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 <stdarg.h>
  22 #include <string.h>
  23
  24 #include "windef.h"
  25 #include "winbase.h"
  26 #include "wingdi.h"
  27 #include "wine/winuser16.h"
  28 #include "wine/server.h"
  29 #include "win.h"
  30 #include "dce.h"
  31 #include "wine/debug.h"
  32
  33 WINE_DEFAULT_DEBUG_CHANNEL(win);
  34
  35 /***********************************************************************
  36  *           add_paint_count
  37  *
  38  * Add an increment (normally 1 or -1) to the current paint count of a window.
  39  */
  40 static void add_paint_count( HWND hwnd, int incr )
  41 {
  42     SERVER_START_REQ( inc_window_paint_count )
  43     {
  44         req->handle = hwnd;
  45         req->incr   = incr;
  46         wine_server_call( req );
  47     }
  48     SERVER_END_REQ;
  49 }
  50
  51
  52 /***********************************************************************
  53  *           copy_rgn
  54  *
  55  * copy a region, doing the right thing if the source region is 0 or 1
  56  */
  57 static HRGN copy_rgn( HRGN hSrc )
  58 {
  59     if (hSrc > (HRGN)1)
  60     {
  61         HRGN hrgn = CreateRectRgn( 0, 0, 0, 0 );
  62         CombineRgn( hrgn, hSrc, 0, RGN_COPY );
  63         return hrgn;
  64     }
  65     return hSrc;
  66 }
  67
  68
  69 /***********************************************************************
  70  *           get_update_regions
  71  *
  72  * Return update regions for the whole window and for the client area.
  73  */
  74 static void get_update_regions( WND *win, HRGN *whole_rgn, HRGN *client_rgn )
  75 {
  76     if (win->hrgnUpdate > (HRGN)1)
  77     {
  78         RECT client, update;
  79
  80         /* check if update rgn overlaps with nonclient area */
  81         GetRgnBox( win->hrgnUpdate, &update );
  82         client = win->rectClient;
  83         OffsetRect( &client, -win->rectWindow.left, -win->rectWindow.top );
  84
  85         if (update.left < client.left || update.top < client.top ||
  86             update.right > client.right || update.bottom > client.bottom)
  87         {
  88             *whole_rgn = copy_rgn( win->hrgnUpdate );
  89             *client_rgn = CreateRectRgnIndirect( &client );
  90             if (CombineRgn( *client_rgn, *client_rgn, win->hrgnUpdate, RGN_AND ) == NULLREGION)
  91             {
  92                 DeleteObject( *client_rgn );
  93                 *client_rgn = 0;
  94             }
  95         }
  96         else
  97         {
  98             *whole_rgn = 0;
  99             *client_rgn = copy_rgn( win->hrgnUpdate );
 100         }
 101     }
 102     else
 103     {
 104         *client_rgn = *whole_rgn = win->hrgnUpdate;  /* 0 or 1 */
 105     }
 106 }
 107
 108
 109 /***********************************************************************
 110  *           begin_ncpaint
 111  *
 112  * Send a WM_NCPAINT message from inside BeginPaint().
 113  * Returns update region cropped to client rectangle (and in client coords),
 114  * and clears window update region and internal paint flag.
 115  */
 116 static HRGN begin_ncpaint( HWND hwnd )
 117 {
 118     HRGN whole_rgn, client_rgn;
 119     WND *wnd = WIN_GetPtr( hwnd );
 120
 121     if (!wnd || wnd == WND_OTHER_PROCESS) return 0;
 122
 123     TRACE("hwnd %p [%p] ncf %i\n",
 124           hwnd, wnd->hrgnUpdate, wnd->flags & WIN_NEEDS_NCPAINT);
 125
 126     get_update_regions( wnd, &whole_rgn, &client_rgn );
 127
 128     if (whole_rgn) /* NOTE: WM_NCPAINT allows wParam to be 1 */
 129     {
 130         WIN_ReleasePtr( wnd );
 131         SendMessageA( hwnd, WM_NCPAINT, (WPARAM)whole_rgn, 0 );
 132         if (whole_rgn > (HRGN)1) DeleteObject( whole_rgn );
 133         /* make sure the window still exists before continuing */
 134         if (!(wnd = WIN_GetPtr( hwnd )) || wnd == WND_OTHER_PROCESS)
 135         {
 136             if (client_rgn > (HRGN)1) DeleteObject( client_rgn );
 137             return 0;
 138         }
 139     }
 140
 141     if (wnd->hrgnUpdate || (wnd->flags & WIN_INTERNAL_PAINT)) add_paint_count( hwnd, -1 );
 142     if (wnd->hrgnUpdate > (HRGN)1) DeleteObject( wnd->hrgnUpdate );
 143     wnd->hrgnUpdate = 0;
 144     wnd->flags &= ~(WIN_INTERNAL_PAINT | WIN_NEEDS_NCPAINT | WIN_NEEDS_BEGINPAINT);
 145     if (client_rgn > (HRGN)1) OffsetRgn( client_rgn, wnd->rectWindow.left - wnd->rectClient.left,
 146                                          wnd->rectWindow.top - wnd->rectClient.top );
 147     WIN_ReleasePtr( wnd );
 148     return client_rgn;
 149 }
 150
 151
 152 /***********************************************************************
 153  *              BeginPaint (USER32.@)
 154  */
 155 HDC WINAPI BeginPaint( HWND hwnd, PAINTSTRUCT *lps )
 156 {
 157     INT dcx_flags;
 158     BOOL bIcon;
 159     HRGN hrgnUpdate;
 160     RECT clipRect, clientRect;
 161     HWND full_handle;
 162     WND *wndPtr;
 163
 164     if (!lps) return 0;
 165
 166     if (!(full_handle = WIN_IsCurrentThread( hwnd )))
 167     {
 168         if (IsWindow(hwnd))
 169             FIXME( "window %p belongs to other thread\n", hwnd );
 170         return 0;
 171     }
 172     hwnd = full_handle;
 173
 174     /* send WM_NCPAINT and retrieve update region */
 175     hrgnUpdate = begin_ncpaint( hwnd );
 176     if (!hrgnUpdate && !IsWindow( hwnd )) return 0;
 177
 178     HideCaret( hwnd );
 179
 180     bIcon = (IsIconic(hwnd) && GetClassLongA(hwnd, GCL_HICON));
 181
 182     dcx_flags = DCX_INTERSECTRGN | DCX_WINDOWPAINT | DCX_USESTYLE;
 183     if (bIcon) dcx_flags |= DCX_WINDOW;
 184
 185     if (GetClassLongA( hwnd, GCL_STYLE ) & CS_PARENTDC)
 186     {
 187         /* Don't clip the output to the update region for CS_PARENTDC window */
 188         if (hrgnUpdate > (HRGN)1) DeleteObject( hrgnUpdate );
 189         hrgnUpdate = 0;
 190         dcx_flags &= ~DCX_INTERSECTRGN;
 191     }
 192     else
 193     {
 194         if (!hrgnUpdate)  /* empty region, clip everything */
 195         {
 196             hrgnUpdate = CreateRectRgn( 0, 0, 0, 0 );
 197         }
 198         else if (hrgnUpdate == (HRGN)1)  /* whole client area, don't clip */
 199         {
 200             hrgnUpdate = 0;
 201             dcx_flags &= ~DCX_INTERSECTRGN;
 202         }
 203     }
 204     lps->hdc = GetDCEx( hwnd, hrgnUpdate, dcx_flags );
 205     /* ReleaseDC() in EndPaint() will delete the region */
 206
 207     if (!lps->hdc)
 208     {
 209         WARN("GetDCEx() failed in BeginPaint(), hwnd=%p\n", hwnd);
 210         DeleteObject( hrgnUpdate );
 211         return 0;
 212     }
 213
 214     /* It is possible that the clip box is bigger than the window itself,
 215        if CS_PARENTDC flag is set. Windows never return a paint rect bigger
 216        than the window itself, so we need to intersect the cliprect with
 217        the window  */
 218     GetClientRect( hwnd, &clientRect );
 219
 220     GetClipBox( lps->hdc, &clipRect );
 221     LPtoDP(lps->hdc, (LPPOINT)&clipRect, 2);      /* GetClipBox returns LP */
 222
 223     IntersectRect(&lps->rcPaint, &clientRect, &clipRect);
 224     DPtoLP(lps->hdc, (LPPOINT)&lps->rcPaint, 2);  /* we must return LP */
 225
 226     TRACE("hdc = %p box = (%ld,%ld - %ld,%ld)\n",
 227           lps->hdc, lps->rcPaint.left, lps->rcPaint.top, lps->rcPaint.right, lps->rcPaint.bottom );
 228
 229     if (!(wndPtr = WIN_GetPtr( hwnd )) || wndPtr == WND_OTHER_PROCESS) return 0;
 230     lps->fErase = (wndPtr->flags & WIN_NEEDS_ERASEBKGND) != 0;
 231     wndPtr->flags &= ~WIN_NEEDS_ERASEBKGND;
 232     WIN_ReleasePtr( wndPtr );
 233
 234     if (lps->fErase)
 235         lps->fErase = !SendMessageA( hwnd, bIcon ? WM_ICONERASEBKGND : WM_ERASEBKGND,
 236                                      (WPARAM)lps->hdc, 0 );
 237
 238     TRACE("hdc = %p box = (%ld,%ld - %ld,%ld), fErase = %d\n",
 239           lps->hdc, lps->rcPaint.left, lps->rcPaint.top, lps->rcPaint.right, lps->rcPaint.bottom,
 240           lps->fErase);
 241
 242     return lps->hdc;
 243 }
 244
 245
 246 /***********************************************************************
 247  *              EndPaint (USER32.@)
 248  */
 249 BOOL WINAPI EndPaint( HWND hwnd, const PAINTSTRUCT *lps )
 250 {
 251     if (!lps) return FALSE;
 252
 253     ReleaseDC( hwnd, lps->hdc );
 254     ShowCaret( hwnd );
 255     return TRUE;
 256 }