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 /* return the DC device rectangle if not empty */
  33 static inline BOOL get_dc_device_rect( DC *dc, RECT *rect )
  34 {
  35     *rect = dc->device_rect;
  36     offset_rect( rect, -dc->vis_rect.left, -dc->vis_rect.top );
  37     return !is_rect_empty( rect );
  38 }
  39
  40 /***********************************************************************
  41  *           get_clip_rect
  42  *
  43  * Compute a clip rectangle from its logical coordinates.
  44  */
  45 static inline RECT get_clip_rect( DC * dc, int left, int top, int right, int bottom )
  46 {
  47     RECT rect;
  48
  49     rect.left   = left;
  50     rect.top    = top;
  51     rect.right  = right;
  52     rect.bottom = bottom;
  53     LPtoDP( dc->hSelf, (POINT *)&rect, 2 );
  54     if (dc->layout & LAYOUT_RTL)
  55     {
  56         int tmp = rect.left;
  57         rect.left = rect.right + 1;
  58         rect.right = tmp + 1;
  59     }
  60     return rect;
  61 }
  62
  63 /***********************************************************************
  64  *           clip_device_rect
  65  *
  66  * Clip a rectangle to the whole DC surface.
  67  */
  68 BOOL clip_device_rect( DC *dc, RECT *dst, const RECT *src )
  69 {
  70     RECT clip;
  71
  72     if (get_dc_device_rect( dc, &clip )) return intersect_rect( dst, src, &clip );
  73     *dst = *src;
  74     return TRUE;
  75 }
  76
  77 /***********************************************************************
  78  *           clip_visrect
  79  *
  80  * Clip a rectangle to the DC visible rect.
  81  */
  82 BOOL clip_visrect( DC *dc, RECT *dst, const RECT *src )
  83 {
  84     RECT clip;
  85
  86     if (!clip_device_rect( dc, dst, src )) return FALSE;
  87     if (GetRgnBox( get_dc_region(dc), &clip )) return intersect_rect( dst, dst, &clip );
  88     return TRUE;
  89 }
  90
  91 /***********************************************************************
  92  *           update_dc_clipping
  93  *
  94  * Update the DC and device clip regions when the ClipRgn or VisRgn have changed.
  95  */
  96 void update_dc_clipping( DC * dc )
  97 {
  98     PHYSDEV physdev = GET_DC_PHYSDEV( dc, pSetDeviceClipping );
  99     HRGN regions[3];
 100     int count = 0;
 101
 102     if (dc->hVisRgn)  regions[count++] = dc->hVisRgn;
 103     if (dc->hClipRgn) regions[count++] = dc->hClipRgn;
 104     if (dc->hMetaRgn) regions[count++] = dc->hMetaRgn;
 105
 106     if (count > 1)
 107     {
 108         if (!dc->region) dc->region = CreateRectRgn( 0, 0, 0, 0 );
 109         CombineRgn( dc->region, regions[0], regions[1], RGN_AND );
 110         if (count > 2) CombineRgn( dc->region, dc->region, regions[2], RGN_AND );
 111     }
 112     else  /* only one region, we don't need the total region */
 113     {
 114         if (dc->region) DeleteObject( dc->region );
 115         dc->region = 0;
 116     }
 117     physdev->funcs->pSetDeviceClipping( physdev, get_dc_region( dc ));
 118 }
 119
 120 /***********************************************************************
 121  *           create_default_clip_region
 122  *
 123  * Create a default clipping region when none already exists.
 124  */
 125 static inline void create_default_clip_region( DC * dc )
 126 {
 127     RECT rect;
 128
 129     if (!get_dc_device_rect( dc, &rect ))
 130     {
 131         rect.left = 0;
 132         rect.top = 0;
 133         rect.right = GetDeviceCaps( dc->hSelf, DESKTOPHORZRES );
 134         rect.bottom = GetDeviceCaps( dc->hSelf, DESKTOPVERTRES );
 135     }
 136     dc->hClipRgn = CreateRectRgnIndirect( &rect );
 137 }
 138
 139
 140 /***********************************************************************
 141  *           null driver fallback implementations
 142  */
 143
 144 INT nulldrv_ExtSelectClipRgn( PHYSDEV dev, HRGN rgn, INT mode )
 145 {
 146     DC *dc = get_nulldrv_dc( dev );
 147     INT ret;
 148
 149     if (!rgn)
 150     {
 151         if (mode != RGN_COPY)
 152         {
 153             FIXME("Unimplemented: hrgn NULL in mode: %d\n", mode);
 154             return ERROR;
 155         }
 156         if (dc->hClipRgn) DeleteObject( dc->hClipRgn );
 157         dc->hClipRgn = 0;
 158         ret = SIMPLEREGION;
 159     }
 160     else
 161     {
 162         HRGN mirrored = 0;
 163
 164         if (dc->layout & LAYOUT_RTL)
 165         {
 166             if (!(mirrored = CreateRectRgn( 0, 0, 0, 0 ))) return ERROR;
 167             mirror_region( mirrored, rgn, dc->vis_rect.right - dc->vis_rect.left );
 168             rgn = mirrored;
 169         }
 170
 171         if (!dc->hClipRgn)
 172             create_default_clip_region( dc );
 173
 174         if (mode == RGN_COPY)
 175             ret = CombineRgn( dc->hClipRgn, rgn, 0, mode );
 176         else
 177             ret = CombineRgn( dc->hClipRgn, dc->hClipRgn, rgn, mode);
 178
 179         if (mirrored) DeleteObject( mirrored );
 180     }
 181     update_dc_clipping( dc );
 182     return ret;
 183 }
 184
 185 INT nulldrv_ExcludeClipRect( PHYSDEV dev, INT left, INT top, INT right, INT bottom )
 186 {
 187     DC *dc = get_nulldrv_dc( dev );
 188     RECT rect = get_clip_rect( dc, left, top, right, bottom );
 189     INT ret;
 190     HRGN rgn;
 191
 192     if (!(rgn = CreateRectRgnIndirect( &rect ))) return ERROR;
 193     if (!dc->hClipRgn) create_default_clip_region( dc );
 194     ret = CombineRgn( dc->hClipRgn, dc->hClipRgn, rgn, RGN_DIFF );
 195     DeleteObject( rgn );
 196     if (ret != ERROR) update_dc_clipping( dc );
 197     return ret;
 198 }
 199
 200 INT nulldrv_IntersectClipRect( PHYSDEV dev, INT left, INT top, INT right, INT bottom )
 201 {
 202     DC *dc = get_nulldrv_dc( dev );
 203     RECT rect = get_clip_rect( dc, left, top, right, bottom );
 204     INT ret;
 205     HRGN rgn;
 206
 207     if (!dc->hClipRgn)
 208     {
 209         dc->hClipRgn = CreateRectRgnIndirect( &rect );
 210         ret = SIMPLEREGION;
 211     }
 212     else
 213     {
 214         if (!(rgn = CreateRectRgnIndirect( &rect ))) return ERROR;
 215         ret = CombineRgn( dc->hClipRgn, dc->hClipRgn, rgn, RGN_AND );
 216         DeleteObject( rgn );
 217     }
 218     if (ret != ERROR) update_dc_clipping( dc );
 219     return ret;
 220 }
 221
 222 INT nulldrv_OffsetClipRgn( PHYSDEV dev, INT x, INT y )
 223 {
 224     DC *dc = get_nulldrv_dc( dev );
 225     INT ret = NULLREGION;
 226
 227     if (dc->hClipRgn)
 228     {
 229         x = MulDiv( x, dc->vportExtX, dc->wndExtX );
 230         y = MulDiv( y, dc->vportExtY, dc->wndExtY );
 231         if (dc->layout & LAYOUT_RTL) x = -x;
 232         ret = OffsetRgn( dc->hClipRgn, x, y );
 233         update_dc_clipping( dc );
 234     }
 235     return ret;
 236 }
 237
 238
 239 /***********************************************************************
 240  *           SelectClipRgn    (GDI32.@)
 241  */
 242 INT WINAPI SelectClipRgn( HDC hdc, HRGN hrgn )
 243 {
 244     return ExtSelectClipRgn( hdc, hrgn, RGN_COPY );
 245 }
 246
 247
 248 /******************************************************************************
 249  *              ExtSelectClipRgn        [GDI32.@]
 250  */
 251 INT WINAPI ExtSelectClipRgn( HDC hdc, HRGN hrgn, INT fnMode )
 252 {
 253     INT retval = ERROR;
 254     DC * dc = get_dc_ptr( hdc );
 255
 256     TRACE("%p %p %d\n", hdc, hrgn, fnMode );
 257
 258     if (dc)
 259     {
 260         PHYSDEV physdev = GET_DC_PHYSDEV( dc, pExtSelectClipRgn );
 261         update_dc( dc );
 262         retval = physdev->funcs->pExtSelectClipRgn( physdev, hrgn, fnMode );
 263         release_dc_ptr( dc );
 264     }
 265     return retval;
 266 }
 267
 268 /***********************************************************************
 269  *           __wine_set_visible_region   (GDI32.@)
 270  */
 271 void CDECL __wine_set_visible_region( HDC hdc, HRGN hrgn, const RECT *vis_rect )
 272 {
 273     DC * dc;
 274
 275     if (!(dc = get_dc_ptr( hdc ))) return;
 276
 277     TRACE( "%p %p %s\n", hdc, hrgn, wine_dbgstr_rect(vis_rect) );
 278
 279     /* map region to DC coordinates */
 280     OffsetRgn( hrgn, -vis_rect->left, -vis_rect->top );
 281
 282     if (dc->hVisRgn) DeleteObject( dc->hVisRgn );
 283     dc->dirty = 0;
 284     dc->vis_rect = *vis_rect;
 285     dc->hVisRgn = hrgn;
 286     DC_UpdateXforms( dc );
 287     update_dc_clipping( dc );
 288     release_dc_ptr( dc );
 289 }
 290
 291
 292 /***********************************************************************
 293  *           OffsetClipRgn    (GDI32.@)
 294  */
 295 INT WINAPI OffsetClipRgn( HDC hdc, INT x, INT y )
 296 {
 297     INT ret = ERROR;
 298     DC *dc = get_dc_ptr( hdc );
 299
 300     TRACE("%p %d,%d\n", hdc, x, y );
 301
 302     if (dc)
 303     {
 304         PHYSDEV physdev = GET_DC_PHYSDEV( dc, pOffsetClipRgn );
 305         update_dc( dc );
 306         ret = physdev->funcs->pOffsetClipRgn( physdev, x, y );
 307         release_dc_ptr( dc );
 308     }
 309     return ret;
 310 }
 311
 312
 313 /***********************************************************************
 314  *           ExcludeClipRect    (GDI32.@)
 315  */
 316 INT WINAPI ExcludeClipRect( HDC hdc, INT left, INT top,
 317                                 INT right, INT bottom )
 318 {
 319     INT ret = ERROR;
 320     DC *dc = get_dc_ptr( hdc );
 321
 322     TRACE("%p %d,%d-%d,%d\n", hdc, left, top, right, bottom );
 323
 324     if (dc)
 325     {
 326         PHYSDEV physdev = GET_DC_PHYSDEV( dc, pExcludeClipRect );
 327         update_dc( dc );
 328         ret = physdev->funcs->pExcludeClipRect( physdev, left, top, right, bottom );
 329         release_dc_ptr( dc );
 330     }
 331     return ret;
 332 }
 333
 334
 335 /***********************************************************************
 336  *           IntersectClipRect    (GDI32.@)
 337  */
 338 INT WINAPI IntersectClipRect( HDC hdc, INT left, INT top, INT right, INT bottom )
 339 {
 340     INT ret = ERROR;
 341     DC *dc = get_dc_ptr( hdc );
 342
 343     TRACE("%p %d,%d - %d,%d\n", hdc, left, top, right, bottom );
 344
 345     if (dc)
 346     {
 347         PHYSDEV physdev = GET_DC_PHYSDEV( dc, pIntersectClipRect );
 348         update_dc( dc );
 349         ret = physdev->funcs->pIntersectClipRect( physdev, left, top, right, bottom );
 350         release_dc_ptr( dc );
 351     }
 352     return ret;
 353 }
 354
 355
 356 /***********************************************************************
 357  *           PtVisible    (GDI32.@)
 358  */
 359 BOOL WINAPI PtVisible( HDC hdc, INT x, INT y )
 360 {
 361     POINT pt;
 362     RECT visrect;
 363     BOOL ret;
 364     DC *dc = get_dc_ptr( hdc );
 365
 366     TRACE("%p %d,%d\n", hdc, x, y );
 367     if (!dc) return FALSE;
 368
 369     pt.x = x;
 370     pt.y = y;
 371     LPtoDP( hdc, &pt, 1 );
 372     update_dc( dc );
 373     ret = (!get_dc_device_rect( dc, &visrect ) ||
 374            (pt.x >= visrect.left && pt.x < visrect.right &&
 375             pt.y >= visrect.top && pt.y < visrect.bottom));
 376     if (ret && get_dc_region( dc )) ret = PtInRegion( get_dc_region( dc ), pt.x, pt.y );
 377     release_dc_ptr( dc );
 378     return ret;
 379 }
 380
 381
 382 /***********************************************************************
 383  *           RectVisible    (GDI32.@)
 384  */
 385 BOOL WINAPI RectVisible( HDC hdc, const RECT* rect )
 386 {
 387     RECT tmpRect, visrect;
 388     BOOL ret;
 389     DC *dc = get_dc_ptr( hdc );
 390     if (!dc) return FALSE;
 391     TRACE("%p %s\n", hdc, wine_dbgstr_rect( rect ));
 392
 393     tmpRect = *rect;
 394     LPtoDP( hdc, (POINT *)&tmpRect, 2 );
 395
 396     update_dc( dc );
 397     ret = (!get_dc_device_rect( dc, &visrect ) || intersect_rect( &visrect, &visrect, &tmpRect ));
 398     if (ret && get_dc_region( dc )) ret = RectInRegion( get_dc_region( dc ), &tmpRect );
 399     release_dc_ptr( dc );
 400     return ret;
 401 }
 402
 403
 404 /***********************************************************************
 405  *           GetClipBox    (GDI32.@)
 406  */
 407 INT WINAPI GetClipBox( HDC hdc, LPRECT rect )
 408 {
 409     RECT visrect;
 410     INT ret;
 411     DC *dc = get_dc_ptr( hdc );
 412     if (!dc) return ERROR;
 413
 414     update_dc( dc );
 415     if (get_dc_region( dc ))
 416     {
 417         ret = GetRgnBox( get_dc_region( dc ), rect );
 418         if (get_dc_device_rect( dc, &visrect ) && !intersect_rect( rect, rect, &visrect ))
 419             ret = NULLREGION;
 420     }
 421     else
 422     {
 423         ret = is_rect_empty( &dc->vis_rect ) ? ERROR : SIMPLEREGION;
 424         *rect = dc->vis_rect;
 425     }
 426
 427     if (dc->layout & LAYOUT_RTL)
 428     {
 429         int tmp = rect->left;
 430         rect->left = rect->right - 1;
 431         rect->right = tmp - 1;
 432     }
 433     DPtoLP( hdc, (LPPOINT)rect, 2 );
 434     release_dc_ptr( dc );
 435     TRACE("%p => %d %s\n", hdc, ret, wine_dbgstr_rect( rect ));
 436     return ret;
 437 }
 438
 439
 440 /***********************************************************************
 441  *           GetClipRgn  (GDI32.@)
 442  */
 443 INT WINAPI GetClipRgn( HDC hdc, HRGN hRgn )
 444 {
 445     INT ret = -1;
 446     DC * dc;
 447     if ((dc = get_dc_ptr( hdc )))
 448     {
 449       if( dc->hClipRgn )
 450       {
 451           if( CombineRgn(hRgn, dc->hClipRgn, 0, RGN_COPY) != ERROR )
 452           {
 453               ret = 1;
 454               if (dc->layout & LAYOUT_RTL)
 455                   mirror_region( hRgn, hRgn, dc->vis_rect.right - dc->vis_rect.left );
 456           }
 457       }
 458       else ret = 0;
 459       release_dc_ptr( dc );
 460     }
 461     return ret;
 462 }
 463
 464
 465 /***********************************************************************
 466  *           GetMetaRgn    (GDI32.@)
 467  */
 468 INT WINAPI GetMetaRgn( HDC hdc, HRGN hRgn )
 469 {
 470     INT ret = 0;
 471     DC * dc = get_dc_ptr( hdc );
 472
 473     if (dc)
 474     {
 475         if (dc->hMetaRgn && CombineRgn( hRgn, dc->hMetaRgn, 0, RGN_COPY ) != ERROR)
 476         {
 477             ret = 1;
 478             if (dc->layout & LAYOUT_RTL)
 479                 mirror_region( hRgn, hRgn, dc->vis_rect.right - dc->vis_rect.left );
 480         }
 481         release_dc_ptr( dc );
 482     }
 483     return ret;
 484 }
 485
 486
 487 /***********************************************************************
 488  * GetRandomRgn [GDI32.@]
 489  *
 490  * NOTES
 491  *     This function is documented in MSDN online for the case of
 492  *     iCode == SYSRGN (4).
 493  *
 494  *     For iCode == 1 it should return the clip region
 495  *                  2 "    "       "   the meta region
 496  *                  3 "    "       "   the intersection of the clip with
 497  *                                     the meta region (== 'Rao' region).
 498  *
 499  *     See http://www.codeproject.com/gdi/cliprgnguide.asp
 500  */
 501 INT WINAPI GetRandomRgn(HDC hDC, HRGN hRgn, INT iCode)
 502 {
 503     INT ret = 1;
 504     DC *dc = get_dc_ptr( hDC );
 505
 506     if (!dc) return -1;
 507
 508     switch (iCode)
 509     {
 510     case 1:
 511         if (dc->hClipRgn) CombineRgn( hRgn, dc->hClipRgn, 0, RGN_COPY );
 512         else ret = 0;
 513         break;
 514     case 2:
 515         if (dc->hMetaRgn) CombineRgn( hRgn, dc->hMetaRgn, 0, RGN_COPY );
 516         else ret = 0;
 517         break;
 518     case 3:
 519         if (dc->hClipRgn && dc->hMetaRgn) CombineRgn( hRgn, dc->hClipRgn, dc->hMetaRgn, RGN_AND );
 520         else if (dc->hClipRgn) CombineRgn( hRgn, dc->hClipRgn, 0, RGN_COPY );
 521         else if (dc->hMetaRgn) CombineRgn( hRgn, dc->hMetaRgn, 0, RGN_COPY );
 522         else ret = 0;
 523         break;
 524     case SYSRGN: /* == 4 */
 525         update_dc( dc );
 526         if (dc->hVisRgn)
 527         {
 528             CombineRgn( hRgn, dc->hVisRgn, 0, RGN_COPY );
 529             /* On Windows NT/2000, the SYSRGN returned is in screen coordinates */
 530             if (!(GetVersion() & 0x80000000)) OffsetRgn( hRgn, dc->vis_rect.left, dc->vis_rect.top );
 531         }
 532         else if (!is_rect_empty( &dc->device_rect ))
 533             SetRectRgn( hRgn, dc->device_rect.left, dc->device_rect.top,
 534                         dc->device_rect.right, dc->device_rect.bottom );
 535         else
 536             ret = 0;
 537         break;
 538     default:
 539         WARN("Unknown code %d\n", iCode);
 540         ret = -1;
 541         break;
 542     }
 543     release_dc_ptr( dc );
 544     return ret;
 545 }
 546
 547
 548 /***********************************************************************
 549  *           SetMetaRgn    (GDI32.@)
 550  */
 551 INT WINAPI SetMetaRgn( HDC hdc )
 552 {
 553     INT ret;
 554     RECT dummy;
 555     DC *dc = get_dc_ptr( hdc );
 556
 557     if (!dc) return ERROR;
 558
 559     if (dc->hClipRgn)
 560     {
 561         if (dc->hMetaRgn)
 562         {
 563             /* the intersection becomes the new meta region */
 564             CombineRgn( dc->hMetaRgn, dc->hMetaRgn, dc->hClipRgn, RGN_AND );
 565             DeleteObject( dc->hClipRgn );
 566             dc->hClipRgn = 0;
 567         }
 568         else
 569         {
 570             dc->hMetaRgn = dc->hClipRgn;
 571             dc->hClipRgn = 0;
 572         }
 573     }
 574     /* else nothing to do */
 575
 576     /* Note: no need to call update_dc_clipping, the overall clip region hasn't changed */
 577
 578     ret = GetRgnBox( dc->hMetaRgn, &dummy );
 579     release_dc_ptr( dc );
 580     return ret;
 581 }