
 177  *
 178  */
 179 BOOL WINAPI ScrollWindow( HWND hwnd, INT dx, INT dy,
 180                               const RECT *rect, const RECT *clipRect )
 181 {
 182     return
 183         (ERROR != ScrollWindowEx( hwnd, dx, dy, rect, clipRect, 0, NULL,
 184                                     (rect ? 0 : SW_SCROLLCHILDREN) |
 185                                     SW_INVALIDATE ));
 186 }
 187
 188 /*************************************************************************
 189  *              ScrollDC (USER32.@)
 190  *
 191  * dx, dy, lprcScroll and lprcClip are all in logical coordinates (msdn is
 192  * wrong) hrgnUpdate is returned in device coordinates with rcUpdate in
 193  * logical coordinates.
 194  */
 195 BOOL WINAPI ScrollDC( HDC hdc, INT dx, INT dy, const RECT *lprcScroll,
 196                       const RECT *lprcClip, HRGN hrgnUpdate, LPRECT lprcUpdate )
 197
 198 {
 199     if (USER_Driver.pScrollDC)
 200         return USER_Driver.pScrollDC( hdc, dx, dy, lprcScroll, lprcClip, hrgnUpdate, lprcUpdate );
 201     return FALSE;
 202 }