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     CLIPPING_UpdateGCRegion( dc );
 215     release_dc_ptr( dc );
 216 }
 217
 218
 219 /***********************************************************************
 220  *           OffsetClipRgn    (GDI32.@)
 221  */
 222 INT WINAPI OffsetClipRgn( HDC hdc, INT x, INT y )
 223 {
 224     INT ret = SIMPLEREGION;
 225     DC *dc = get_dc_ptr( hdc );
 226     if (!dc) return ERROR;
 227
 228     TRACE("%p %d,%d\n", hdc, x, y );
 229
 230     update_dc( dc );
 231     if(dc->funcs->pOffsetClipRgn)
 232     {
 233         ret = dc->funcs->pOffsetClipRgn( dc->physDev, x, y );
 234         /* FIXME: ret is just a success flag, we should return a proper value */
 235     }
 236     else if (dc->hClipRgn) {
 237         x = MulDiv( x, dc->vportExtX, dc->wndExtX );
 238         y = MulDiv( y, dc->vportExtY, dc->wndExtY );
 239         if (dc->layout & LAYOUT_RTL) x = -x;
 240         ret = OffsetRgn( dc->hClipRgn, x, y );
 241         CLIPPING_UpdateGCRegion( dc );
 242     }
 243     release_dc_ptr( dc );
 244     return ret;
 245 }
 246
 247
 248 /***********************************************************************
 249  *           ExcludeClipRect    (GDI32.@)
 250  */
 251 INT WINAPI ExcludeClipRect( HDC hdc, INT left, INT top,
 252                                 INT right, INT bottom )
 253 {
 254     HRGN newRgn;
 255     INT ret;
 256     DC *dc = get_dc_ptr( hdc );
 257     if (!dc) return ERROR;
 258
 259     TRACE("%p %dx%d,%dx%d\n", hdc, left, top, right, bottom );
 260
 261     update_dc( dc );
 262     if(dc->funcs->pExcludeClipRect)
 263     {
 264         ret = dc->funcs->pExcludeClipRect( dc->physDev, left, top, right, bottom );
 265         /* FIXME: ret is just a success flag, we should return a proper value */
 266     }
 267     else
 268     {
 269         RECT rect = get_clip_rect( dc, left, top, right, bottom );
 270
 271         if (!(newRgn = CreateRectRgnIndirect( &rect ))) ret = ERROR;
 272         else
 273         {
 274             if (!dc->hClipRgn)
 275                 create_default_clip_region( dc );
 276             ret = CombineRgn( dc->hClipRgn, dc->hClipRgn, newRgn, RGN_DIFF );
 277             DeleteObject( newRgn );
 278         }
 279         if (ret != ERROR) CLIPPING_UpdateGCRegion( dc );
 280     }
 281     release_dc_ptr( dc );
 282     return ret;
 283 }
 284
 285
 286 /***********************************************************************
 287  *           IntersectClipRect    (GDI32.@)
 288  */
 289 INT WINAPI IntersectClipRect( HDC hdc, INT left, INT top, INT right, INT bottom )
 290 {
 291     INT ret;
 292     DC *dc = get_dc_ptr( hdc );
 293     if (!dc) return ERROR;
 294
 295     TRACE("%p %d,%d - %d,%d\n", hdc, left, top, right, bottom );
 296
 297     update_dc( dc );
 298     if(dc->funcs->pIntersectClipRect)
 299     {
 300         ret = dc->funcs->pIntersectClipRect( dc->physDev, left, top, right, bottom );
 301         /* FIXME: ret is just a success flag, we should return a proper value */
 302     }
 303     else
 304     {
 305         RECT rect = get_clip_rect( dc, left, top, right, bottom );
 306
 307         if (!dc->hClipRgn)
 308         {
 309             dc->hClipRgn = CreateRectRgnIndirect( &rect );
 310             ret = SIMPLEREGION;
 311         }
 312         else
 313         {
 314             HRGN newRgn;
 315
 316             if (!(newRgn = CreateRectRgnIndirect( &rect ))) ret = ERROR;
 317             else
 318             {
 319                 ret = CombineRgn( dc->hClipRgn, dc->hClipRgn, newRgn, RGN_AND );
 320                 DeleteObject( newRgn );
 321             }
 322         }
 323         if (ret != ERROR) CLIPPING_UpdateGCRegion( dc );
 324     }
 325     release_dc_ptr( dc );
 326     return ret;
 327 }
 328
 329
 330 /***********************************************************************
 331  *           PtVisible    (GDI32.@)
 332  */
 333 BOOL WINAPI PtVisible( HDC hdc, INT x, INT y )
 334 {
 335     POINT pt;
 336     BOOL ret;
 337     HRGN clip;
 338     DC *dc = get_dc_ptr( hdc );
 339
 340     TRACE("%p %d,%d\n", hdc, x, y );
 341     if (!dc) return FALSE;
 342
 343     pt.x = x;
 344     pt.y = y;
 345     LPtoDP( hdc, &pt, 1 );
 346     update_dc( dc );
 347     ret = PtInRegion( dc->hVisRgn, pt.x, pt.y );
 348     if (ret && (clip = get_clip_region(dc))) ret = PtInRegion( clip, pt.x, pt.y );
 349     release_dc_ptr( dc );
 350     return ret;
 351 }
 352
 353
 354 /***********************************************************************
 355  *           RectVisible    (GDI32.@)
 356  */
 357 BOOL WINAPI RectVisible( HDC hdc, const RECT* rect )
 358 {
 359     RECT tmpRect;
 360     BOOL ret;
 361     HRGN clip;
 362     DC *dc = get_dc_ptr( hdc );
 363     if (!dc) return FALSE;
 364     TRACE("%p %d,%dx%d,%d\n", hdc, rect->left, rect->top, rect->right, rect->bottom );
 365
 366     tmpRect = *rect;
 367     LPtoDP( hdc, (POINT *)&tmpRect, 2 );
 368
 369     update_dc( dc );
 370     if ((clip = get_clip_region(dc)))
 371     {
 372         HRGN hrgn = CreateRectRgn( 0, 0, 0, 0 );
 373         CombineRgn( hrgn, dc->hVisRgn, clip, RGN_AND );
 374         ret = RectInRegion( hrgn, &tmpRect );
 375         DeleteObject( hrgn );
 376     }
 377     else ret = RectInRegion( dc->hVisRgn, &tmpRect );
 378     release_dc_ptr( dc );
 379     return ret;
 380 }
 381
 382
 383 /***********************************************************************
 384  *           GetClipBox    (GDI32.@)
 385  */
 386 INT WINAPI GetClipBox( HDC hdc, LPRECT rect )
 387 {
 388     INT ret;
 389     HRGN clip;
 390     DC *dc = get_dc_ptr( hdc );
 391     if (!dc) return ERROR;
 392
 393     update_dc( dc );
 394     if ((clip = get_clip_region(dc)))
 395     {
 396         HRGN hrgn = CreateRectRgn( 0, 0, 0, 0 );
 397         CombineRgn( hrgn, dc->hVisRgn, clip, RGN_AND );
 398         ret = GetRgnBox( hrgn, rect );
 399         DeleteObject( hrgn );
 400     }
 401     else ret = GetRgnBox( dc->hVisRgn, rect );
 402     DPtoLP( hdc, (LPPOINT)rect, 2 );
 403     release_dc_ptr( dc );
 404     return ret;
 405 }
 406
 407
 408 /***********************************************************************
 409  *           GetClipRgn  (GDI32.@)
 410  */
 411 INT WINAPI GetClipRgn( HDC hdc, HRGN hRgn )
 412 {
 413     INT ret = -1;
 414     DC * dc;
 415     if ((dc = get_dc_ptr( hdc )))
 416     {
 417       if( dc->hClipRgn )
 418       {
 419           if( CombineRgn(hRgn, dc->hClipRgn, 0, RGN_COPY) != ERROR )
 420           {
 421               ret = 1;
 422               if (dc->layout & LAYOUT_RTL)
 423                   mirror_region( hRgn, hRgn, dc->vis_rect.right - dc->vis_rect.left );
 424           }
 425       }
 426       else ret = 0;
 427       release_dc_ptr( dc );
 428     }
 429     return ret;
 430 }
 431
 432
 433 /***********************************************************************
 434  *           GetMetaRgn    (GDI32.@)
 435  */
 436 INT WINAPI GetMetaRgn( HDC hdc, HRGN hRgn )
 437 {
 438     INT ret = 0;
 439     DC * dc = get_dc_ptr( hdc );
 440
 441     if (dc)
 442     {
 443         if (dc->hMetaRgn && CombineRgn( hRgn, dc->hMetaRgn, 0, RGN_COPY ) != ERROR)
 444         {
 445             ret = 1;
 446             if (dc->layout & LAYOUT_RTL)
 447                 mirror_region( hRgn, hRgn, dc->vis_rect.right - dc->vis_rect.left );
 448         }
 449         release_dc_ptr( dc );
 450     }
 451     return ret;
 452 }
 453
 454
 455 /***********************************************************************
 456  * GetRandomRgn [GDI32.@]
 457  *
 458  * NOTES
 459  *     This function is documented in MSDN online for the case of
 460  *     iCode == SYSRGN (4).
 461  *
 462  *     For iCode == 1 it should return the clip region
 463  *                  2 "    "       "   the meta region
 464  *                  3 "    "       "   the intersection of the clip with
 465  *                                     the meta region (== 'Rao' region).
 466  *
 467  *     See http://www.codeproject.com/gdi/cliprgnguide.asp
 468  */
 469 INT WINAPI GetRandomRgn(HDC hDC, HRGN hRgn, INT iCode)
 470 {
 471     HRGN rgn;
 472     DC *dc = get_dc_ptr( hDC );
 473
 474     if (!dc) return -1;
 475
 476     switch (iCode)
 477     {
 478     case 1:
 479         rgn = dc->hClipRgn;
 480         break;
 481     case 2:
 482         rgn = dc->hMetaRgn;
 483         break;
 484     case 3:
 485         rgn = dc->hMetaClipRgn;
 486         if(!rgn) rgn = dc->hClipRgn;
 487         if(!rgn) rgn = dc->hMetaRgn;
 488         break;
 489     case SYSRGN: /* == 4 */
 490         update_dc( dc );
 491         rgn = dc->hVisRgn;
 492         break;
 493     default:
 494         WARN("Unknown code %d\n", iCode);
 495         release_dc_ptr( dc );
 496         return -1;
 497     }
 498     if (rgn) CombineRgn( hRgn, rgn, 0, RGN_COPY );
 499     release_dc_ptr( dc );
 500
 501     /* On Windows NT/2000, the SYSRGN returned is in screen coordinates */
 502     if (iCode == SYSRGN && !(GetVersion() & 0x80000000))
 503         OffsetRgn( hRgn, dc->vis_rect.left, dc->vis_rect.top );
 504
 505     return (rgn != 0);
 506 }
 507
 508
 509 /***********************************************************************
 510  *           SetMetaRgn    (GDI32.@)
 511  */
 512 INT WINAPI SetMetaRgn( HDC hdc )
 513 {
 514     INT ret;
 515     RECT dummy;
 516     DC *dc = get_dc_ptr( hdc );
 517
 518     if (!dc) return ERROR;
 519
 520     if (dc->hMetaClipRgn)
 521     {
 522         /* the intersection becomes the new meta region */
 523         DeleteObject( dc->hMetaRgn );
 524         DeleteObject( dc->hClipRgn );
 525         dc->hMetaRgn = dc->hMetaClipRgn;
 526         dc->hClipRgn = 0;
 527         dc->hMetaClipRgn = 0;
 528     }
 529     else if (dc->hClipRgn)
 530     {
 531         dc->hMetaRgn = dc->hClipRgn;
 532         dc->hClipRgn = 0;
 533     }
 534     /* else nothing to do */
 535
 536     /* Note: no need to call CLIPPING_UpdateGCRegion, the overall clip region hasn't changed */
 537
 538     ret = GetRgnBox( dc->hMetaRgn, &dummy );
 539     release_dc_ptr( dc );
 540     return ret;
 541 }