dlls/user32/painting.c

   1 /*
   2  * Window painting functions
   3  *
   4  * Copyright 1993, 1994, 1995, 2001, 2004, 2005, 2008 Alexandre Julliard
   5  * Copyright 1996, 1997, 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  20  */
  21
  22 #include "config.h"
  23 #include "wine/port.h"
  24
  25 #include <assert.h>
  26 #include <stdarg.h>
  27 #include <string.h>
  28
  29 #include "ntstatus.h"
  30 #define WIN32_NO_STATUS
  31 #include "windef.h"
  32 #include "winbase.h"
  33 #include "wingdi.h"
  34 #include "winuser.h"
  35 #include "wine/server.h"
  36 #include "win.h"
  37 #include "user_private.h"
  38 #include "controls.h"
  39 #include "wine/list.h"
  40 #include "wine/debug.h"
  41
  42 WINE_DEFAULT_DEBUG_CHANNEL(win);
  43
  44
  45 struct dce
  46 {
  47     struct list entry;         /* entry in global DCE list */
  48     HDC         hdc;
  49     HWND        hwnd;
  50     HRGN        clip_rgn;
  51     DWORD       flags;
  52     LONG        count;         /* usage count; 0 or 1 for cache DCEs, always 1 for window DCEs,
  53                                   always >= 1 for class DCEs */
  54 };
  55
  56 static struct list dce_list = LIST_INIT(dce_list);
  57
  58 static BOOL CALLBACK dc_hook( HDC hDC, WORD code, DWORD_PTR data, LPARAM lParam );
  59
  60 static const WCHAR displayW[] = { 'D','I','S','P','L','A','Y',0 };
  61
  62
  63 /***********************************************************************
  64  *           dump_rdw_flags
  65  */
  66 static void dump_rdw_flags(UINT flags)
  67 {
  68     TRACE("flags:");
  69     if (flags & RDW_INVALIDATE) TRACE(" RDW_INVALIDATE");
  70     if (flags & RDW_INTERNALPAINT) TRACE(" RDW_INTERNALPAINT");
  71     if (flags & RDW_ERASE) TRACE(" RDW_ERASE");
  72     if (flags & RDW_VALIDATE) TRACE(" RDW_VALIDATE");
  73     if (flags & RDW_NOINTERNALPAINT) TRACE(" RDW_NOINTERNALPAINT");
  74     if (flags & RDW_NOERASE) TRACE(" RDW_NOERASE");
  75     if (flags & RDW_NOCHILDREN) TRACE(" RDW_NOCHILDREN");
  76     if (flags & RDW_ALLCHILDREN) TRACE(" RDW_ALLCHILDREN");
  77     if (flags & RDW_UPDATENOW) TRACE(" RDW_UPDATENOW");
  78     if (flags & RDW_ERASENOW) TRACE(" RDW_ERASENOW");
  79     if (flags & RDW_FRAME) TRACE(" RDW_FRAME");
  80     if (flags & RDW_NOFRAME) TRACE(" RDW_NOFRAME");
  81
  82 #define RDW_FLAGS \
  83     (RDW_INVALIDATE | \
  84     RDW_INTERNALPAINT | \
  85     RDW_ERASE | \
  86     RDW_VALIDATE | \
  87     RDW_NOINTERNALPAINT | \
  88     RDW_NOERASE | \
  89     RDW_NOCHILDREN | \
  90     RDW_ALLCHILDREN | \
  91     RDW_UPDATENOW | \
  92     RDW_ERASENOW | \
  93     RDW_FRAME | \
  94     RDW_NOFRAME)
  95
  96     if (flags & ~RDW_FLAGS) TRACE(" %04x", flags & ~RDW_FLAGS);
  97     TRACE("\n");
  98 #undef RDW_FLAGS
  99 }
 100
 101
 102 /***********************************************************************
 103  *              update_visible_region
 104  *
 105  * Set the visible region and X11 drawable for the DC associated to
 106  * a given window.
 107  */
 108 static void update_visible_region( struct dce *dce )
 109 {
 110     NTSTATUS status;
 111     HRGN vis_rgn = 0;
 112     HWND top_win = 0;
 113     DWORD flags = dce->flags;
 114     size_t size = 256;
 115     RECT win_rect, top_rect;
 116
 117     /* don't clip siblings if using parent clip region */
 118     if (flags & DCX_PARENTCLIP) flags &= ~DCX_CLIPSIBLINGS;
 119
 120     /* fetch the visible region from the server */
 121     do
 122     {
 123         RGNDATA *data = HeapAlloc( GetProcessHeap(), 0, sizeof(*data) + size - 1 );
 124         if (!data) return;
 125
 126         SERVER_START_REQ( get_visible_region )
 127         {
 128             req->window  = wine_server_user_handle( dce->hwnd );
 129             req->flags   = flags;
 130             wine_server_set_reply( req, data->Buffer, size );
 131             if (!(status = wine_server_call( req )))
 132             {
 133                 size_t reply_size = wine_server_reply_size( reply );
 134                 data->rdh.dwSize   = sizeof(data->rdh);
 135                 data->rdh.iType    = RDH_RECTANGLES;
 136                 data->rdh.nCount   = reply_size / sizeof(RECT);
 137                 data->rdh.nRgnSize = reply_size;
 138                 vis_rgn = ExtCreateRegion( NULL, size, data );
 139
 140                 top_win         = wine_server_ptr_handle( reply->top_win );
 141                 win_rect.left   = reply->win_rect.left;
 142                 win_rect.top    = reply->win_rect.top;
 143                 win_rect.right  = reply->win_rect.right;
 144                 win_rect.bottom = reply->win_rect.bottom;
 145                 top_rect.left   = reply->top_rect.left;
 146                 top_rect.top    = reply->top_rect.top;
 147                 top_rect.right  = reply->top_rect.right;
 148                 top_rect.bottom = reply->top_rect.bottom;
 149             }
 150             else size = reply->total_size;
 151         }
 152         SERVER_END_REQ;
 153         HeapFree( GetProcessHeap(), 0, data );
 154     } while (status == STATUS_BUFFER_OVERFLOW);
 155
 156     if (status || !vis_rgn) return;
 157
 158     USER_Driver->pGetDC( dce->hdc, dce->hwnd, top_win, &win_rect, &top_rect, flags );
 159
 160     if (dce->clip_rgn) CombineRgn( vis_rgn, vis_rgn, dce->clip_rgn,
 161                                    (flags & DCX_INTERSECTRGN) ? RGN_AND : RGN_DIFF );
 162
 163     /* map region to DC coordinates */
 164     OffsetRgn( vis_rgn, -win_rect.left, -win_rect.top );
 165     SelectVisRgn( dce->hdc, vis_rgn );
 166     DeleteObject( vis_rgn );
 167 }
 168
 169
 170 /***********************************************************************
 171  *              reset_dce_attrs
 172  */
 173 static void reset_dce_attrs( struct dce *dce )
 174 {
 175     RestoreDC( dce->hdc, 1 );  /* initial save level is always 1 */
 176     SaveDC( dce->hdc );  /* save the state again for next time */
 177 }
 178
 179
 180 /***********************************************************************
 181  *              release_dce
 182  */
 183 static void release_dce( struct dce *dce )
 184 {
 185     if (!dce->hwnd) return;  /* already released */
 186
 187     USER_Driver->pReleaseDC( dce->hwnd, dce->hdc );
 188
 189     if (dce->clip_rgn) DeleteObject( dce->clip_rgn );
 190     dce->clip_rgn = 0;
 191     dce->hwnd     = 0;
 192     dce->flags   &= DCX_CACHE;
 193 }
 194
 195
 196 /***********************************************************************
 197  *   delete_clip_rgn
 198  */
 199 static void delete_clip_rgn( struct dce *dce )
 200 {
 201     if (!dce->clip_rgn) return;  /* nothing to do */
 202
 203     dce->flags &= ~(DCX_EXCLUDERGN | DCX_INTERSECTRGN);
 204     DeleteObject( dce->clip_rgn );
 205     dce->clip_rgn = 0;
 206
 207     /* make it dirty so that the vis rgn gets recomputed next time */
 208     SetHookFlags( dce->hdc, DCHF_INVALIDATEVISRGN );
 209 }
 210
 211
 212 /***********************************************************************
 213  *           alloc_dce
 214  *
 215  * Allocate a new DCE.
 216  */
 217 static struct dce *alloc_dce(void)
 218 {
 219     struct dce *dce;
 220
 221     if (!(dce = HeapAlloc( GetProcessHeap(), 0, sizeof(*dce) ))) return NULL;
 222     if (!(dce->hdc = CreateDCW( displayW, NULL, NULL, NULL )))
 223     {
 224         HeapFree( GetProcessHeap(), 0, dce );
 225         return 0;
 226     }
 227     SaveDC( dce->hdc );
 228
 229     dce->hwnd      = 0;
 230     dce->clip_rgn  = 0;
 231     dce->flags     = 0;
 232     dce->count     = 1;
 233
 234     /* store DCE handle in DC hook data field */
 235     SetDCHook( dce->hdc, dc_hook, (DWORD_PTR)dce );
 236     SetHookFlags( dce->hdc, DCHF_INVALIDATEVISRGN );
 237     return dce;
 238 }
 239
 240
 241 /***********************************************************************
 242  *              get_window_dce
 243  */
 244 static struct dce *get_window_dce( HWND hwnd )
 245 {
 246     struct dce *dce;
 247     WND *win = WIN_GetPtr( hwnd );
 248
 249     if (!win || win == WND_OTHER_PROCESS || win == WND_DESKTOP) return NULL;
 250
 251     dce = win->dce;
 252     if (!dce && (dce = get_class_dce( win->class )))
 253     {
 254         win->dce = dce;
 255         dce->count++;
 256     }
 257     WIN_ReleasePtr( win );
 258
 259     if (!dce)  /* try to allocate one */
 260     {
 261         struct dce *dce_to_free = NULL;
 262         LONG class_style = GetClassLongW( hwnd, GCL_STYLE );
 263
 264         if (class_style & CS_CLASSDC)
 265         {
 266             if (!(dce = alloc_dce())) return NULL;
 267
 268             win = WIN_GetPtr( hwnd );
 269             if (win && win != WND_OTHER_PROCESS && win != WND_DESKTOP)
 270             {
 271                 if (win->dce)  /* another thread beat us to it */
 272                 {
 273                     dce_to_free = dce;
 274                     dce = win->dce;
 275                 }
 276                 else if ((win->dce = set_class_dce( win->class, dce )) != dce)
 277                 {
 278                     dce_to_free = dce;
 279                     dce = win->dce;
 280                     dce->count++;
 281                 }
 282                 else
 283                 {
 284                     dce->count++;
 285                     list_add_tail( &dce_list, &dce->entry );
 286                 }
 287                 WIN_ReleasePtr( win );
 288             }
 289             else dce_to_free = dce;
 290         }
 291         else if (class_style & CS_OWNDC)
 292         {
 293             if (!(dce = alloc_dce())) return NULL;
 294
 295             win = WIN_GetPtr( hwnd );
 296             if (win && win != WND_OTHER_PROCESS && win != WND_DESKTOP)
 297             {
 298                 if (win->dwStyle & WS_CLIPCHILDREN) dce->flags |= DCX_CLIPCHILDREN;
 299                 if (win->dwStyle & WS_CLIPSIBLINGS) dce->flags |= DCX_CLIPSIBLINGS;
 300                 if (win->dce)  /* another thread beat us to it */
 301                 {
 302                     dce_to_free = dce;
 303                     dce = win->dce;
 304                 }
 305                 else
 306                 {
 307                     win->dce = dce;
 308                     dce->hwnd = hwnd;
 309                     dce->count++;
 310                     list_add_tail( &dce_list, &dce->entry );
 311                 }
 312                 WIN_ReleasePtr( win );
 313             }
 314             else dce_to_free = dce;
 315         }
 316
 317         if (dce_to_free)
 318         {
 319             SetDCHook( dce->hdc, NULL, 0 );
 320             DeleteDC( dce->hdc );
 321             HeapFree( GetProcessHeap(), 0, dce );
 322         }
 323     }
 324     return dce;
 325 }
 326
 327
 328 /***********************************************************************
 329  *           free_dce
 330  *
 331  * Free a class or window DCE.
 332  */
 333 void free_dce( struct dce *dce, HWND hwnd )
 334 {
 335     USER_Lock();
 336
 337     if (dce)
 338     {
 339         if (!--dce->count)
 340         {
 341             /* turn it into a cache entry */
 342             reset_dce_attrs( dce );
 343             release_dce( dce );
 344             dce->flags |= DCX_CACHE;
 345         }
 346         else if (dce->hwnd == hwnd)
 347         {
 348             release_dce( dce );
 349         }
 350     }
 351
 352     /* now check for cache DCEs */
 353
 354     if (hwnd)
 355     {
 356         LIST_FOR_EACH_ENTRY( dce, &dce_list, struct dce, entry )
 357         {
 358             if (dce->hwnd != hwnd) continue;
 359             if (!(dce->flags & DCX_CACHE)) continue;
 360
 361             if (dce->count) WARN( "GetDC() without ReleaseDC() for window %p\n", hwnd );
 362             dce->count = 0;
 363             release_dce( dce );
 364         }
 365     }
 366
 367     USER_Unlock();
 368 }
 369
 370
 371 /***********************************************************************
 372  *           make_dc_dirty
 373  *
 374  * Mark the associated DC as dirty to force a refresh of the visible region
 375  */
 376 static void make_dc_dirty( struct dce *dce )
 377 {
 378     if (!dce->count)
 379     {
 380         /* Don't bother with visible regions of unused DCEs */
 381         TRACE("\tpurged %p dce [%p]\n", dce, dce->hwnd);
 382         release_dce( dce );
 383     }
 384     else
 385     {
 386         /* Set dirty bits in the hDC and DCE structs */
 387         TRACE("\tfixed up %p dce [%p]\n", dce, dce->hwnd);
 388         SetHookFlags( dce->hdc, DCHF_INVALIDATEVISRGN );
 389     }
 390 }
 391
 392
 393 /***********************************************************************
 394  *   invalidate_dce
 395  *
 396  * It is called from SetWindowPos() - we have to
 397  * mark as dirty all busy DCEs for windows that have pWnd->parent as
 398  * an ancestor and whose client rect intersects with specified update
 399  * rectangle. In addition, pWnd->parent DCEs may need to be updated if
 400  * DCX_CLIPCHILDREN flag is set.
 401  */
 402 void invalidate_dce( HWND hwnd, const RECT *rect )
 403 {
 404     RECT window_rect, extra_rect;
 405     struct dce *dce;
 406     HWND hwndScope = GetAncestor( hwnd, GA_PARENT );
 407
 408     if (!hwndScope) return;
 409
 410     GetWindowRect( hwnd, &window_rect );
 411     if (rect)
 412     {
 413         extra_rect = *rect;
 414         MapWindowPoints( hwndScope, 0, (POINT *)&extra_rect, 2 );
 415     }
 416
 417     TRACE("%p scope hwnd = %p %s (%s)\n",
 418           hwnd, hwndScope, wine_dbgstr_rect(&window_rect), wine_dbgstr_rect(rect) );
 419
 420     /* walk all DCEs and fixup non-empty entries */
 421
 422     USER_Lock();
 423     LIST_FOR_EACH_ENTRY( dce, &dce_list, struct dce, entry )
 424     {
 425         TRACE( "%p: hwnd %p dcx %08x %s %s\n", dce, dce->hwnd, dce->flags,
 426                (dce->flags & DCX_CACHE) ? "Cache" : "Owned", dce->count ? "InUse" : "" );
 427
 428         if (!dce->hwnd) continue;
 429         if ((dce->hwnd == hwndScope) && !(dce->flags & DCX_CLIPCHILDREN))
 430             continue;  /* child window positions don't bother us */
 431
 432         /* if DCE window is a child of hwnd, it has to be invalidated */
 433         if (dce->hwnd == hwnd || IsChild( hwnd, dce->hwnd ))
 434         {
 435             make_dc_dirty( dce );
 436         }
 437         else  /* otherwise check if the window rectangle intersects this DCE window */
 438         {
 439             if (hwndScope == GetDesktopWindow() ||
 440                 hwndScope == dce->hwnd || IsChild( hwndScope, dce->hwnd ))
 441             {
 442                 RECT dce_rect, tmp;
 443                 GetWindowRect( dce->hwnd, &dce_rect );
 444                 if (IntersectRect( &tmp, &dce_rect, &window_rect ) ||
 445                     (rect && IntersectRect( &tmp, &dce_rect, &extra_rect )))
 446                     make_dc_dirty( dce );
 447             }
 448         }
 449     }
 450     USER_Unlock();
 451 }
 452
 453 /***********************************************************************
 454  *              release_dc
 455  *
 456  * Implementation of ReleaseDC.
 457  */
 458 static INT release_dc( HWND hwnd, HDC hdc, BOOL end_paint )
 459 {
 460     struct dce *dce;
 461     BOOL ret = FALSE;
 462
 463     TRACE("%p %p\n", hwnd, hdc );
 464
 465     USER_Lock();
 466     dce = (struct dce *)GetDCHook( hdc, NULL );
 467     if (dce && dce->count)
 468     {
 469         if (!(dce->flags & DCX_NORESETATTRS)) reset_dce_attrs( dce );
 470         if (end_paint || (dce->flags & DCX_CACHE)) delete_clip_rgn( dce );
 471         if (dce->flags & DCX_CACHE) dce->count = 0;
 472         ret = TRUE;
 473     }
 474     USER_Unlock();
 475     return ret;
 476 }
 477
 478
 479 /***********************************************************************
 480  *              dc_hook
 481  *
 482  * See "Undoc. Windows" for hints (DC, SetDCHook, SetHookFlags)..
 483  */
 484 static BOOL CALLBACK dc_hook( HDC hDC, WORD code, DWORD_PTR data, LPARAM lParam )
 485 {
 486     BOOL retv = TRUE;
 487     struct dce *dce = (struct dce *)data;
 488
 489     TRACE("hDC = %p, %u\n", hDC, code);
 490
 491     if (!dce) return 0;
 492     assert( dce->hdc == hDC );
 493
 494     switch( code )
 495     {
 496     case DCHC_INVALIDVISRGN:
 497         /* GDI code calls this when it detects that the
 498          * DC is dirty (usually after SetHookFlags()). This
 499          * means that we have to recompute the visible region.
 500          */
 501         if (dce->count) update_visible_region( dce );
 502         else /* non-fatal but shouldn't happen */
 503             WARN("DC is not in use!\n");
 504         break;
 505     case DCHC_DELETEDC:
 506         /*
 507          * Windows will not let you delete a DC that is busy
 508          * (between GetDC and ReleaseDC)
 509          */
 510         USER_Lock();
 511         if (dce->count > 1)
 512         {
 513             WARN("Application trying to delete a busy DC %p\n", dce->hdc);
 514             retv = FALSE;
 515         }
 516         else
 517         {
 518             list_remove( &dce->entry );
 519             if (dce->clip_rgn) DeleteObject( dce->clip_rgn );
 520             HeapFree( GetProcessHeap(), 0, dce );
 521         }
 522         USER_Unlock();
 523         break;
 524     }
 525     return retv;
 526 }
 527
 528
 529 /***********************************************************************
 530  *           get_update_region
 531  *
 532  * Return update region (in screen coordinates) for a window.
 533  */
 534 static HRGN get_update_region( HWND hwnd, UINT *flags, HWND *child )
 535 {
 536     HRGN hrgn = 0;
 537     NTSTATUS status;
 538     RGNDATA *data;
 539     size_t size = 256;
 540
 541     do
 542     {
 543         if (!(data = HeapAlloc( GetProcessHeap(), 0, sizeof(*data) + size - 1 )))
 544         {
 545             SetLastError( ERROR_OUTOFMEMORY );
 546             return 0;
 547         }
 548
 549         SERVER_START_REQ( get_update_region )
 550         {
 551             req->window     = wine_server_user_handle( hwnd );
 552             req->from_child = wine_server_user_handle( child ? *child : 0 );
 553             req->flags      = *flags;
 554             wine_server_set_reply( req, data->Buffer, size );
 555             if (!(status = wine_server_call( req )))
 556             {
 557                 size_t reply_size = wine_server_reply_size( reply );
 558                 data->rdh.dwSize   = sizeof(data->rdh);
 559                 data->rdh.iType    = RDH_RECTANGLES;
 560                 data->rdh.nCount   = reply_size / sizeof(RECT);
 561                 data->rdh.nRgnSize = reply_size;
 562                 hrgn = ExtCreateRegion( NULL, size, data );
 563                 if (child) *child = wine_server_ptr_handle( reply->child );
 564                 *flags = reply->flags;
 565             }
 566             else size = reply->total_size;
 567         }
 568         SERVER_END_REQ;
 569         HeapFree( GetProcessHeap(), 0, data );
 570     } while (status == STATUS_BUFFER_OVERFLOW);
 571
 572     if (status) SetLastError( RtlNtStatusToDosError(status) );
 573     return hrgn;
 574 }
 575
 576
 577 /***********************************************************************
 578  *           get_update_flags
 579  *
 580  * Get only the update flags, not the update region.
 581  */
 582 static BOOL get_update_flags( HWND hwnd, HWND *child, UINT *flags )
 583 {
 584     BOOL ret;
 585
 586     SERVER_START_REQ( get_update_region )
 587     {
 588         req->window     = wine_server_user_handle( hwnd );
 589         req->from_child = wine_server_user_handle( child ? *child : 0 );
 590         req->flags      = *flags | UPDATE_NOREGION;
 591         if ((ret = !wine_server_call_err( req )))
 592         {
 593             if (child) *child = wine_server_ptr_handle( reply->child );
 594             *flags = reply->flags;
 595         }
 596     }
 597     SERVER_END_REQ;
 598     return ret;
 599 }
 600
 601
 602 /***********************************************************************
 603  *           redraw_window_rects
 604  *
 605  * Redraw part of a window.
 606  */
 607 static BOOL redraw_window_rects( HWND hwnd, UINT flags, const RECT *rects, UINT count )
 608 {
 609     BOOL ret;
 610
 611     if (!(flags & (RDW_INVALIDATE|RDW_VALIDATE|RDW_INTERNALPAINT|RDW_NOINTERNALPAINT)))
 612         return TRUE;  /* nothing to do */
 613
 614     SERVER_START_REQ( redraw_window )
 615     {
 616         req->window = wine_server_user_handle( hwnd );
 617         req->flags  = flags;
 618         wine_server_add_data( req, rects, count * sizeof(RECT) );
 619         ret = !wine_server_call_err( req );
 620     }
 621     SERVER_END_REQ;
 622     return ret;
 623 }
 624
 625
 626 /***********************************************************************
 627  *           send_ncpaint
 628  *
 629  * Send a WM_NCPAINT message if needed, and return the resulting update region (in screen coords).
 630  * Helper for erase_now and BeginPaint.
 631  */
 632 static HRGN send_ncpaint( HWND hwnd, HWND *child, UINT *flags )
 633 {
 634     HRGN whole_rgn = get_update_region( hwnd, flags, child );
 635     HRGN client_rgn = 0;
 636
 637     if (child) hwnd = *child;
 638
 639     if (hwnd == GetDesktopWindow()) return whole_rgn;
 640
 641     if (whole_rgn)
 642     {
 643         RECT client, update;
 644         INT type;
 645
 646         /* check if update rgn overlaps with nonclient area */
 647         type = GetRgnBox( whole_rgn, &update );
 648         GetClientRect( hwnd, &client );
 649         MapWindowPoints( hwnd, 0, (POINT *)&client, 2 );
 650
 651         if ((*flags & UPDATE_NONCLIENT) ||
 652             update.left < client.left || update.top < client.top ||
 653             update.right > client.right || update.bottom > client.bottom)
 654         {
 655             client_rgn = CreateRectRgnIndirect( &client );
 656             CombineRgn( client_rgn, client_rgn, whole_rgn, RGN_AND );
 657
 658             /* check if update rgn contains complete nonclient area */
 659             if (type == SIMPLEREGION)
 660             {
 661                 RECT window;
 662                 GetWindowRect( hwnd, &window );
 663                 if (EqualRect( &window, &update ))
 664                 {
 665                     DeleteObject( whole_rgn );
 666                     whole_rgn = (HRGN)1;
 667                 }
 668             }
 669         }
 670         else
 671         {
 672             client_rgn = whole_rgn;
 673             whole_rgn = 0;
 674         }
 675
 676         if (whole_rgn) /* NOTE: WM_NCPAINT allows wParam to be 1 */
 677         {
 678             if (*flags & UPDATE_NONCLIENT) SendMessageW( hwnd, WM_NCPAINT, (WPARAM)whole_rgn, 0 );
 679             if (whole_rgn > (HRGN)1) DeleteObject( whole_rgn );
 680         }
 681     }
 682     return client_rgn;
 683 }
 684
 685
 686 /***********************************************************************
 687  *           send_erase
 688  *
 689  * Send a WM_ERASEBKGND message if needed, and optionally return the DC for painting.
 690  * If a DC is requested, the region is selected into it. In all cases the region is deleted.
 691  * Helper for erase_now and BeginPaint.
 692  */
 693 static BOOL send_erase( HWND hwnd, UINT flags, HRGN client_rgn,
 694                         RECT *clip_rect, HDC *hdc_ret )
 695 {
 696     BOOL need_erase = (flags & UPDATE_DELAYED_ERASE) != 0;
 697     HDC hdc = 0;
 698     RECT dummy;
 699
 700     if (!clip_rect) clip_rect = &dummy;
 701     if (hdc_ret || (flags & UPDATE_ERASE))
 702     {
 703         UINT dcx_flags = DCX_INTERSECTRGN | DCX_USESTYLE;
 704         if (IsIconic(hwnd)) dcx_flags |= DCX_WINDOW;
 705
 706         if ((hdc = GetDCEx( hwnd, client_rgn, dcx_flags )))
 707         {
 708             INT type = GetClipBox( hdc, clip_rect );
 709
 710             if (flags & UPDATE_ERASE)
 711             {
 712                 /* don't erase if the clip box is empty */
 713                 if (type != NULLREGION)
 714                     need_erase = !SendMessageW( hwnd, WM_ERASEBKGND, (WPARAM)hdc, 0 );
 715             }
 716             if (!hdc_ret) release_dc( hwnd, hdc, TRUE );
 717         }
 718
 719         if (hdc_ret) *hdc_ret = hdc;
 720     }
 721     if (!hdc) DeleteObject( client_rgn );
 722     return need_erase;
 723 }
 724
 725
 726 /***********************************************************************
 727  *           erase_now
 728  *
 729  * Implementation of RDW_ERASENOW behavior.
 730  */
 731 void erase_now( HWND hwnd, UINT rdw_flags )
 732 {
 733     HWND child = 0;
 734     HRGN hrgn;
 735     BOOL need_erase = FALSE;
 736
 737     /* loop while we find a child to repaint */
 738     for (;;)
 739     {
 740         UINT flags = UPDATE_NONCLIENT | UPDATE_ERASE;
 741
 742         if (rdw_flags & RDW_NOCHILDREN) flags |= UPDATE_NOCHILDREN;
 743         else if (rdw_flags & RDW_ALLCHILDREN) flags |= UPDATE_ALLCHILDREN;
 744         if (need_erase) flags |= UPDATE_DELAYED_ERASE;
 745
 746         if (!(hrgn = send_ncpaint( hwnd, &child, &flags ))) break;
 747         need_erase = send_erase( child, flags, hrgn, NULL, NULL );
 748
 749         if (!flags) break;  /* nothing more to do */
 750         if ((rdw_flags & RDW_NOCHILDREN) && !need_erase) break;
 751     }
 752 }
 753
 754
 755 /***********************************************************************
 756  *           update_now
 757  *
 758  * Implementation of RDW_UPDATENOW behavior.
 759  *
 760  * FIXME: Windows uses WM_SYNCPAINT to cut down the number of intertask
 761  * SendMessage() calls. This is a comment inside DefWindowProc() source
 762  * from 16-bit SDK:
 763  *
 764  *   This message avoids lots of inter-app message traffic
 765  *   by switching to the other task and continuing the
 766  *   recursion there.
 767  *
 768  * wParam         = flags
 769  * LOWORD(lParam) = hrgnClip
 770  * HIWORD(lParam) = hwndSkip  (not used; always NULL)
 771  *
 772  */
 773 static void update_now( HWND hwnd, UINT rdw_flags )
 774 {
 775     HWND child = 0;
 776
 777     /* desktop window never gets WM_PAINT, only WM_ERASEBKGND */
 778     if (hwnd == GetDesktopWindow()) erase_now( hwnd, rdw_flags | RDW_NOCHILDREN );
 779
 780     /* loop while we find a child to repaint */
 781     for (;;)
 782     {
 783         UINT flags = UPDATE_PAINT | UPDATE_INTERNALPAINT;
 784
 785         if (rdw_flags & RDW_NOCHILDREN) flags |= UPDATE_NOCHILDREN;
 786         else if (rdw_flags & RDW_ALLCHILDREN) flags |= UPDATE_ALLCHILDREN;
 787
 788         if (!get_update_flags( hwnd, &child, &flags )) break;
 789         if (!flags) break;  /* nothing more to do */
 790
 791         SendMessageW( child, WM_PAINT, 0, 0 );
 792         if (rdw_flags & RDW_NOCHILDREN) break;
 793     }
 794 }
 795
 796
 797 /*************************************************************************
 798  *             fix_caret
 799  *
 800  * Helper for ScrollWindowEx:
 801  * If the return value is 0, no special caret handling is necessary.
 802  * Otherwise the return value is the handle of the window that owns the
 803  * caret. Its caret needs to be hidden during the scroll operation and
 804  * moved to new_caret_pos if move_caret is TRUE.
 805  */
 806 static HWND fix_caret(HWND hWnd, const RECT *scroll_rect, INT dx, INT dy,
 807                      UINT flags, LPBOOL move_caret, LPPOINT new_caret_pos)
 808 {
 809     GUITHREADINFO info;
 810     RECT rect, mapped_rcCaret;
 811     BOOL hide_caret = FALSE;
 812
 813     if (!GetGUIThreadInfo( GetCurrentThreadId(), &info )) return 0;
 814     if (!info.hwndCaret) return 0;
 815
 816     if (info.hwndCaret == hWnd)
 817     {
 818         /* Move the caret if it's (partially) in the source rectangle */
 819         if (IntersectRect(&rect, scroll_rect, &info.rcCaret))
 820         {
 821             *move_caret = TRUE;
 822             hide_caret = TRUE;
 823             new_caret_pos->x = info.rcCaret.left + dx;
 824             new_caret_pos->y = info.rcCaret.top + dy;
 825         }
 826         else
 827         {
 828             *move_caret = FALSE;
 829
 830             /* Hide the caret if it's in the destination rectangle */
 831             rect = *scroll_rect;
 832             OffsetRect(&rect, dx, dy);
 833             hide_caret = IntersectRect(&rect, &rect, &info.rcCaret);
 834         }
 835     }
 836     else
 837     {
 838         if ((flags & SW_SCROLLCHILDREN) && IsChild(hWnd, info.hwndCaret))
 839         {
 840             *move_caret = FALSE;
 841
 842             /* Hide the caret if it's in the source or in the destination
 843                rectangle */
 844             mapped_rcCaret = info.rcCaret;
 845             MapWindowPoints(info.hwndCaret, hWnd, (LPPOINT)&mapped_rcCaret, 2);
 846
 847             if (IntersectRect(&rect, scroll_rect, &mapped_rcCaret))
 848             {
 849                 hide_caret = TRUE;
 850             }
 851             else
 852             {
 853                 rect = *scroll_rect;
 854                 OffsetRect(&rect, dx, dy);
 855                 hide_caret = IntersectRect(&rect, &rect, &mapped_rcCaret);
 856             }
 857         }
 858         else
 859             return 0;
 860     }
 861
 862     if (hide_caret)
 863     {
 864         HideCaret(info.hwndCaret);
 865         return info.hwndCaret;
 866     }
 867     else
 868         return 0;
 869 }
 870
 871
 872 /***********************************************************************
 873  *              BeginPaint (USER32.@)
 874  */
 875 HDC WINAPI BeginPaint( HWND hwnd, PAINTSTRUCT *lps )
 876 {
 877     HRGN hrgn;
 878     UINT flags = UPDATE_NONCLIENT | UPDATE_ERASE | UPDATE_PAINT | UPDATE_INTERNALPAINT | UPDATE_NOCHILDREN;
 879
 880     if (!lps) return 0;
 881
 882     HideCaret( hwnd );
 883
 884     if (!(hrgn = send_ncpaint( hwnd, NULL, &flags ))) return 0;
 885
 886     lps->fErase = send_erase( hwnd, flags, hrgn, &lps->rcPaint, &lps->hdc );
 887
 888     TRACE("hdc = %p box = (%s), fErase = %d\n",
 889           lps->hdc, wine_dbgstr_rect(&lps->rcPaint), lps->fErase);
 890
 891     return lps->hdc;
 892 }
 893
 894
 895 /***********************************************************************
 896  *              EndPaint (USER32.@)
 897  */
 898 BOOL WINAPI EndPaint( HWND hwnd, const PAINTSTRUCT *lps )
 899 {
 900     if (!lps) return FALSE;
 901     release_dc( hwnd, lps->hdc, TRUE );
 902     ShowCaret( hwnd );
 903     return TRUE;
 904 }
 905
 906
 907 /***********************************************************************
 908  *              GetDCEx (USER32.@)
 909  */
 910 HDC WINAPI GetDCEx( HWND hwnd, HRGN hrgnClip, DWORD flags )
 911 {
 912     static const DWORD clip_flags = DCX_PARENTCLIP | DCX_CLIPSIBLINGS | DCX_CLIPCHILDREN | DCX_WINDOW;
 913     static const DWORD user_flags = clip_flags | DCX_NORESETATTRS; /* flags that can be set by user */
 914     struct dce *dce;
 915     BOOL bUpdateVisRgn = TRUE;
 916     HWND parent;
 917     LONG window_style = GetWindowLongW( hwnd, GWL_STYLE );
 918
 919     if (!hwnd) hwnd = GetDesktopWindow();
 920     else hwnd = WIN_GetFullHandle( hwnd );
 921
 922     TRACE("hwnd %p, hrgnClip %p, flags %08x\n", hwnd, hrgnClip, flags);
 923
 924     if (!IsWindow(hwnd)) return 0;
 925
 926     /* fixup flags */
 927
 928     if (flags & (DCX_WINDOW | DCX_PARENTCLIP)) flags |= DCX_CACHE;
 929
 930     if (flags & DCX_USESTYLE)
 931     {
 932         flags &= ~(DCX_CLIPCHILDREN | DCX_CLIPSIBLINGS | DCX_PARENTCLIP);
 933
 934         if (window_style & WS_CLIPSIBLINGS) flags |= DCX_CLIPSIBLINGS;
 935
 936         if (!(flags & DCX_WINDOW))
 937         {
 938             if (GetClassLongW( hwnd, GCL_STYLE ) & CS_PARENTDC) flags |= DCX_PARENTCLIP;
 939
 940             if (window_style & WS_CLIPCHILDREN && !(window_style & WS_MINIMIZE))
 941                 flags |= DCX_CLIPCHILDREN;
 942         }
 943     }
 944
 945     if (flags & DCX_WINDOW) flags &= ~DCX_CLIPCHILDREN;
 946
 947     parent = GetAncestor( hwnd, GA_PARENT );
 948     if (!parent || (parent == GetDesktopWindow()))
 949         flags = (flags & ~DCX_PARENTCLIP) | DCX_CLIPSIBLINGS;
 950
 951     /* it seems parent clip is ignored when clipping siblings or children */
 952     if (flags & (DCX_CLIPSIBLINGS | DCX_CLIPCHILDREN)) flags &= ~DCX_PARENTCLIP;
 953
 954     if( flags & DCX_PARENTCLIP )
 955     {
 956         LONG parent_style = GetWindowLongW( parent, GWL_STYLE );
 957         if( (window_style & WS_VISIBLE) && (parent_style & WS_VISIBLE) )
 958         {
 959             flags &= ~DCX_CLIPCHILDREN;
 960             if (parent_style & WS_CLIPSIBLINGS) flags |= DCX_CLIPSIBLINGS;
 961         }
 962     }
 963
 964     /* find a suitable DCE */
 965
 966     if ((flags & DCX_CACHE) || !(dce = get_window_dce( hwnd )))
 967     {
 968         struct dce *dceEmpty = NULL, *dceUnused = NULL;
 969
 970         /* Strategy: First, we attempt to find a non-empty but unused DCE with
 971          * compatible flags. Next, we look for an empty entry. If the cache is
 972          * full we have to purge one of the unused entries.
 973          */
 974         USER_Lock();
 975         LIST_FOR_EACH_ENTRY( dce, &dce_list, struct dce, entry )
 976         {
 977             if ((dce->flags & DCX_CACHE) && !dce->count)
 978             {
 979                 dceUnused = dce;
 980
 981                 if (!dce->hwnd) dceEmpty = dce;
 982                 else if ((dce->hwnd == hwnd) && !((dce->flags ^ flags) & clip_flags))
 983                 {
 984                     TRACE("\tfound valid %p dce [%p], flags %08x\n",
 985                           dce, hwnd, dce->flags );
 986                     bUpdateVisRgn = FALSE;
 987                     break;
 988                 }
 989             }
 990         }
 991
 992         if (&dce->entry == &dce_list)  /* nothing found */
 993             dce = dceEmpty ? dceEmpty : dceUnused;
 994
 995         if (dce) dce->count = 1;
 996
 997         USER_Unlock();
 998
 999         /* if there's no dce empty or unused, allocate a new one */
1000         if (!dce)
1001         {
1002             if (!(dce = alloc_dce())) return 0;
1003             dce->flags = DCX_CACHE;
1004             USER_Lock();
1005             list_add_head( &dce_list, &dce->entry );
1006             USER_Unlock();
1007         }
1008     }
1009     else
1010     {
1011         flags |= DCX_NORESETATTRS;
1012         if (dce->hwnd == hwnd)
1013         {
1014             TRACE("\tskipping hVisRgn update\n");
1015             bUpdateVisRgn = FALSE; /* updated automatically, via DCHook() */
1016         }
1017         else
1018         {
1019             /* we should free dce->clip_rgn here, but Windows apparently doesn't */
1020             dce->flags &= ~(DCX_EXCLUDERGN | DCX_INTERSECTRGN);
1021             dce->clip_rgn = 0;
1022         }
1023     }
1024
1025     if (flags & (DCX_INTERSECTRGN | DCX_EXCLUDERGN))
1026     {
1027         /* if the extra clip region has changed, get rid of the old one */
1028         if (dce->clip_rgn != hrgnClip || ((flags ^ dce->flags) & (DCX_INTERSECTRGN | DCX_EXCLUDERGN)))
1029             delete_clip_rgn( dce );
1030         dce->clip_rgn = hrgnClip;
1031         if (!dce->clip_rgn) dce->clip_rgn = CreateRectRgn( 0, 0, 0, 0 );
1032         dce->flags |= flags & (DCX_INTERSECTRGN | DCX_EXCLUDERGN);
1033         bUpdateVisRgn = TRUE;
1034     }
1035
1036     dce->hwnd = hwnd;
1037     dce->flags = (dce->flags & ~user_flags) | (flags & user_flags);
1038
1039     if (SetHookFlags( dce->hdc, DCHF_VALIDATEVISRGN )) bUpdateVisRgn = TRUE;  /* DC was dirty */
1040
1041     if (bUpdateVisRgn) update_visible_region( dce );
1042
1043     TRACE("(%p,%p,0x%x): returning %p\n", hwnd, hrgnClip, flags, dce->hdc);
1044     return dce->hdc;
1045 }
1046
1047
1048 /***********************************************************************
1049  *              GetDC (USER32.@)
1050  *
1051  * Get a device context.
1052  *
1053  * RETURNS
1054  *      Success: Handle to the device context
1055  *      Failure: NULL.
1056  */
1057 HDC WINAPI GetDC( HWND hwnd )
1058 {
1059     if (!hwnd) return GetDCEx( 0, 0, DCX_CACHE | DCX_WINDOW );
1060     return GetDCEx( hwnd, 0, DCX_USESTYLE );
1061 }
1062
1063
1064 /***********************************************************************
1065  *              GetWindowDC (USER32.@)
1066  */
1067 HDC WINAPI GetWindowDC( HWND hwnd )
1068 {
1069     return GetDCEx( hwnd, 0, DCX_USESTYLE | DCX_WINDOW );
1070 }
1071
1072
1073 /***********************************************************************
1074  *              ReleaseDC (USER32.@)
1075  *
1076  * Release a device context.
1077  *
1078  * RETURNS
1079  *      Success: Non-zero. Resources used by hdc are released.
1080  *      Failure: 0.
1081  */
1082 INT WINAPI ReleaseDC( HWND hwnd, HDC hdc )
1083 {
1084     return release_dc( hwnd, hdc, FALSE );
1085 }
1086
1087
1088 /**********************************************************************
1089  *              WindowFromDC (USER32.@)
1090  */
1091 HWND WINAPI WindowFromDC( HDC hdc )
1092 {
1093     struct dce *dce;
1094     HWND hwnd = 0;
1095
1096     USER_Lock();
1097     dce = (struct dce *)GetDCHook( hdc, NULL );
1098     if (dce) hwnd = dce->hwnd;
1099     USER_Unlock();
1100     return hwnd;
1101 }
1102
1103
1104 /***********************************************************************
1105  *              LockWindowUpdate (USER32.@)
1106  *
1107  * Enables or disables painting in the chosen window.
1108  *
1109  * PARAMS
1110  *  hwnd [I] handle to a window.
1111  *
1112  * RETURNS
1113  *  If successful, returns nonzero value. Otherwise,
1114  *  returns 0.
1115  *
1116  * NOTES
1117  *  You can lock only one window at a time.
1118  */
1119 BOOL WINAPI LockWindowUpdate( HWND hwnd )
1120 {
1121     static HWND lockedWnd;
1122
1123     FIXME("(%p), partial stub!\n",hwnd);
1124
1125     USER_Lock();
1126     if (lockedWnd)
1127     {
1128         if (!hwnd)
1129         {
1130             /* Unlock lockedWnd */
1131             /* FIXME: Do something */
1132         }
1133         else
1134         {
1135             /* Attempted to lock a second window */
1136             /* Return FALSE and do nothing */
1137             USER_Unlock();
1138             return FALSE;
1139         }
1140     }
1141     lockedWnd = hwnd;
1142     USER_Unlock();
1143     return TRUE;
1144 }
1145
1146
1147 /***********************************************************************
1148  *              RedrawWindow (USER32.@)
1149  */
1150 BOOL WINAPI RedrawWindow( HWND hwnd, const RECT *rect, HRGN hrgn, UINT flags )
1151 {
1152     static const RECT empty;
1153     BOOL ret;
1154
1155     if (!hwnd) hwnd = GetDesktopWindow();
1156
1157     if (TRACE_ON(win))
1158     {
1159         if (hrgn)
1160         {
1161             RECT r;
1162             GetRgnBox( hrgn, &r );
1163             TRACE( "%p region %p box %s ", hwnd, hrgn, wine_dbgstr_rect(&r) );
1164         }
1165         else if (rect)
1166             TRACE( "%p rect %s ", hwnd, wine_dbgstr_rect(rect) );
1167         else
1168             TRACE( "%p whole window ", hwnd );
1169
1170         dump_rdw_flags(flags);
1171     }
1172
1173     /* process pending expose events before painting */
1174     if (flags & RDW_UPDATENOW) USER_Driver->pMsgWaitForMultipleObjectsEx( 0, NULL, 0, QS_PAINT, 0 );
1175
1176     if (rect && !hrgn)
1177     {
1178         if (IsRectEmpty( rect )) rect = &empty;
1179         ret = redraw_window_rects( hwnd, flags, rect, 1 );
1180     }
1181     else if (!hrgn)
1182     {
1183         ret = redraw_window_rects( hwnd, flags, NULL, 0 );
1184     }
1185     else  /* need to build a list of the region rectangles */
1186     {
1187         DWORD size;
1188         RGNDATA *data = NULL;
1189
1190         if (!(size = GetRegionData( hrgn, 0, NULL ))) return FALSE;
1191         if (!(data = HeapAlloc( GetProcessHeap(), 0, size ))) return FALSE;
1192         GetRegionData( hrgn, size, data );
1193         if (!data->rdh.nCount)  /* empty region -> use a single all-zero rectangle */
1194             ret = redraw_window_rects( hwnd, flags, &empty, 1 );
1195         else
1196             ret = redraw_window_rects( hwnd, flags, (const RECT *)data->Buffer, data->rdh.nCount );
1197         HeapFree( GetProcessHeap(), 0, data );
1198     }
1199
1200     if (flags & RDW_UPDATENOW) update_now( hwnd, flags );
1201     else if (flags & RDW_ERASENOW) erase_now( hwnd, flags );
1202
1203     return ret;
1204 }
1205
1206
1207 /***********************************************************************
1208  *              UpdateWindow (USER32.@)
1209  */
1210 BOOL WINAPI UpdateWindow( HWND hwnd )
1211 {
1212     return RedrawWindow( hwnd, NULL, 0, RDW_UPDATENOW | RDW_ALLCHILDREN );
1213 }
1214
1215
1216 /***********************************************************************
1217  *              InvalidateRgn (USER32.@)
1218  */
1219 BOOL WINAPI InvalidateRgn( HWND hwnd, HRGN hrgn, BOOL erase )
1220 {
1221     if (!hwnd)
1222     {
1223         SetLastError( ERROR_INVALID_WINDOW_HANDLE );
1224         return FALSE;
1225     }
1226
1227     return RedrawWindow(hwnd, NULL, hrgn, RDW_INVALIDATE | (erase ? RDW_ERASE : 0) );
1228 }
1229
1230
1231 /***********************************************************************
1232  *              InvalidateRect (USER32.@)
1233  *
1234  * MSDN: if hwnd parameter is NULL, InvalidateRect invalidates and redraws
1235  * all windows and sends WM_ERASEBKGND and WM_NCPAINT.
1236  */
1237 BOOL WINAPI InvalidateRect( HWND hwnd, const RECT *rect, BOOL erase )
1238 {
1239     UINT flags = RDW_INVALIDATE | (erase ? RDW_ERASE : 0);
1240
1241     if (!hwnd)
1242     {
1243         flags = RDW_ALLCHILDREN | RDW_INVALIDATE | RDW_FRAME | RDW_ERASE | RDW_ERASENOW;
1244         rect = NULL;
1245     }
1246
1247     return RedrawWindow( hwnd, rect, 0, flags );
1248 }
1249
1250
1251 /***********************************************************************
1252  *              ValidateRgn (USER32.@)
1253  */
1254 BOOL WINAPI ValidateRgn( HWND hwnd, HRGN hrgn )
1255 {
1256     if (!hwnd)
1257     {
1258         SetLastError( ERROR_INVALID_WINDOW_HANDLE );
1259         return FALSE;
1260     }
1261
1262     return RedrawWindow( hwnd, NULL, hrgn, RDW_VALIDATE );
1263 }
1264
1265
1266 /***********************************************************************
1267  *              ValidateRect (USER32.@)
1268  *
1269  * MSDN: if hwnd parameter is NULL, ValidateRect invalidates and redraws
1270  * all windows and sends WM_ERASEBKGND and WM_NCPAINT.
1271  */
1272 BOOL WINAPI ValidateRect( HWND hwnd, const RECT *rect )
1273 {
1274     UINT flags = RDW_VALIDATE;
1275
1276     if (!hwnd)
1277     {
1278         flags = RDW_ALLCHILDREN | RDW_INVALIDATE | RDW_FRAME | RDW_ERASE | RDW_ERASENOW;
1279         rect = NULL;
1280     }
1281
1282     return RedrawWindow( hwnd, rect, 0, flags );
1283 }
1284
1285
1286 /***********************************************************************
1287  *              GetUpdateRgn (USER32.@)
1288  */
1289 INT WINAPI GetUpdateRgn( HWND hwnd, HRGN hrgn, BOOL erase )
1290 {
1291     INT retval = ERROR;
1292     UINT flags = UPDATE_NOCHILDREN;
1293     HRGN update_rgn;
1294
1295     if (erase) flags |= UPDATE_NONCLIENT | UPDATE_ERASE;
1296
1297     if ((update_rgn = send_ncpaint( hwnd, NULL, &flags )))
1298     {
1299         POINT offset;
1300
1301         retval = CombineRgn( hrgn, update_rgn, 0, RGN_COPY );
1302         if (send_erase( hwnd, flags, update_rgn, NULL, NULL ))
1303         {
1304             flags = UPDATE_DELAYED_ERASE;
1305             get_update_flags( hwnd, NULL, &flags );
1306         }
1307         /* map region to client coordinates */
1308         offset.x = offset.y = 0;
1309         ScreenToClient( hwnd, &offset );
1310         OffsetRgn( hrgn, offset.x, offset.y );
1311     }
1312     return retval;
1313 }
1314
1315
1316 /***********************************************************************
1317  *              GetUpdateRect (USER32.@)
1318  */
1319 BOOL WINAPI GetUpdateRect( HWND hwnd, LPRECT rect, BOOL erase )
1320 {
1321     UINT flags = UPDATE_NOCHILDREN;
1322     HRGN update_rgn;
1323     BOOL need_erase;
1324
1325     if (erase) flags |= UPDATE_NONCLIENT | UPDATE_ERASE;
1326
1327     if (!(update_rgn = send_ncpaint( hwnd, NULL, &flags ))) return FALSE;
1328
1329     if (rect)
1330     {
1331         if (GetRgnBox( update_rgn, rect ) != NULLREGION)
1332         {
1333             HDC hdc = GetDCEx( hwnd, 0, DCX_USESTYLE );
1334             MapWindowPoints( 0, hwnd, (LPPOINT)rect, 2 );
1335             DPtoLP( hdc, (LPPOINT)rect, 2 );
1336             ReleaseDC( hwnd, hdc );
1337         }
1338     }
1339     need_erase = send_erase( hwnd, flags, update_rgn, NULL, NULL );
1340
1341     /* check if we still have an update region */
1342     flags = UPDATE_PAINT | UPDATE_NOCHILDREN;
1343     if (need_erase) flags |= UPDATE_DELAYED_ERASE;
1344     return (get_update_flags( hwnd, NULL, &flags ) && (flags & UPDATE_PAINT));
1345 }
1346
1347
1348 /***********************************************************************
1349  *              ExcludeUpdateRgn (USER32.@)
1350  */
1351 INT WINAPI ExcludeUpdateRgn( HDC hdc, HWND hwnd )
1352 {
1353     HRGN update_rgn = CreateRectRgn( 0, 0, 0, 0 );
1354     INT ret = GetUpdateRgn( hwnd, update_rgn, FALSE );
1355
1356     if (ret != ERROR)
1357     {
1358         POINT pt;
1359
1360         GetDCOrgEx( hdc, &pt );
1361         MapWindowPoints( 0, hwnd, &pt, 1 );
1362         OffsetRgn( update_rgn, -pt.x, -pt.y );
1363         ret = ExtSelectClipRgn( hdc, update_rgn, RGN_DIFF );
1364         DeleteObject( update_rgn );
1365     }
1366     return ret;
1367 }
1368
1369
1370 /*************************************************************************
1371  *              ScrollWindowEx (USER32.@)
1372  *
1373  * Note: contrary to what the doc says, pixels that are scrolled from the
1374  *      outside of clipRect to the inside are NOT painted.
1375  *
1376  */
1377 INT WINAPI ScrollWindowEx( HWND hwnd, INT dx, INT dy,
1378                            const RECT *rect, const RECT *clipRect,
1379                            HRGN hrgnUpdate, LPRECT rcUpdate,
1380                            UINT flags )
1381 {
1382     INT   retVal = NULLREGION;
1383     BOOL  bOwnRgn = TRUE;
1384     BOOL  bUpdate = (rcUpdate || hrgnUpdate || flags & (SW_INVALIDATE | SW_ERASE));
1385     int rdw_flags;
1386     HRGN  hrgnTemp;
1387     HRGN  hrgnWinupd = 0;
1388     HDC   hDC;
1389     RECT  rc, cliprc;
1390     HWND hwndCaret = NULL;
1391     BOOL moveCaret = FALSE;
1392     POINT newCaretPos;
1393
1394     TRACE( "%p, %d,%d hrgnUpdate=%p rcUpdate = %p %s %04x\n",
1395            hwnd, dx, dy, hrgnUpdate, rcUpdate, wine_dbgstr_rect(rect), flags );
1396     TRACE( "clipRect = %s\n", wine_dbgstr_rect(clipRect));
1397     if( flags & ~( SW_SCROLLCHILDREN | SW_INVALIDATE | SW_ERASE))
1398         FIXME("some flags (%04x) are unhandled\n", flags);
1399
1400     rdw_flags = (flags & SW_ERASE) && (flags & SW_INVALIDATE) ?
1401                                 RDW_INVALIDATE | RDW_ERASE  : RDW_INVALIDATE ;
1402
1403     if (!WIN_IsWindowDrawable( hwnd, TRUE )) return ERROR;
1404     hwnd = WIN_GetFullHandle( hwnd );
1405
1406     GetClientRect(hwnd, &rc);
1407
1408     if (clipRect) IntersectRect(&cliprc,&rc,clipRect);
1409     else cliprc = rc;
1410
1411     if (rect) IntersectRect(&rc, &rc, rect);
1412
1413     if( hrgnUpdate ) bOwnRgn = FALSE;
1414     else if( bUpdate ) hrgnUpdate = CreateRectRgn( 0, 0, 0, 0 );
1415
1416     newCaretPos.x = newCaretPos.y = 0;
1417
1418     if( !IsRectEmpty(&cliprc) && (dx || dy)) {
1419         DWORD dcxflags = DCX_CACHE;
1420         DWORD style = GetWindowLongW( hwnd, GWL_STYLE );
1421
1422         hwndCaret = fix_caret(hwnd, &rc, dx, dy, flags, &moveCaret, &newCaretPos);
1423
1424         if( style & WS_CLIPSIBLINGS) dcxflags |= DCX_CLIPSIBLINGS;
1425         if( GetClassLongW( hwnd, GCL_STYLE ) & CS_PARENTDC)
1426             dcxflags |= DCX_PARENTCLIP;
1427         if( !(flags & SW_SCROLLCHILDREN) && (style & WS_CLIPCHILDREN))
1428             dcxflags |= DCX_CLIPCHILDREN;
1429         hDC = GetDCEx( hwnd, 0, dcxflags);
1430         if (hDC)
1431         {
1432             ScrollDC( hDC, dx, dy, &rc, &cliprc, hrgnUpdate, rcUpdate );
1433
1434             ReleaseDC( hwnd, hDC );
1435
1436             if (!bUpdate)
1437                 RedrawWindow( hwnd, NULL, hrgnUpdate, rdw_flags);
1438         }
1439
1440         /* If the windows has an update region, this must be
1441          * scrolled as well. Keep a copy in hrgnWinupd
1442          * to be added to hrngUpdate at the end. */
1443         hrgnTemp = CreateRectRgn( 0, 0, 0, 0 );
1444         retVal = GetUpdateRgn( hwnd, hrgnTemp, FALSE );
1445         if (retVal != NULLREGION)
1446         {
1447             HRGN hrgnClip = CreateRectRgnIndirect(&cliprc);
1448             if( !bOwnRgn) {
1449                 hrgnWinupd = CreateRectRgn( 0, 0, 0, 0);
1450                 CombineRgn( hrgnWinupd, hrgnTemp, 0, RGN_COPY);
1451             }
1452             OffsetRgn( hrgnTemp, dx, dy );
1453             CombineRgn( hrgnTemp, hrgnTemp, hrgnClip, RGN_AND );
1454             if( !bOwnRgn)
1455                 CombineRgn( hrgnWinupd, hrgnWinupd, hrgnTemp, RGN_OR );
1456             RedrawWindow( hwnd, NULL, hrgnTemp, rdw_flags);
1457
1458            /* Catch the case where the scrolling amount exceeds the size of the
1459             * original window. This generated a second update area that is the
1460             * location where the original scrolled content would end up.
1461             * This second region is not returned by the ScrollDC and sets
1462             * ScrollWindowEx apart from just a ScrollDC.
1463             *
1464             * This has been verified with testing on windows.
1465             */
1466             if (abs(dx) > abs(rc.right - rc.left) ||
1467                 abs(dy) > abs(rc.bottom - rc.top))
1468             {
1469                 SetRectRgn( hrgnTemp, rc.left + dx, rc.top + dy, rc.right+dx, rc.bottom + dy);
1470                 CombineRgn( hrgnTemp, hrgnTemp, hrgnClip, RGN_AND );
1471                 CombineRgn( hrgnUpdate, hrgnUpdate, hrgnTemp, RGN_OR );
1472
1473                 if( !bOwnRgn)
1474                     CombineRgn( hrgnWinupd, hrgnWinupd, hrgnTemp, RGN_OR );
1475             }
1476             DeleteObject( hrgnClip );
1477         }
1478         DeleteObject( hrgnTemp );
1479     } else {
1480         /* nothing was scrolled */
1481         if( !bOwnRgn)
1482             SetRectRgn( hrgnUpdate, 0, 0, 0, 0 );
1483         SetRectEmpty( rcUpdate);
1484     }
1485
1486     if( flags & SW_SCROLLCHILDREN )
1487     {
1488         HWND *list = WIN_ListChildren( hwnd );
1489         if (list)
1490         {
1491             int i;
1492             RECT r, dummy;
1493             for (i = 0; list[i]; i++)
1494             {
1495                 GetWindowRect( list[i], &r );
1496                 MapWindowPoints( 0, hwnd, (POINT *)&r, 2 );
1497                 if (!rect || IntersectRect(&dummy, &r, rect))
1498                     SetWindowPos( list[i], 0, r.left + dx, r.top  + dy, 0, 0,
1499                                   SWP_NOZORDER | SWP_NOSIZE | SWP_NOACTIVATE |
1500                                   SWP_NOREDRAW | SWP_DEFERERASE );
1501             }
1502             HeapFree( GetProcessHeap(), 0, list );
1503         }
1504     }
1505
1506     if( flags & (SW_INVALIDATE | SW_ERASE) )
1507         RedrawWindow( hwnd, NULL, hrgnUpdate, rdw_flags |
1508                       ((flags & SW_SCROLLCHILDREN) ? RDW_ALLCHILDREN : 0 ) );
1509
1510     if( hrgnWinupd) {
1511         CombineRgn( hrgnUpdate, hrgnUpdate, hrgnWinupd, RGN_OR);
1512         DeleteObject( hrgnWinupd);
1513     }
1514
1515     if( hwndCaret ) {
1516         if ( moveCaret ) SetCaretPos( newCaretPos.x, newCaretPos.y );
1517         ShowCaret(hwndCaret);
1518     }
1519
1520     if( bOwnRgn && hrgnUpdate ) DeleteObject( hrgnUpdate );
1521
1522     return retVal;
1523 }
1524
1525
1526 /*************************************************************************
1527  *              ScrollWindow (USER32.@)
1528  *
1529  */
1530 BOOL WINAPI ScrollWindow( HWND hwnd, INT dx, INT dy,
1531                           const RECT *rect, const RECT *clipRect )
1532 {
1533     return (ERROR != ScrollWindowEx( hwnd, dx, dy, rect, clipRect, 0, NULL,
1534                                      (rect ? 0 : SW_SCROLLCHILDREN) |
1535                                      SW_INVALIDATE | SW_ERASE ));
1536 }
1537
1538
1539 /*************************************************************************
1540  *              ScrollDC (USER32.@)
1541  *
1542  * dx, dy, lprcScroll and lprcClip are all in logical coordinates (msdn is
1543  * wrong) hrgnUpdate is returned in device coordinates with rcUpdate in
1544  * logical coordinates.
1545  */
1546 BOOL WINAPI ScrollDC( HDC hdc, INT dx, INT dy, const RECT *lprcScroll,
1547                       const RECT *lprcClip, HRGN hrgnUpdate, LPRECT lprcUpdate )
1548
1549 {
1550     return USER_Driver->pScrollDC( hdc, dx, dy, lprcScroll, lprcClip, hrgnUpdate, lprcUpdate );
1551 }
1552
1553 /************************************************************************
1554  *              PrintWindow (USER32.@)
1555  *
1556  */
1557 BOOL WINAPI PrintWindow(HWND hwnd, HDC hdcBlt, UINT nFlags)
1558 {
1559     UINT flags = PRF_CHILDREN | PRF_ERASEBKGND | PRF_OWNED | PRF_CLIENT;
1560     if(!(nFlags & PW_CLIENTONLY))
1561     {
1562         flags |= PRF_NONCLIENT;
1563     }
1564     SendMessageW(hwnd, WM_PRINT, (WPARAM)hdcBlt, flags);
1565     return TRUE;
1566 }