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  *           SelectVisRgn   (GDI32.@)
 160  *
 161  * Note: not exported on Windows, only the 16-bit version is exported.
 162  */
 163 INT WINAPI SelectVisRgn( HDC hdc, HRGN hrgn )
 164 {
 165     int retval;
 166     DC * dc;
 167
 168     if (!hrgn) return ERROR;
 169     if (!(dc = get_dc_ptr( hdc ))) return ERROR;
 170
 171     TRACE("%p %p\n", hdc, hrgn );
 172
 173     dc->dirty = 0;
 174
 175     retval = CombineRgn( dc->hVisRgn, hrgn, 0, RGN_COPY );
 176     CLIPPING_UpdateGCRegion( dc );
 177     release_dc_ptr( dc );
 178     return retval;
 179 }
 180
 181
 182 /***********************************************************************
 183  *           OffsetClipRgn    (GDI32.@)
 184  */
 185 INT WINAPI OffsetClipRgn( HDC hdc, INT x, INT y )
 186 {
 187     INT ret = SIMPLEREGION;
 188     DC *dc = get_dc_ptr( hdc );
 189     if (!dc) return ERROR;
 190
 191     TRACE("%p %d,%d\n", hdc, x, y );
 192
 193     update_dc( dc );
 194     if(dc->funcs->pOffsetClipRgn)
 195     {
 196         ret = dc->funcs->pOffsetClipRgn( dc->physDev, x, y );
 197         /* FIXME: ret is just a success flag, we should return a proper value */
 198     }
 199     else if (dc->hClipRgn) {
 200         ret = OffsetRgn( dc->hClipRgn, MulDiv( x, dc->vportExtX, dc->wndExtX ),
 201                          MulDiv( y, dc->vportExtY, dc->wndExtY ) );
 202         CLIPPING_UpdateGCRegion( dc );
 203     }
 204     release_dc_ptr( dc );
 205     return ret;
 206 }
 207
 208
 209 /***********************************************************************
 210  *           ExcludeClipRect    (GDI32.@)
 211  */
 212 INT WINAPI ExcludeClipRect( HDC hdc, INT left, INT top,
 213                                 INT right, INT bottom )
 214 {
 215     HRGN newRgn;
 216     INT ret;
 217     DC *dc = get_dc_ptr( hdc );
 218     if (!dc) return ERROR;
 219
 220     TRACE("%p %dx%d,%dx%d\n", hdc, left, top, right, bottom );
 221
 222     update_dc( dc );
 223     if(dc->funcs->pExcludeClipRect)
 224     {
 225         ret = dc->funcs->pExcludeClipRect( dc->physDev, left, top, right, bottom );
 226         /* FIXME: ret is just a success flag, we should return a proper value */
 227     }
 228     else
 229     {
 230         POINT pt[2];
 231
 232         pt[0].x = left;
 233         pt[0].y = top;
 234         pt[1].x = right;
 235         pt[1].y = bottom;
 236         LPtoDP( hdc, pt, 2 );
 237         if (!(newRgn = CreateRectRgn( pt[0].x, pt[0].y, pt[1].x, pt[1].y ))) ret = ERROR;
 238         else
 239         {
 240             if (!dc->hClipRgn)
 241                 create_default_clip_region( dc );
 242             ret = CombineRgn( dc->hClipRgn, dc->hClipRgn, newRgn, RGN_DIFF );
 243             DeleteObject( newRgn );
 244         }
 245         if (ret != ERROR) CLIPPING_UpdateGCRegion( dc );
 246     }
 247     release_dc_ptr( dc );
 248     return ret;
 249 }
 250
 251
 252 /***********************************************************************
 253  *           IntersectClipRect    (GDI32.@)
 254  */
 255 INT WINAPI IntersectClipRect( HDC hdc, INT left, INT top, INT right, INT bottom )
 256 {
 257     INT ret;
 258     DC *dc = get_dc_ptr( hdc );
 259     if (!dc) return ERROR;
 260
 261     TRACE("%p %d,%d - %d,%d\n", hdc, left, top, right, bottom );
 262
 263     update_dc( dc );
 264     if(dc->funcs->pIntersectClipRect)
 265     {
 266         ret = dc->funcs->pIntersectClipRect( dc->physDev, left, top, right, bottom );
 267         /* FIXME: ret is just a success flag, we should return a proper value */
 268     }
 269     else
 270     {
 271         POINT pt[2];
 272
 273         pt[0].x = left;
 274         pt[0].y = top;
 275         pt[1].x = right;
 276         pt[1].y = bottom;
 277
 278         LPtoDP( hdc, pt, 2 );
 279
 280         if (!dc->hClipRgn)
 281         {
 282             dc->hClipRgn = CreateRectRgn( pt[0].x, pt[0].y, pt[1].x, pt[1].y );
 283             ret = SIMPLEREGION;
 284         }
 285         else
 286         {
 287             HRGN newRgn;
 288
 289             if (!(newRgn = CreateRectRgn( pt[0].x, pt[0].y, pt[1].x, pt[1].y ))) ret = ERROR;
 290             else
 291             {
 292                 ret = CombineRgn( dc->hClipRgn, dc->hClipRgn, newRgn, RGN_AND );
 293                 DeleteObject( newRgn );
 294             }
 295         }
 296         if (ret != ERROR) CLIPPING_UpdateGCRegion( dc );
 297     }
 298     release_dc_ptr( dc );
 299     return ret;
 300 }
 301
 302
 303 /***********************************************************************
 304  *           PtVisible    (GDI32.@)
 305  */
 306 BOOL WINAPI PtVisible( HDC hdc, INT x, INT y )
 307 {
 308     POINT pt;
 309     BOOL ret;
 310     HRGN clip;
 311     DC *dc = get_dc_ptr( hdc );
 312
 313     TRACE("%p %d,%d\n", hdc, x, y );
 314     if (!dc) return FALSE;
 315
 316     pt.x = x;
 317     pt.y = y;
 318     LPtoDP( hdc, &pt, 1 );
 319     update_dc( dc );
 320     ret = PtInRegion( dc->hVisRgn, pt.x, pt.y );
 321     if (ret && (clip = get_clip_region(dc))) ret = PtInRegion( clip, pt.x, pt.y );
 322     release_dc_ptr( dc );
 323     return ret;
 324 }
 325
 326
 327 /***********************************************************************
 328  *           RectVisible    (GDI32.@)
 329  */
 330 BOOL WINAPI RectVisible( HDC hdc, const RECT* rect )
 331 {
 332     RECT tmpRect;
 333     BOOL ret;
 334     HRGN clip;
 335     DC *dc = get_dc_ptr( hdc );
 336     if (!dc) return FALSE;
 337     TRACE("%p %d,%dx%d,%d\n", hdc, rect->left, rect->top, rect->right, rect->bottom );
 338
 339     tmpRect = *rect;
 340     LPtoDP( hdc, (POINT *)&tmpRect, 2 );
 341
 342     update_dc( dc );
 343     if ((clip = get_clip_region(dc)))
 344     {
 345         HRGN hrgn = CreateRectRgn( 0, 0, 0, 0 );
 346         CombineRgn( hrgn, dc->hVisRgn, clip, RGN_AND );
 347         ret = RectInRegion( hrgn, &tmpRect );
 348         DeleteObject( hrgn );
 349     }
 350     else ret = RectInRegion( dc->hVisRgn, &tmpRect );
 351     release_dc_ptr( dc );
 352     return ret;
 353 }
 354
 355
 356 /***********************************************************************
 357  *           GetClipBox    (GDI32.@)
 358  */
 359 INT WINAPI GetClipBox( HDC hdc, LPRECT rect )
 360 {
 361     INT ret;
 362     HRGN clip;
 363     DC *dc = get_dc_ptr( hdc );
 364     if (!dc) return ERROR;
 365
 366     update_dc( dc );
 367     if ((clip = get_clip_region(dc)))
 368     {
 369         HRGN hrgn = CreateRectRgn( 0, 0, 0, 0 );
 370         CombineRgn( hrgn, dc->hVisRgn, clip, RGN_AND );
 371         ret = GetRgnBox( hrgn, rect );
 372         DeleteObject( hrgn );
 373     }
 374     else ret = GetRgnBox( dc->hVisRgn, rect );
 375     DPtoLP( hdc, (LPPOINT)rect, 2 );
 376     release_dc_ptr( dc );
 377     return ret;
 378 }
 379
 380
 381 /***********************************************************************
 382  *           GetClipRgn  (GDI32.@)
 383  */
 384 INT WINAPI GetClipRgn( HDC hdc, HRGN hRgn )
 385 {
 386     INT ret = -1;
 387     DC * dc;
 388     if (hRgn && (dc = get_dc_ptr( hdc )))
 389     {
 390       if( dc->hClipRgn )
 391       {
 392           if( CombineRgn(hRgn, dc->hClipRgn, 0, RGN_COPY) != ERROR ) ret = 1;
 393       }
 394       else ret = 0;
 395       release_dc_ptr( dc );
 396     }
 397     return ret;
 398 }
 399
 400
 401 /***********************************************************************
 402  *           GetMetaRgn    (GDI32.@)
 403  */
 404 INT WINAPI GetMetaRgn( HDC hdc, HRGN hRgn )
 405 {
 406     INT ret = 0;
 407     DC * dc = get_dc_ptr( hdc );
 408
 409     if (dc)
 410     {
 411         if (dc->hMetaRgn && CombineRgn( hRgn, dc->hMetaRgn, 0, RGN_COPY ) != ERROR)
 412             ret = 1;
 413         release_dc_ptr( dc );
 414     }
 415     return ret;
 416 }
 417
 418
 419 /***********************************************************************
 420  * GetRandomRgn [GDI32.@]
 421  *
 422  * NOTES
 423  *     This function is documented in MSDN online for the case of
 424  *     iCode == SYSRGN (4).
 425  *
 426  *     For iCode == 1 it should return the clip region
 427  *                  2 "    "       "   the meta region
 428  *                  3 "    "       "   the intersection of the clip with
 429  *                                     the meta region (== 'Rao' region).
 430  *
 431  *     See http://www.codeproject.com/gdi/cliprgnguide.asp
 432  */
 433 INT WINAPI GetRandomRgn(HDC hDC, HRGN hRgn, INT iCode)
 434 {
 435     HRGN rgn;
 436     DC *dc = get_dc_ptr( hDC );
 437
 438     if (!dc) return -1;
 439
 440     switch (iCode)
 441     {
 442     case 1:
 443         rgn = dc->hClipRgn;
 444         break;
 445     case 2:
 446         rgn = dc->hMetaRgn;
 447         break;
 448     case 3:
 449         rgn = dc->hMetaClipRgn;
 450         if(!rgn) rgn = dc->hClipRgn;
 451         if(!rgn) rgn = dc->hMetaRgn;
 452         break;
 453     case SYSRGN: /* == 4 */
 454         update_dc( dc );
 455         rgn = dc->hVisRgn;
 456         break;
 457     default:
 458         WARN("Unknown code %d\n", iCode);
 459         release_dc_ptr( dc );
 460         return -1;
 461     }
 462     if (rgn) CombineRgn( hRgn, rgn, 0, RGN_COPY );
 463     release_dc_ptr( dc );
 464
 465     /* On Windows NT/2000, the SYSRGN returned is in screen coordinates */
 466     if (iCode == SYSRGN && !(GetVersion() & 0x80000000))
 467     {
 468         POINT org;
 469         GetDCOrgEx( hDC, &org );
 470         OffsetRgn( hRgn, org.x, org.y );
 471     }
 472     return (rgn != 0);
 473 }
 474
 475
 476 /***********************************************************************
 477  *           SetMetaRgn    (GDI32.@)
 478  */
 479 INT WINAPI SetMetaRgn( HDC hdc )
 480 {
 481     INT ret;
 482     RECT dummy;
 483     DC *dc = get_dc_ptr( hdc );
 484
 485     if (!dc) return ERROR;
 486
 487     if (dc->hMetaClipRgn)
 488     {
 489         /* the intersection becomes the new meta region */
 490         DeleteObject( dc->hMetaRgn );
 491         DeleteObject( dc->hClipRgn );
 492         dc->hMetaRgn = dc->hMetaClipRgn;
 493         dc->hClipRgn = 0;
 494         dc->hMetaClipRgn = 0;
 495     }
 496     else if (dc->hClipRgn)
 497     {
 498         dc->hMetaRgn = dc->hClipRgn;
 499         dc->hClipRgn = 0;
 500     }
 501     /* else nothing to do */
 502
 503     /* Note: no need to call CLIPPING_UpdateGCRegion, the overall clip region hasn't changed */
 504
 505     ret = GetRgnBox( dc->hMetaRgn, &dummy );
 506     release_dc_ptr( dc );
 507     return ret;
 508 }