dlls/gdi32/clipping.c

   1 /*
   2  * DC clipping functions
   3  *
   4  * Copyright 1993 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #include <stdarg.h>
  22 #include <stdlib.h>
  23 #include "windef.h"
  24 #include "winbase.h"
  25 #include "wingdi.h"
  26 #include "gdi_private.h"
  27 #include "wine/debug.h"
  28
  29 WINE_DEFAULT_DEBUG_CHANNEL(clipping);
  30
  31
  32 /***********************************************************************
  33  *           get_clip_region
  34  *
  35  * Return the total clip region (if any).
  36  */
  37 static inline HRGN get_clip_region( DC * dc )
  38 {
  39     if (dc->hMetaClipRgn) return dc->hMetaClipRgn;
  40     if (dc->hMetaRgn) return dc->hMetaRgn;
  41     return dc->hClipRgn;
  42 }
  43
  44
  45 /***********************************************************************
  46  *           CLIPPING_UpdateGCRegion
  47  *
  48  * Update the GC clip region when the ClipRgn or VisRgn have changed.
  49  */
  50 void CLIPPING_UpdateGCRegion( DC * dc )
  51 {
  52     HRGN clip_rgn;
  53
  54     /* update the intersection of meta and clip regions */
  55     if (dc->hMetaRgn && dc->hClipRgn)
  56     {
  57         if (!dc->hMetaClipRgn) dc->hMetaClipRgn = CreateRectRgn( 0, 0, 0, 0 );
  58         CombineRgn( dc->hMetaClipRgn, dc->hClipRgn, dc->hMetaRgn, RGN_AND );
  59         clip_rgn = dc->hMetaClipRgn;
  60     }
  61     else  /* only one is set, no need for an intersection */
  62     {
  63         if (dc->hMetaClipRgn) DeleteObject( dc->hMetaClipRgn );
  64         dc->hMetaClipRgn = 0;
  65         clip_rgn = dc->hMetaRgn ? dc->hMetaRgn : dc->hClipRgn;
  66     }
  67
  68     if (dc->funcs->pSetDeviceClipping)
  69         dc->funcs->pSetDeviceClipping( dc->physDev, dc->hVisRgn, clip_rgn );
  70 }
  71
  72 /***********************************************************************
  73  *           create_default_clip_region
  74  *
  75  * Create a default clipping region when none already exists.
  76  */
  77 static inline void create_default_clip_region( DC * dc )
  78 {
  79     UINT width, height;
  80
  81     if (dc->header.type == OBJ_MEMDC)
  82     {
  83         BITMAP bitmap;
  84
  85         GetObjectW( dc->hBitmap, sizeof(bitmap), &bitmap );
  86         width = bitmap.bmWidth;
  87         height = bitmap.bmHeight;
  88     }
  89     else
  90     {
  91         width = GetDeviceCaps( dc->hSelf, DESKTOPHORZRES );
  92         height = GetDeviceCaps( dc->hSelf, DESKTOPVERTRES );
  93     }
  94     dc->hClipRgn = CreateRectRgn( 0, 0, width, height );
  95 }
  96
  97
  98 /***********************************************************************
  99  *           SelectClipRgn    (GDI32.@)
 100  */
 101 INT WINAPI SelectClipRgn( HDC hdc, HRGN hrgn )
 102 {
 103     return ExtSelectClipRgn( hdc, hrgn, RGN_COPY );
 104 }
 105
 106
 107 /******************************************************************************
 108  *              ExtSelectClipRgn        [GDI32.@]
 109  */
 110 INT WINAPI ExtSelectClipRgn( HDC hdc, HRGN hrgn, INT fnMode )
 111 {
 112     INT retval;
 113     RECT rect;
 114     DC * dc = get_dc_ptr( hdc );
 115     if (!dc) return ERROR;
 116
 117     TRACE("%p %p %d\n", hdc, hrgn, fnMode );
 118
 119     update_dc( dc );
 120     if (dc->funcs->pExtSelectClipRgn)
 121     {
 122         retval = dc->funcs->pExtSelectClipRgn( dc->physDev, hrgn, fnMode );
 123         release_dc_ptr( dc );
 124         return retval;
 125     }
 126
 127     if (!hrgn)
 128     {
 129         if (fnMode == RGN_COPY)
 130         {
 131             if (dc->hClipRgn) DeleteObject( dc->hClipRgn );
 132             dc->hClipRgn = 0;
 133         }
 134         else
 135         {
 136             FIXME("Unimplemented: hrgn NULL in mode: %d\n", fnMode);
 137             release_dc_ptr( dc );
 138             return ERROR;
 139         }
 140     }
 141     else
 142     {
 143         if (!dc->hClipRgn)
 144             create_default_clip_region( dc );
 145
 146         if(fnMode == RGN_COPY)
 147             CombineRgn( dc->hClipRgn, hrgn, 0, fnMode );
 148         else
 149             CombineRgn( dc->hClipRgn, dc->hClipRgn, hrgn, fnMode);
 150     }
 151
 152     CLIPPING_UpdateGCRegion( dc );
 153     release_dc_ptr( dc );
 154
 155     return GetClipBox(hdc, &rect);
 156 }
 157
 158 /***********************************************************************
 159  *           __wine_set_visible_region   (GDI32.@)
 160  */
 161 void CDECL __wine_set_visible_region( HDC hdc, HRGN hrgn, const RECT *vis_rect )
 162 {
 163     DC * dc;
 164
 165     if (!(dc = get_dc_ptr( hdc ))) return;
 166
 167     TRACE( "%p %p %s\n", hdc, hrgn, wine_dbgstr_rect(vis_rect) );
 168
 169     /* map region to DC coordinates */
 170     OffsetRgn( hrgn, -vis_rect->left, -vis_rect->top );
 171
 172     DeleteObject( dc->hVisRgn );
 173     dc->dirty = 0;
 174     dc->vis_rect = *vis_rect;
 175     dc->hVisRgn = hrgn;
 176     CLIPPING_UpdateGCRegion( dc );
 177     release_dc_ptr( dc );
 178 }
 179
 180
 181 /***********************************************************************
 182  *           OffsetClipRgn    (GDI32.@)
 183  */
 184 INT WINAPI OffsetClipRgn( HDC hdc, INT x, INT y )
 185 {
 186     INT ret = SIMPLEREGION;
 187     DC *dc = get_dc_ptr( hdc );
 188     if (!dc) return ERROR;
 189
 190     TRACE("%p %d,%d\n", hdc, x, y );
 191
 192     update_dc( dc );
 193     if(dc->funcs->pOffsetClipRgn)
 194     {
 195         ret = dc->funcs->pOffsetClipRgn( dc->physDev, x, y );
 196         /* FIXME: ret is just a success flag, we should return a proper value */
 197     }
 198     else if (dc->hClipRgn) {
 199         ret = OffsetRgn( dc->hClipRgn, MulDiv( x, dc->vportExtX, dc->wndExtX ),
 200                          MulDiv( y, dc->vportExtY, dc->wndExtY ) );
 201         CLIPPING_UpdateGCRegion( dc );
 202     }
 203     release_dc_ptr( dc );
 204     return ret;
 205 }
 206
 207
 208 /***********************************************************************
 209  *           ExcludeClipRect    (GDI32.@)
 210  */
 211 INT WINAPI ExcludeClipRect( HDC hdc, INT left, INT top,
 212                                 INT right, INT bottom )
 213 {
 214     HRGN newRgn;
 215     INT ret;
 216     DC *dc = get_dc_ptr( hdc );
 217     if (!dc) return ERROR;
 218
 219     TRACE("%p %dx%d,%dx%d\n", hdc, left, top, right, bottom );
 220
 221     update_dc( dc );
 222     if(dc->funcs->pExcludeClipRect)
 223     {
 224         ret = dc->funcs->pExcludeClipRect( dc->physDev, left, top, right, bottom );
 225         /* FIXME: ret is just a success flag, we should return a proper value */
 226     }
 227     else
 228     {
 229         POINT pt[2];
 230
 231         pt[0].x = left;
 232         pt[0].y = top;
 233         pt[1].x = right;
 234         pt[1].y = bottom;
 235         LPtoDP( hdc, pt, 2 );
 236         if (!(newRgn = CreateRectRgn( pt[0].x, pt[0].y, pt[1].x, pt[1].y ))) ret = ERROR;
 237         else
 238         {
 239             if (!dc->hClipRgn)
 240                 create_default_clip_region( dc );
 241             ret = CombineRgn( dc->hClipRgn, dc->hClipRgn, newRgn, RGN_DIFF );
 242             DeleteObject( newRgn );
 243         }
 244         if (ret != ERROR) CLIPPING_UpdateGCRegion( dc );
 245     }
 246     release_dc_ptr( dc );
 247     return ret;
 248 }
 249
 250
 251 /***********************************************************************
 252  *           IntersectClipRect    (GDI32.@)
 253  */
 254 INT WINAPI IntersectClipRect( HDC hdc, INT left, INT top, INT right, INT bottom )
 255 {
 256     INT ret;
 257     DC *dc = get_dc_ptr( hdc );
 258     if (!dc) return ERROR;
 259
 260     TRACE("%p %d,%d - %d,%d\n", hdc, left, top, right, bottom );
 261
 262     update_dc( dc );
 263     if(dc->funcs->pIntersectClipRect)
 264     {
 265         ret = dc->funcs->pIntersectClipRect( dc->physDev, left, top, right, bottom );
 266         /* FIXME: ret is just a success flag, we should return a proper value */
 267     }
 268     else
 269     {
 270         POINT pt[2];
 271
 272         pt[0].x = left;
 273         pt[0].y = top;
 274         pt[1].x = right;
 275         pt[1].y = bottom;
 276
 277         LPtoDP( hdc, pt, 2 );
 278
 279         if (!dc->hClipRgn)
 280         {
 281             dc->hClipRgn = CreateRectRgn( pt[0].x, pt[0].y, pt[1].x, pt[1].y );
 282             ret = SIMPLEREGION;
 283         }
 284         else
 285         {
 286             HRGN newRgn;
 287
 288             if (!(newRgn = CreateRectRgn( pt[0].x, pt[0].y, pt[1].x, pt[1].y ))) ret = ERROR;
 289             else
 290             {
 291                 ret = CombineRgn( dc->hClipRgn, dc->hClipRgn, newRgn, RGN_AND );
 292                 DeleteObject( newRgn );
 293             }
 294         }
 295         if (ret != ERROR) CLIPPING_UpdateGCRegion( dc );
 296     }
 297     release_dc_ptr( dc );
 298     return ret;
 299 }
 300
 301
 302 /***********************************************************************
 303  *           PtVisible    (GDI32.@)
 304  */
 305 BOOL WINAPI PtVisible( HDC hdc, INT x, INT y )
 306 {
 307     POINT pt;
 308     BOOL ret;
 309     HRGN clip;
 310     DC *dc = get_dc_ptr( hdc );
 311
 312     TRACE("%p %d,%d\n", hdc, x, y );
 313     if (!dc) return FALSE;
 314
 315     pt.x = x;
 316     pt.y = y;
 317     LPtoDP( hdc, &pt, 1 );
 318     update_dc( dc );
 319     ret = PtInRegion( dc->hVisRgn, pt.x, pt.y );
 320     if (ret && (clip = get_clip_region(dc))) ret = PtInRegion( clip, pt.x, pt.y );
 321     release_dc_ptr( dc );
 322     return ret;
 323 }
 324
 325
 326 /***********************************************************************
 327  *           RectVisible    (GDI32.@)
 328  */
 329 BOOL WINAPI RectVisible( HDC hdc, const RECT* rect )
 330 {
 331     RECT tmpRect;
 332     BOOL ret;
 333     HRGN clip;
 334     DC *dc = get_dc_ptr( hdc );
 335     if (!dc) return FALSE;
 336     TRACE("%p %d,%dx%d,%d\n", hdc, rect->left, rect->top, rect->right, rect->bottom );
 337
 338     tmpRect = *rect;
 339     LPtoDP( hdc, (POINT *)&tmpRect, 2 );
 340
 341     update_dc( dc );
 342     if ((clip = get_clip_region(dc)))
 343     {
 344         HRGN hrgn = CreateRectRgn( 0, 0, 0, 0 );
 345         CombineRgn( hrgn, dc->hVisRgn, clip, RGN_AND );
 346         ret = RectInRegion( hrgn, &tmpRect );
 347         DeleteObject( hrgn );
 348     }
 349     else ret = RectInRegion( dc->hVisRgn, &tmpRect );
 350     release_dc_ptr( dc );
 351     return ret;
 352 }
 353
 354
 355 /***********************************************************************
 356  *           GetClipBox    (GDI32.@)
 357  */
 358 INT WINAPI GetClipBox( HDC hdc, LPRECT rect )
 359 {
 360     INT ret;
 361     HRGN clip;
 362     DC *dc = get_dc_ptr( hdc );
 363     if (!dc) return ERROR;
 364
 365     update_dc( dc );
 366     if ((clip = get_clip_region(dc)))
 367     {
 368         HRGN hrgn = CreateRectRgn( 0, 0, 0, 0 );
 369         CombineRgn( hrgn, dc->hVisRgn, clip, RGN_AND );
 370         ret = GetRgnBox( hrgn, rect );
 371         DeleteObject( hrgn );
 372     }
 373     else ret = GetRgnBox( dc->hVisRgn, rect );
 374     DPtoLP( hdc, (LPPOINT)rect, 2 );
 375     release_dc_ptr( dc );
 376     return ret;
 377 }
 378
 379
 380 /***********************************************************************
 381  *           GetClipRgn  (GDI32.@)
 382  */
 383 INT WINAPI GetClipRgn( HDC hdc, HRGN hRgn )
 384 {
 385     INT ret = -1;
 386     DC * dc;
 387     if ((dc = get_dc_ptr( hdc )))
 388     {
 389       if( dc->hClipRgn )
 390       {
 391           if( CombineRgn(hRgn, dc->hClipRgn, 0, RGN_COPY) != ERROR ) ret = 1;
 392       }
 393       else ret = 0;
 394       release_dc_ptr( dc );
 395     }
 396     return ret;
 397 }
 398
 399
 400 /***********************************************************************
 401  *           GetMetaRgn    (GDI32.@)
 402  */
 403 INT WINAPI GetMetaRgn( HDC hdc, HRGN hRgn )
 404 {
 405     INT ret = 0;
 406     DC * dc = get_dc_ptr( hdc );
 407
 408     if (dc)
 409     {
 410         if (dc->hMetaRgn && CombineRgn( hRgn, dc->hMetaRgn, 0, RGN_COPY ) != ERROR)
 411             ret = 1;
 412         release_dc_ptr( dc );
 413     }
 414     return ret;
 415 }
 416
 417
 418 /***********************************************************************
 419  * GetRandomRgn [GDI32.@]
 420  *
 421  * NOTES
 422  *     This function is documented in MSDN online for the case of
 423  *     iCode == SYSRGN (4).
 424  *
 425  *     For iCode == 1 it should return the clip region
 426  *                  2 "    "       "   the meta region
 427  *                  3 "    "       "   the intersection of the clip with
 428  *                                     the meta region (== 'Rao' region).
 429  *
 430  *     See http://www.codeproject.com/gdi/cliprgnguide.asp
 431  */
 432 INT WINAPI GetRandomRgn(HDC hDC, HRGN hRgn, INT iCode)
 433 {
 434     HRGN rgn;
 435     DC *dc = get_dc_ptr( hDC );
 436
 437     if (!dc) return -1;
 438
 439     switch (iCode)
 440     {
 441     case 1:
 442         rgn = dc->hClipRgn;
 443         break;
 444     case 2:
 445         rgn = dc->hMetaRgn;
 446         break;
 447     case 3:
 448         rgn = dc->hMetaClipRgn;
 449         if(!rgn) rgn = dc->hClipRgn;
 450         if(!rgn) rgn = dc->hMetaRgn;
 451         break;
 452     case SYSRGN: /* == 4 */
 453         update_dc( dc );
 454         rgn = dc->hVisRgn;
 455         break;
 456     default:
 457         WARN("Unknown code %d\n", iCode);
 458         release_dc_ptr( dc );
 459         return -1;
 460     }
 461     if (rgn) CombineRgn( hRgn, rgn, 0, RGN_COPY );
 462     release_dc_ptr( dc );
 463
 464     /* On Windows NT/2000, the SYSRGN returned is in screen coordinates */
 465     if (iCode == SYSRGN && !(GetVersion() & 0x80000000))
 466     {
 467         POINT org;
 468         GetDCOrgEx( hDC, &org );
 469         OffsetRgn( hRgn, org.x, org.y );
 470     }
 471     return (rgn != 0);
 472 }
 473
 474
 475 /***********************************************************************
 476  *           SetMetaRgn    (GDI32.@)
 477  */
 478 INT WINAPI SetMetaRgn( HDC hdc )
 479 {
 480     INT ret;
 481     RECT dummy;
 482     DC *dc = get_dc_ptr( hdc );
 483
 484     if (!dc) return ERROR;
 485
 486     if (dc->hMetaClipRgn)
 487     {
 488         /* the intersection becomes the new meta region */
 489         DeleteObject( dc->hMetaRgn );
 490         DeleteObject( dc->hClipRgn );
 491         dc->hMetaRgn = dc->hMetaClipRgn;
 492         dc->hClipRgn = 0;
 493         dc->hMetaClipRgn = 0;
 494     }
 495     else if (dc->hClipRgn)
 496     {
 497         dc->hMetaRgn = dc->hClipRgn;
 498         dc->hClipRgn = 0;
 499     }
 500     /* else nothing to do */
 501
 502     /* Note: no need to call CLIPPING_UpdateGCRegion, the overall clip region hasn't changed */
 503
 504     ret = GetRgnBox( dc->hMetaRgn, &dummy );
 505     release_dc_ptr( dc );
 506     return ret;
 507 }