dlls/user/painting.c

   1 /*
   2  * Window painting functions
   3  *
   4  * Copyright 1993, 1994, 1995, 2001 Alexandre Julliard
   5  * Copyright 1999 Alex Korobka
   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 #include <string.h>
  22
  23 #include "windef.h"
  24 #include "wingdi.h"
  25 #include "wine/winuser16.h"
  26 #include "wine/server.h"
  27 #include "win.h"
  28 #include "dce.h"
  29 #include "wine/debug.h"
  30
  31 WINE_DEFAULT_DEBUG_CHANNEL(win);
  32
  33 /***********************************************************************
  34  *           add_paint_count
  35  *
  36  * Add an increment (normally 1 or -1) to the current paint count of a window.
  37  */
  38 static void add_paint_count( HWND hwnd, int incr )
  39 {
  40     SERVER_START_REQ( inc_window_paint_count )
  41     {
  42         req->handle = hwnd;
  43         req->incr   = incr;
  44         wine_server_call( req );
  45     }
  46     SERVER_END_REQ;
  47 }
  48
  49
  50 /***********************************************************************
  51  *           copy_rgn
  52  *
  53  * copy a region, doing the right thing if the source region is 0 or 1
  54  */
  55 static HRGN copy_rgn( HRGN hSrc )
  56 {
  57     if (hSrc > (HRGN)1)
  58     {
  59         HRGN hrgn = CreateRectRgn( 0, 0, 0, 0 );
  60         CombineRgn( hrgn, hSrc, 0, RGN_COPY );
  61         return hrgn;
  62     }
  63     return hSrc;
  64 }
  65
  66
  67 /***********************************************************************
  68  *           get_update_regions
  69  *
  70  * Return update regions for the whole window and for the client area.
  71  */
  72 static void get_update_regions( WND *win, HRGN *whole_rgn, HRGN *client_rgn )
  73 {
  74     if (win->hrgnUpdate > (HRGN)1)
  75     {
  76         RECT client, update;
  77
  78         /* check if update rgn overlaps with nonclient area */
  79         GetRgnBox( win->hrgnUpdate, &update );
  80         client = win->rectClient;
  81         OffsetRect( &client, -win->rectWindow.left, -win->rectWindow.top );
  82
  83         if (update.left < client.left || update.top < client.top ||
  84             update.right > client.right || update.bottom > client.bottom)
  85         {
  86             *whole_rgn = copy_rgn( win->hrgnUpdate );
  87             *client_rgn = CreateRectRgnIndirect( &client );
  88             if (CombineRgn( *client_rgn, *client_rgn, win->hrgnUpdate, RGN_AND ) == NULLREGION)
  89             {
  90                 DeleteObject( *client_rgn );
  91                 *client_rgn = 0;
  92             }
  93         }
  94         else
  95         {
  96             *whole_rgn = 0;
  97             *client_rgn = copy_rgn( win->hrgnUpdate );
  98         }
  99     }
 100     else
 101     {
 102         *client_rgn = *whole_rgn = win->hrgnUpdate;  /* 0 or 1 */
 103     }
 104 }
 105
 106
 107 /***********************************************************************
 108  *           begin_ncpaint
 109  *
 110  * Send a WM_NCPAINT message from inside BeginPaint().
 111  * Returns update region cropped to client rectangle (and in client coords),
 112  * and clears window update region and internal paint flag.
 113  */
 114 static HRGN begin_ncpaint( HWND hwnd )
 115 {
 116     HRGN whole_rgn, client_rgn;
 117     WND *wnd = WIN_GetPtr( hwnd );
 118
 119     if (!wnd || wnd == WND_OTHER_PROCESS) return 0;
 120
 121     TRACE("hwnd %p [%p] ncf %i\n",
 122           hwnd, wnd->hrgnUpdate, wnd->flags & WIN_NEEDS_NCPAINT);
 123
 124     get_update_regions( wnd, &whole_rgn, &client_rgn );
 125
 126     if (whole_rgn) /* NOTE: WM_NCPAINT allows wParam to be 1 */
 127     {
 128         WIN_ReleasePtr( wnd );
 129         SendMessageA( hwnd, WM_NCPAINT, (WPARAM)whole_rgn, 0 );
 130         if (whole_rgn > (HRGN)1) DeleteObject( whole_rgn );
 131         /* make sure the window still exists before continuing */
 132         if (!(wnd = WIN_GetPtr( hwnd )) || wnd == WND_OTHER_PROCESS)
 133         {
 134             if (client_rgn > (HRGN)1) DeleteObject( client_rgn );
 135             return 0;
 136         }
 137     }
 138
 139     if (wnd->hrgnUpdate || (wnd->flags & WIN_INTERNAL_PAINT)) add_paint_count( hwnd, -1 );
 140     if (wnd->hrgnUpdate > (HRGN)1) DeleteObject( wnd->hrgnUpdate );
 141     wnd->hrgnUpdate = 0;
 142     wnd->flags &= ~(WIN_INTERNAL_PAINT | WIN_NEEDS_NCPAINT | WIN_NEEDS_BEGINPAINT);
 143     if (client_rgn > (HRGN)1) OffsetRgn( client_rgn, wnd->rectWindow.left - wnd->rectClient.left,
 144                                          wnd->rectWindow.top - wnd->rectClient.top );
 145     WIN_ReleasePtr( wnd );
 146     return client_rgn;
 147 }
 148
 149
 150 /***********************************************************************
 151  *              BeginPaint (USER32.@)
 152  */
 153 HDC WINAPI BeginPaint( HWND hwnd, PAINTSTRUCT *lps )
 154 {
 155     INT dcx_flags;
 156     BOOL bIcon;
 157     HRGN hrgnUpdate;
 158     RECT clipRect, clientRect;
 159     HWND full_handle;
 160     WND *wndPtr;
 161
 162     if (!lps) return 0;
 163
 164     if (!(full_handle = WIN_IsCurrentThread( hwnd )))
 165     {
 166         if (IsWindow(hwnd))
 167             FIXME( "window %p belongs to other thread\n", hwnd );
 168         return 0;
 169     }
 170     hwnd = full_handle;
 171
 172     /* send WM_NCPAINT and retrieve update region */
 173     hrgnUpdate = begin_ncpaint( hwnd );
 174     if (!hrgnUpdate && !IsWindow( hwnd )) return 0;
 175
 176     HideCaret( hwnd );
 177
 178     bIcon = (IsIconic(hwnd) && GetClassLongA(hwnd, GCL_HICON));
 179
 180     dcx_flags = DCX_INTERSECTRGN | DCX_WINDOWPAINT | DCX_USESTYLE;
 181     if (bIcon) dcx_flags |= DCX_WINDOW;
 182
 183     if (GetClassLongA( hwnd, GCL_STYLE ) & CS_PARENTDC)
 184     {
 185         /* Don't clip the output to the update region for CS_PARENTDC window */
 186         if (hrgnUpdate > (HRGN)1) DeleteObject( hrgnUpdate );
 187         hrgnUpdate = 0;
 188         dcx_flags &= ~DCX_INTERSECTRGN;
 189     }
 190     else
 191     {
 192         if (!hrgnUpdate)  /* empty region, clip everything */
 193         {
 194             hrgnUpdate = CreateRectRgn( 0, 0, 0, 0 );
 195         }
 196         else if (hrgnUpdate == (HRGN)1)  /* whole client area, don't clip */
 197         {
 198             hrgnUpdate = 0;
 199             dcx_flags &= ~DCX_INTERSECTRGN;
 200         }
 201     }
 202     lps->hdc = GetDCEx( hwnd, hrgnUpdate, dcx_flags );
 203     /* ReleaseDC() in EndPaint() will delete the region */
 204
 205     if (!lps->hdc)
 206     {
 207         WARN("GetDCEx() failed in BeginPaint(), hwnd=%p\n", hwnd);
 208         DeleteObject( hrgnUpdate );
 209         return 0;
 210     }
 211
 212     /* It is possible that the clip box is bigger than the window itself,
 213        if CS_PARENTDC flag is set. Windows never return a paint rect bigger
 214        than the window itself, so we need to intersect the cliprect with
 215        the window  */
 216     GetClientRect( hwnd, &clientRect );
 217
 218     GetClipBox( lps->hdc, &clipRect );
 219     LPtoDP(lps->hdc, (LPPOINT)&clipRect, 2);      /* GetClipBox returns LP */
 220
 221     IntersectRect(&lps->rcPaint, &clientRect, &clipRect);
 222     DPtoLP(lps->hdc, (LPPOINT)&lps->rcPaint, 2);  /* we must return LP */
 223
 224     TRACE("hdc = %p box = (%ld,%ld - %ld,%ld)\n",
 225           lps->hdc, lps->rcPaint.left, lps->rcPaint.top, lps->rcPaint.right, lps->rcPaint.bottom );
 226
 227     if (!(wndPtr = WIN_GetPtr( hwnd )) || wndPtr == WND_OTHER_PROCESS) return 0;
 228     lps->fErase = !(wndPtr->flags & WIN_NEEDS_ERASEBKGND);
 229     wndPtr->flags &= ~WIN_NEEDS_ERASEBKGND;
 230     WIN_ReleasePtr( wndPtr );
 231
 232     if (!lps->fErase)
 233         lps->fErase = !SendMessageA( hwnd, bIcon ? WM_ICONERASEBKGND : WM_ERASEBKGND,
 234                                      (WPARAM)lps->hdc, 0 );
 235     return lps->hdc;
 236 }
 237
 238
 239 /***********************************************************************
 240  *              EndPaint (USER32.@)
 241  */
 242 BOOL WINAPI EndPaint( HWND hwnd, const PAINTSTRUCT *lps )
 243 {
 244     if (!lps) return FALSE;
 245
 246     ReleaseDC( hwnd, lps->hdc );
 247     ShowCaret( hwnd );
 248     return TRUE;
 249 }