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  *           get_clip_rect
  47  *
  48  * Compute a clip rectangle from its logical coordinates.
  49  */
  50 static inline RECT get_clip_rect( DC * dc, int left, int top, int right, int bottom )
  51 {
  52     RECT rect;
  53
  54     rect.left   = left;
  55     rect.top    = top;
  56     rect.right  = right;
  57     rect.bottom = bottom;
  58     LPtoDP( dc->hSelf, (POINT *)&rect, 2 );
  59     if (dc->layout & LAYOUT_RTL)
  60     {
  61         int tmp = rect.left;
  62         rect.left = rect.right + 1;
  63         rect.right = tmp + 1;
  64     }
  65     return rect;
  66 }
  67
  68 /***********************************************************************
  69  *           CLIPPING_UpdateGCRegion
  70  *
  71  * Update the GC clip region when the ClipRgn or VisRgn have changed.
  72  */
  73 void CLIPPING_UpdateGCRegion( DC * dc )
  74 {
  75     HRGN clip_rgn;
  76
  77     /* update the intersection of meta and clip regions */
  78     if (dc->hMetaRgn && dc->hClipRgn)
  79     {
  80         if (!dc->hMetaClipRgn) dc->hMetaClipRgn = CreateRectRgn( 0, 0, 0, 0 );
  81         CombineRgn( dc->hMetaClipRgn, dc->hClipRgn, dc->hMetaRgn, RGN_AND );
  82         clip_rgn = dc->hMetaClipRgn;
  83     }
  84     else  /* only one is set, no need for an intersection */
  85     {
  86         if (dc->hMetaClipRgn) DeleteObject( dc->hMetaClipRgn );
  87         dc->hMetaClipRgn = 0;
  88         clip_rgn = dc->hMetaRgn ? dc->hMetaRgn : dc->hClipRgn;
  89     }
  90
  91     if (dc->funcs->pSetDeviceClipping)
  92         dc->funcs->pSetDeviceClipping( dc->physDev, dc->hVisRgn, clip_rgn );
  93 }
  94
  95 /***********************************************************************
  96  *           create_default_clip_region
  97  *
  98  * Create a default clipping region when none already exists.
  99  */
 100 static inline void create_default_clip_region( DC * dc )
 101 {
 102     UINT width, height;
 103
 104     if (dc->header.type == OBJ_MEMDC)
 105     {
 106         BITMAP bitmap;
 107
 108         GetObjectW( dc->hBitmap, sizeof(bitmap), &bitmap );
 109         width = bitmap.bmWidth;
 110         height = bitmap.bmHeight;
 111     }
 112     else
 113     {
 114         width = GetDeviceCaps( dc->hSelf, DESKTOPHORZRES );
 115         height = GetDeviceCaps( dc->hSelf, DESKTOPVERTRES );
 116     }
 117     dc->hClipRgn = CreateRectRgn( 0, 0, width, height );
 118 }
 119
 120
 121 /***********************************************************************
 122  *           SelectClipRgn    (GDI32.@)
 123  */
 124 INT WINAPI SelectClipRgn( HDC hdc, HRGN hrgn )
 125 {
 126     return ExtSelectClipRgn( hdc, hrgn, RGN_COPY );
 127 }
 128
 129
 130 /******************************************************************************
 131  *              ExtSelectClipRgn        [GDI32.@]
 132  */
 133 INT WINAPI ExtSelectClipRgn( HDC hdc, HRGN hrgn, INT fnMode )
 134 {
 135     INT retval;
 136     RECT rect;
 137     DC * dc = get_dc_ptr( hdc );
 138     if (!dc) return ERROR;
 139
 140     TRACE("%p %p %d\n", hdc, hrgn, fnMode );
 141
 142     update_dc( dc );
 143     if (dc->funcs->pExtSelectClipRgn)
 144     {
 145         retval = dc->funcs->pExtSelectClipRgn( dc->physDev, hrgn, fnMode );
 146         release_dc_ptr( dc );
 147         return retval;
 148     }
 149
 150     if (!hrgn)
 151     {
 152         if (fnMode == RGN_COPY)
 153         {
 154             if (dc->hClipRgn) DeleteObject( dc->hClipRgn );
 155             dc->hClipRgn = 0;
 156         }
 157         else
 158         {
 159             FIXME("Unimplemented: hrgn NULL in mode: %d\n", fnMode);
 160             release_dc_ptr( dc );
 161             return ERROR;
 162         }
 163     }
 164     else
 165     {
 166         HRGN mirrored = 0;
 167
 168         if (dc->layout & LAYOUT_RTL)
 169         {
 170             if (!(mirrored = CreateRectRgn( 0, 0, 0, 0 )))
 171             {
 172                 release_dc_ptr( dc );
 173                 return ERROR;
 174             }
 175             mirror_region( mirrored, hrgn, dc->vis_rect.right - dc->vis_rect.left );
 176             hrgn = mirrored;
 177         }
 178
 179         if (!dc->hClipRgn)
 180             create_default_clip_region( dc );
 181
 182         if(fnMode == RGN_COPY)
 183             CombineRgn( dc->hClipRgn, hrgn, 0, fnMode );
 184         else
 185             CombineRgn( dc->hClipRgn, dc->hClipRgn, hrgn, fnMode);
 186
 187         if (mirrored) DeleteObject( mirrored );
 188     }
 189
 190     CLIPPING_UpdateGCRegion( dc );
 191     release_dc_ptr( dc );
 192
 193     return GetClipBox(hdc, &rect);
 194 }
 195
 196 /***********************************************************************
 197  *           __wine_set_visible_region   (GDI32.@)
 198  */
 199 void CDECL __wine_set_visible_region( HDC hdc, HRGN hrgn, const RECT *vis_rect )
 200 {
 201     DC * dc;
 202
 203     if (!(dc = get_dc_ptr( hdc ))) return;
 204
 205     TRACE( "%p %p %s\n", hdc, hrgn, wine_dbgstr_rect(vis_rect) );
 206
 207     /* map region to DC coordinates */
 208     OffsetRgn( hrgn, -vis_rect->left, -vis_rect->top );
 209
 210     DeleteObject( dc->hVisRgn );
 211     dc->dirty = 0;
 212     dc->vis_rect = *vis_rect;
 213     dc->hVisRgn = hrgn;
 214     DC_UpdateXforms( dc );
 215     CLIPPING_UpdateGCRegion( dc );
 216     release_dc_ptr( dc );
 217 }
 218
 219
 220 /***********************************************************************
 221  *           OffsetClipRgn    (GDI32.@)
 222  */
 223 INT WINAPI OffsetClipRgn( HDC hdc, INT x, INT y )
 224 {
 225     INT ret = SIMPLEREGION;
 226     DC *dc = get_dc_ptr( hdc );
 227     if (!dc) return ERROR;
 228
 229     TRACE("%p %d,%d\n", hdc, x, y );
 230
 231     update_dc( dc );
 232     if(dc->funcs->pOffsetClipRgn)
 233     {
 234         ret = dc->funcs->pOffsetClipRgn( dc->physDev, x, y );
 235         /* FIXME: ret is just a success flag, we should return a proper value */
 236     }
 237     else if (dc->hClipRgn) {
 238         x = MulDiv( x, dc->vportExtX, dc->wndExtX );
 239         y = MulDiv( y, dc->vportExtY, dc->wndExtY );
 240         if (dc->layout & LAYOUT_RTL) x = -x;
 241         ret = OffsetRgn( dc->hClipRgn, x, y );
 242         CLIPPING_UpdateGCRegion( dc );
 243     }
 244     release_dc_ptr( dc );
 245     return ret;
 246 }
 247
 248
 249 /***********************************************************************
 250  *           ExcludeClipRect    (GDI32.@)
 251  */
 252 INT WINAPI ExcludeClipRect( HDC hdc, INT left, INT top,
 253                                 INT right, INT bottom )
 254 {
 255     HRGN newRgn;
 256     INT ret;
 257     DC *dc = get_dc_ptr( hdc );
 258     if (!dc) return ERROR;
 259
 260     TRACE("%p %dx%d,%dx%d\n", hdc, left, top, right, bottom );
 261
 262     update_dc( dc );
 263     if(dc->funcs->pExcludeClipRect)
 264     {
 265         ret = dc->funcs->pExcludeClipRect( 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         RECT rect = get_clip_rect( dc, left, top, right, bottom );
 271
 272         if (!(newRgn = CreateRectRgnIndirect( &rect ))) ret = ERROR;
 273         else
 274         {
 275             if (!dc->hClipRgn)
 276                 create_default_clip_region( dc );
 277             ret = CombineRgn( dc->hClipRgn, dc->hClipRgn, newRgn, RGN_DIFF );
 278             DeleteObject( newRgn );
 279         }
 280         if (ret != ERROR) CLIPPING_UpdateGCRegion( dc );
 281     }
 282     release_dc_ptr( dc );
 283     return ret;
 284 }
 285
 286
 287 /***********************************************************************
 288  *           IntersectClipRect    (GDI32.@)
 289  */
 290 INT WINAPI IntersectClipRect( HDC hdc, INT left, INT top, INT right, INT bottom )
 291 {
 292     INT ret;
 293     DC *dc = get_dc_ptr( hdc );
 294     if (!dc) return ERROR;
 295
 296     TRACE("%p %d,%d - %d,%d\n", hdc, left, top, right, bottom );
 297
 298     update_dc( dc );
 299     if(dc->funcs->pIntersectClipRect)
 300     {
 301         ret = dc->funcs->pIntersectClipRect( dc->physDev, left, top, right, bottom );
 302         /* FIXME: ret is just a success flag, we should return a proper value */
 303     }
 304     else
 305     {
 306         RECT rect = get_clip_rect( dc, left, top, right, bottom );
 307
 308         if (!dc->hClipRgn)
 309         {
 310             dc->hClipRgn = CreateRectRgnIndirect( &rect );
 311             ret = SIMPLEREGION;
 312         }
 313         else
 314         {
 315             HRGN newRgn;
 316
 317             if (!(newRgn = CreateRectRgnIndirect( &rect ))) ret = ERROR;
 318             else
 319             {
 320                 ret = CombineRgn( dc->hClipRgn, dc->hClipRgn, newRgn, RGN_AND );
 321                 DeleteObject( newRgn );
 322             }
 323         }
 324         if (ret != ERROR) CLIPPING_UpdateGCRegion( dc );
 325     }
 326     release_dc_ptr( dc );
 327     return ret;
 328 }
 329
 330
 331 /***********************************************************************
 332  *           PtVisible    (GDI32.@)
 333  */
 334 BOOL WINAPI PtVisible( HDC hdc, INT x, INT y )
 335 {
 336     POINT pt;
 337     BOOL ret;
 338     HRGN clip;
 339     DC *dc = get_dc_ptr( hdc );
 340
 341     TRACE("%p %d,%d\n", hdc, x, y );
 342     if (!dc) return FALSE;
 343
 344     pt.x = x;
 345     pt.y = y;
 346     LPtoDP( hdc, &pt, 1 );
 347     update_dc( dc );
 348     ret = PtInRegion( dc->hVisRgn, pt.x, pt.y );
 349     if (ret && (clip = get_clip_region(dc))) ret = PtInRegion( clip, pt.x, pt.y );
 350     release_dc_ptr( dc );
 351     return ret;
 352 }
 353
 354
 355 /***********************************************************************
 356  *           RectVisible    (GDI32.@)
 357  */
 358 BOOL WINAPI RectVisible( HDC hdc, const RECT* rect )
 359 {
 360     RECT tmpRect;
 361     BOOL ret;
 362     HRGN clip;
 363     DC *dc = get_dc_ptr( hdc );
 364     if (!dc) return FALSE;
 365     TRACE("%p %d,%dx%d,%d\n", hdc, rect->left, rect->top, rect->right, rect->bottom );
 366
 367     tmpRect = *rect;
 368     LPtoDP( hdc, (POINT *)&tmpRect, 2 );
 369
 370     update_dc( dc );
 371     if ((clip = get_clip_region(dc)))
 372     {
 373         HRGN hrgn = CreateRectRgn( 0, 0, 0, 0 );
 374         CombineRgn( hrgn, dc->hVisRgn, clip, RGN_AND );
 375         ret = RectInRegion( hrgn, &tmpRect );
 376         DeleteObject( hrgn );
 377     }
 378     else ret = RectInRegion( dc->hVisRgn, &tmpRect );
 379     release_dc_ptr( dc );
 380     return ret;
 381 }
 382
 383
 384 /***********************************************************************
 385  *           GetClipBox    (GDI32.@)
 386  */
 387 INT WINAPI GetClipBox( HDC hdc, LPRECT rect )
 388 {
 389     INT ret;
 390     HRGN clip;
 391     DC *dc = get_dc_ptr( hdc );
 392     if (!dc) return ERROR;
 393
 394     update_dc( dc );
 395     if ((clip = get_clip_region(dc)))
 396     {
 397         HRGN hrgn = CreateRectRgn( 0, 0, 0, 0 );
 398         CombineRgn( hrgn, dc->hVisRgn, clip, RGN_AND );
 399         ret = GetRgnBox( hrgn, rect );
 400         DeleteObject( hrgn );
 401     }
 402     else ret = GetRgnBox( dc->hVisRgn, rect );
 403     DPtoLP( hdc, (LPPOINT)rect, 2 );
 404     release_dc_ptr( dc );
 405     return ret;
 406 }
 407
 408
 409 /***********************************************************************
 410  *           GetClipRgn  (GDI32.@)
 411  */
 412 INT WINAPI GetClipRgn( HDC hdc, HRGN hRgn )
 413 {
 414     INT ret = -1;
 415     DC * dc;
 416     if ((dc = get_dc_ptr( hdc )))
 417     {
 418       if( dc->hClipRgn )
 419       {
 420           if( CombineRgn(hRgn, dc->hClipRgn, 0, RGN_COPY) != ERROR )
 421           {
 422               ret = 1;
 423               if (dc->layout & LAYOUT_RTL)
 424                   mirror_region( hRgn, hRgn, dc->vis_rect.right - dc->vis_rect.left );
 425           }
 426       }
 427       else ret = 0;
 428       release_dc_ptr( dc );
 429     }
 430     return ret;
 431 }
 432
 433
 434 /***********************************************************************
 435  *           GetMetaRgn    (GDI32.@)
 436  */
 437 INT WINAPI GetMetaRgn( HDC hdc, HRGN hRgn )
 438 {
 439     INT ret = 0;
 440     DC * dc = get_dc_ptr( hdc );
 441
 442     if (dc)
 443     {
 444         if (dc->hMetaRgn && CombineRgn( hRgn, dc->hMetaRgn, 0, RGN_COPY ) != ERROR)
 445         {
 446             ret = 1;
 447             if (dc->layout & LAYOUT_RTL)
 448                 mirror_region( hRgn, hRgn, dc->vis_rect.right - dc->vis_rect.left );
 449         }
 450         release_dc_ptr( dc );
 451     }
 452     return ret;
 453 }
 454
 455
 456 /***********************************************************************
 457  * GetRandomRgn [GDI32.@]
 458  *
 459  * NOTES
 460  *     This function is documented in MSDN online for the case of
 461  *     iCode == SYSRGN (4).
 462  *
 463  *     For iCode == 1 it should return the clip region
 464  *                  2 "    "       "   the meta region
 465  *                  3 "    "       "   the intersection of the clip with
 466  *                                     the meta region (== 'Rao' region).
 467  *
 468  *     See http://www.codeproject.com/gdi/cliprgnguide.asp
 469  */
 470 INT WINAPI GetRandomRgn(HDC hDC, HRGN hRgn, INT iCode)
 471 {
 472     HRGN rgn;
 473     DC *dc = get_dc_ptr( hDC );
 474
 475     if (!dc) return -1;
 476
 477     switch (iCode)
 478     {
 479     case 1:
 480         rgn = dc->hClipRgn;
 481         break;
 482     case 2:
 483         rgn = dc->hMetaRgn;
 484         break;
 485     case 3:
 486         rgn = dc->hMetaClipRgn;
 487         if(!rgn) rgn = dc->hClipRgn;
 488         if(!rgn) rgn = dc->hMetaRgn;
 489         break;
 490     case SYSRGN: /* == 4 */
 491         update_dc( dc );
 492         rgn = dc->hVisRgn;
 493         break;
 494     default:
 495         WARN("Unknown code %d\n", iCode);
 496         release_dc_ptr( dc );
 497         return -1;
 498     }
 499     if (rgn) CombineRgn( hRgn, rgn, 0, RGN_COPY );
 500     release_dc_ptr( dc );
 501
 502     /* On Windows NT/2000, the SYSRGN returned is in screen coordinates */
 503     if (iCode == SYSRGN && !(GetVersion() & 0x80000000))
 504         OffsetRgn( hRgn, dc->vis_rect.left, dc->vis_rect.top );
 505
 506     return (rgn != 0);
 507 }
 508
 509
 510 /***********************************************************************
 511  *           SetMetaRgn    (GDI32.@)
 512  */
 513 INT WINAPI SetMetaRgn( HDC hdc )
 514 {
 515     INT ret;
 516     RECT dummy;
 517     DC *dc = get_dc_ptr( hdc );
 518
 519     if (!dc) return ERROR;
 520
 521     if (dc->hMetaClipRgn)
 522     {
 523         /* the intersection becomes the new meta region */
 524         DeleteObject( dc->hMetaRgn );
 525         DeleteObject( dc->hClipRgn );
 526         dc->hMetaRgn = dc->hMetaClipRgn;
 527         dc->hClipRgn = 0;
 528         dc->hMetaClipRgn = 0;
 529     }
 530     else if (dc->hClipRgn)
 531     {
 532         dc->hMetaRgn = dc->hClipRgn;
 533         dc->hClipRgn = 0;
 534     }
 535     /* else nothing to do */
 536
 537     /* Note: no need to call CLIPPING_UpdateGCRegion, the overall clip region hasn't changed */
 538
 539     ret = GetRgnBox( dc->hMetaRgn, &dummy );
 540     release_dc_ptr( dc );
 541     return ret;
 542 }