dll/opengl/opengl32/wgl.c

   1 /*
   2  * COPYRIGHT:            See COPYING in the top level directory
   3  * PROJECT:              ReactOS
   4  * FILE:                 dll/opengl/opengl32/wgl.c
   5  * PURPOSE:              OpenGL32 DLL, WGL functions
   6  */
   7
   8 #include "opengl32.h"
   9
  10 #include <pseh/pseh2.h>
  11
  12 WINE_DEFAULT_DEBUG_CHANNEL(wgl);
  13
  14 static CRITICAL_SECTION dc_data_cs = {NULL, -1, 0, 0, 0, 0};
  15 static struct wgl_dc_data* dc_data_list = NULL;
  16
  17 LIST_ENTRY ContextListHead;
  18
  19 /* FIXME: suboptimal */
  20 static
  21 struct wgl_dc_data*
  22 get_dc_data(HDC hdc)
  23 {
  24     HWND hwnd = NULL;
  25     struct wgl_dc_data* data;
  26     DWORD objType = GetObjectType(hdc);
  27     ULONG flags = 0;
  28     union
  29     {
  30         HWND hwnd;
  31         HDC hdc;
  32         HANDLE u;
  33     } id;
  34
  35     /* Look for the right data identifier */
  36     if(objType == OBJ_DC)
  37     {
  38         hwnd = WindowFromDC(hdc);
  39         if(!hwnd)
  40             return NULL;
  41         id.hwnd = hwnd;
  42         flags = WGL_DC_OBJ_DC;
  43     }
  44     else if(objType == OBJ_MEMDC)
  45     {
  46         id.hdc = hdc;
  47     }
  48     else
  49     {
  50         return NULL;
  51     }
  52
  53     EnterCriticalSection(&dc_data_cs);
  54     data = dc_data_list;
  55     while(data)
  56     {
  57         if(data->owner.u == id.u)
  58         {
  59             LeaveCriticalSection(&dc_data_cs);
  60             return data;
  61         }
  62         data = data->next;
  63     }
  64     data= HeapAlloc(GetProcessHeap(), 0, sizeof(*data));
  65     if(!data)
  66     {
  67         LeaveCriticalSection(&dc_data_cs);
  68         return NULL;
  69     }
  70     /* initialize the structure */
  71     data->owner.u = id.u;
  72     data->flags = flags;
  73     data->pixelformat = 0;
  74     data->sw_data = NULL;
  75     /* Load the driver */
  76     data->icd_data = IntGetIcdData(hdc);
  77     /* Get the number of available formats for this DC once and for all */
  78     if(data->icd_data)
  79         data->nb_icd_formats = data->icd_data->DrvDescribePixelFormat(hdc, 0, 0, NULL);
  80     else
  81         data->nb_icd_formats = 0;
  82     TRACE("ICD %S has %u formats for HDC %x.\n", data->icd_data ? data->icd_data->DriverName : NULL, data->nb_icd_formats, hdc);
  83     data->nb_sw_formats = sw_DescribePixelFormat(hdc, 0, 0, NULL);
  84     data->next = dc_data_list;
  85     dc_data_list = data;
  86     LeaveCriticalSection(&dc_data_cs);
  87     return data;
  88 }
  89
  90 void release_dc_data(struct wgl_dc_data* dc_data)
  91 {
  92     (void)dc_data;
  93 }
  94
  95 struct wgl_context* get_context(HGLRC hglrc)
  96 {
  97     struct wgl_context* context = (struct wgl_context*)hglrc;
  98
  99     if(!hglrc)
 100         return NULL;
 101
 102     _SEH2_TRY
 103     {
 104         if(context->magic != 'GLRC')
 105             context = NULL;
 106     }
 107     _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
 108     {
 109         context = NULL;
 110     }
 111     _SEH2_END;
 112
 113     return context;
 114 }
 115
 116 INT WINAPI wglDescribePixelFormat(HDC hdc, INT format, UINT size, PIXELFORMATDESCRIPTOR *descr )
 117 {
 118     struct wgl_dc_data* dc_data = get_dc_data(hdc);
 119     INT ret;
 120
 121     if(!dc_data)
 122     {
 123         SetLastError(ERROR_INVALID_HANDLE);
 124         return 0;
 125     }
 126
 127     ret = dc_data->nb_icd_formats + dc_data->nb_sw_formats;
 128
 129     if(!descr)
 130     {
 131         release_dc_data(dc_data);
 132         return ret;
 133     }
 134     if((format == 0) || (format > ret) || (size != sizeof(*descr)))
 135     {
 136         release_dc_data(dc_data);
 137         SetLastError(ERROR_INVALID_PARAMETER);
 138         return 0;
 139     }
 140
 141     /* Query ICD if needed */
 142     if(format <= dc_data->nb_icd_formats)
 143     {
 144         struct ICD_Data* icd_data = dc_data->icd_data;
 145         /* SetPixelFormat may have NULLified this */
 146         if (!icd_data)
 147             icd_data = IntGetIcdData(hdc);
 148         if(!icd_data->DrvDescribePixelFormat(hdc, format, size, descr))
 149         {
 150             ret = 0;
 151         }
 152     }
 153     else
 154     {
 155         /* This is a software format */
 156         format -= dc_data->nb_icd_formats;
 157         if(!sw_DescribePixelFormat(hdc, format, size, descr))
 158         {
 159             ret = 0;
 160         }
 161     }
 162
 163     release_dc_data(dc_data);
 164     return ret;
 165 }
 166
 167 INT WINAPI wglChoosePixelFormat(HDC hdc, const PIXELFORMATDESCRIPTOR* ppfd)
 168 {
 169     PIXELFORMATDESCRIPTOR format, best;
 170     int i, count, best_format;
 171     int bestDBuffer = -1, bestStereo = -1;
 172
 173     TRACE_(wgl)( "%p %p: size %u version %u flags %u type %u color %u %u,%u,%u,%u "
 174                  "accum %u depth %u stencil %u aux %u\n",
 175                  hdc, ppfd, ppfd->nSize, ppfd->nVersion, ppfd->dwFlags, ppfd->iPixelType,
 176                  ppfd->cColorBits, ppfd->cRedBits, ppfd->cGreenBits, ppfd->cBlueBits, ppfd->cAlphaBits,
 177                  ppfd->cAccumBits, ppfd->cDepthBits, ppfd->cStencilBits, ppfd->cAuxBuffers );
 178
 179     count = wglDescribePixelFormat( hdc, 0, 0, NULL );
 180     if (!count) return 0;
 181
 182     best_format = 0;
 183     best.dwFlags = PFD_GENERIC_FORMAT;
 184     best.cAlphaBits = -1;
 185     best.cColorBits = -1;
 186     best.cDepthBits = -1;
 187     best.cStencilBits = -1;
 188     best.cAuxBuffers = -1;
 189
 190     for (i = 1; i <= count; i++)
 191     {
 192         if (!wglDescribePixelFormat( hdc, i, sizeof(format), &format )) continue;
 193
 194         if (ppfd->iPixelType != format.iPixelType)
 195         {
 196             TRACE( "pixel type mismatch for iPixelFormat=%d\n", i );
 197             continue;
 198         }
 199
 200         /* only use bitmap capable formats for bitmap rendering */
 201         if ((ppfd->dwFlags & PFD_DRAW_TO_BITMAP) != (format.dwFlags & PFD_DRAW_TO_BITMAP))
 202         {
 203             TRACE( "PFD_DRAW_TO_BITMAP mismatch for iPixelFormat=%d\n", i );
 204             continue;
 205         }
 206
 207         /* only use window capable formats for window rendering */
 208         if ((ppfd->dwFlags & PFD_DRAW_TO_WINDOW) != (format.dwFlags & PFD_DRAW_TO_WINDOW))
 209         {
 210             TRACE( "PFD_DRAW_TO_WINDOW mismatch for iPixelFormat=%d\n", i );
 211             continue;
 212         }
 213
 214         /* only use opengl capable formats for opengl rendering */
 215         if ((ppfd->dwFlags & PFD_SUPPORT_OPENGL) != (format.dwFlags & PFD_SUPPORT_OPENGL))
 216         {
 217             TRACE( "PFD_SUPPORT_OPENGL mismatch for iPixelFormat=%d\n", i );
 218             continue;
 219         }
 220
 221         /* only use GDI capable formats for GDI rendering */
 222         if ((ppfd->dwFlags & PFD_SUPPORT_GDI) != (format.dwFlags & PFD_SUPPORT_GDI))
 223         {
 224             TRACE( "PFD_SUPPORT_GDI mismatch for iPixelFormat=%d\n", i );
 225             continue;
 226         }
 227
 228         /* The behavior of PDF_STEREO/PFD_STEREO_DONTCARE and PFD_DOUBLEBUFFER / PFD_DOUBLEBUFFER_DONTCARE
 229          * is not very clear on MSDN. They specify that ChoosePixelFormat tries to match pixel formats
 230          * with the flag (PFD_STEREO / PFD_DOUBLEBUFFERING) set. Otherwise it says that it tries to match
 231          * formats without the given flag set.
 232          * A test on Windows using a Radeon 9500pro on WinXP (the driver doesn't support Stereo)
 233          * has indicated that a format without stereo is returned when stereo is unavailable.
 234          * So in case PFD_STEREO is set, formats that support it should have priority above formats
 235          * without. In case PFD_STEREO_DONTCARE is set, stereo is ignored.
 236          *
 237          * To summarize the following is most likely the correct behavior:
 238          * stereo not set -> prefer non-stereo formats, but also accept stereo formats
 239          * stereo set -> prefer stereo formats, but also accept non-stereo formats
 240          * stereo don't care -> it doesn't matter whether we get stereo or not
 241          *
 242          * In Wine we will treat non-stereo the same way as don't care because it makes
 243          * format selection even more complicated and second drivers with Stereo advertise
 244          * each format twice anyway.
 245          */
 246
 247         /* Doublebuffer, see the comments above */
 248         if (!(ppfd->dwFlags & PFD_DOUBLEBUFFER_DONTCARE))
 249         {
 250             if (((ppfd->dwFlags & PFD_DOUBLEBUFFER) != bestDBuffer) &&
 251                 ((format.dwFlags & PFD_DOUBLEBUFFER) == (ppfd->dwFlags & PFD_DOUBLEBUFFER)))
 252                 goto found;
 253
 254             if (bestDBuffer != -1 && (format.dwFlags & PFD_DOUBLEBUFFER) != bestDBuffer) continue;
 255         }
 256
 257         /* Stereo, see the comments above. */
 258         if (!(ppfd->dwFlags & PFD_STEREO_DONTCARE))
 259         {
 260             if (((ppfd->dwFlags & PFD_STEREO) != bestStereo) &&
 261                 ((format.dwFlags & PFD_STEREO) == (ppfd->dwFlags & PFD_STEREO)))
 262                 goto found;
 263
 264             if (bestStereo != -1 && (format.dwFlags & PFD_STEREO) != bestStereo) continue;
 265         }
 266
 267         /* Below we will do a number of checks to select the 'best' pixelformat.
 268          * We assume the precedence cColorBits > cAlphaBits > cDepthBits > cStencilBits -> cAuxBuffers.
 269          * The code works by trying to match the most important options as close as possible.
 270          * When a reasonable format is found, we will try to match more options.
 271          * It appears (see the opengl32 test) that Windows opengl drivers ignore options
 272          * like cColorBits, cAlphaBits and friends if they are set to 0, so they are considered
 273          * as DONTCARE. At least Serious Sam TSE relies on this behavior. */
 274
 275         if (ppfd->cColorBits)
 276         {
 277             if (((ppfd->cColorBits > best.cColorBits) && (format.cColorBits > best.cColorBits)) ||
 278                 ((format.cColorBits >= ppfd->cColorBits) && (format.cColorBits < best.cColorBits)))
 279                 goto found;
 280
 281             if (best.cColorBits != format.cColorBits)  /* Do further checks if the format is compatible */
 282             {
 283                 TRACE( "color mismatch for iPixelFormat=%d\n", i );
 284                 continue;
 285             }
 286         }
 287         if (ppfd->cAlphaBits)
 288         {
 289             if (((ppfd->cAlphaBits > best.cAlphaBits) && (format.cAlphaBits > best.cAlphaBits)) ||
 290                 ((format.cAlphaBits >= ppfd->cAlphaBits) && (format.cAlphaBits < best.cAlphaBits)))
 291                 goto found;
 292
 293             if (best.cAlphaBits != format.cAlphaBits)
 294             {
 295                 TRACE( "alpha mismatch for iPixelFormat=%d\n", i );
 296                 continue;
 297             }
 298         }
 299         if (ppfd->cDepthBits)
 300         {
 301             if (((ppfd->cDepthBits > best.cDepthBits) && (format.cDepthBits > best.cDepthBits)) ||
 302                 ((format.cDepthBits >= ppfd->cDepthBits) && (format.cDepthBits < best.cDepthBits)))
 303                 goto found;
 304
 305             if (best.cDepthBits != format.cDepthBits)
 306             {
 307                 TRACE( "depth mismatch for iPixelFormat=%d\n", i );
 308                 continue;
 309             }
 310         }
 311         if (ppfd->cStencilBits)
 312         {
 313             if (((ppfd->cStencilBits > best.cStencilBits) && (format.cStencilBits > best.cStencilBits)) ||
 314                 ((format.cStencilBits >= ppfd->cStencilBits) && (format.cStencilBits < best.cStencilBits)))
 315                 goto found;
 316
 317             if (best.cStencilBits != format.cStencilBits)
 318             {
 319                 TRACE( "stencil mismatch for iPixelFormat=%d\n", i );
 320                 continue;
 321             }
 322         }
 323         if (ppfd->cAuxBuffers)
 324         {
 325             if (((ppfd->cAuxBuffers > best.cAuxBuffers) && (format.cAuxBuffers > best.cAuxBuffers)) ||
 326                 ((format.cAuxBuffers >= ppfd->cAuxBuffers) && (format.cAuxBuffers < best.cAuxBuffers)))
 327                 goto found;
 328
 329             if (best.cAuxBuffers != format.cAuxBuffers)
 330             {
 331                 TRACE( "aux mismatch for iPixelFormat=%d\n", i );
 332                 continue;
 333             }
 334         }
 335         continue;
 336
 337     found:
 338         /* Prefer HW accelerated formats */
 339         if ((format.dwFlags & PFD_GENERIC_FORMAT) && !(best.dwFlags & PFD_GENERIC_FORMAT))
 340             continue;
 341         best_format = i;
 342         best = format;
 343         bestDBuffer = format.dwFlags & PFD_DOUBLEBUFFER;
 344         bestStereo = format.dwFlags & PFD_STEREO;
 345     }
 346
 347     TRACE( "returning %u\n", best_format );
 348     return best_format;
 349 }
 350
 351 BOOL WINAPI wglCopyContext(HGLRC hglrcSrc, HGLRC hglrcDst, UINT mask)
 352 {
 353     struct wgl_context* ctx_src = get_context(hglrcSrc);
 354     struct wgl_context* ctx_dst = get_context(hglrcDst);
 355
 356     if(!ctx_src || !ctx_dst)
 357     {
 358         SetLastError(ERROR_INVALID_HANDLE);
 359         return FALSE;
 360     }
 361
 362     /* Check this is the same pixel format */
 363     if((ctx_dst->icd_data != ctx_src->icd_data) ||
 364         (ctx_dst->pixelformat != ctx_src->pixelformat))
 365     {
 366         SetLastError(ERROR_INVALID_PIXEL_FORMAT);
 367         return FALSE;
 368     }
 369
 370     if(ctx_src->icd_data)
 371         return ctx_src->icd_data->DrvCopyContext(ctx_src->dhglrc, ctx_dst->dhglrc, mask);
 372
 373     return sw_CopyContext(ctx_src->dhglrc, ctx_dst->dhglrc, mask);
 374 }
 375
 376 HGLRC WINAPI wglCreateContext(HDC hdc)
 377 {
 378     struct wgl_dc_data* dc_data = get_dc_data(hdc);
 379     struct wgl_context* context;
 380     DHGLRC dhglrc;
 381
 382     TRACE("Creating context for %p.\n", hdc);
 383
 384     if(!dc_data)
 385     {
 386         WARN("Not a DC handle!\n");
 387         SetLastError(ERROR_INVALID_HANDLE);
 388         return NULL;
 389     }
 390
 391     if(!dc_data->pixelformat)
 392     {
 393         WARN("Pixel format not set!\n");
 394         SetLastError(ERROR_INVALID_PIXEL_FORMAT);
 395         return NULL;
 396     }
 397
 398     if(!dc_data->icd_data)
 399     {
 400         TRACE("Calling SW implementation.\n");
 401         dhglrc = sw_CreateContext(dc_data);
 402         TRACE("done\n");
 403     }
 404     else
 405     {
 406         TRACE("Calling ICD.\n");
 407         dhglrc = dc_data->icd_data->DrvCreateContext(hdc);
 408     }
 409
 410     if(!dhglrc)
 411     {
 412         WARN("Failed!\n");
 413         SetLastError(ERROR_INVALID_PIXEL_FORMAT);
 414         return NULL;
 415     }
 416
 417     context = HeapAlloc(GetProcessHeap(), 0, sizeof(*context));
 418     if(!context)
 419     {
 420         WARN("Failed to allocate a context!\n");
 421         if(!dc_data->icd_data)
 422             sw_DeleteContext(dhglrc);
 423         else
 424             dc_data->icd_data->DrvDeleteContext(dhglrc);
 425         SetLastError(ERROR_NOT_ENOUGH_MEMORY);
 426         return NULL;
 427     }
 428     /* Copy info from the DC data */
 429     context->dhglrc = dhglrc;
 430     context->icd_data = dc_data->icd_data;
 431     context->pixelformat = dc_data->pixelformat;
 432     context->thread_id = 0;
 433
 434     /* Insert into the list */
 435     InsertTailList(&ContextListHead, &context->ListEntry);
 436
 437     context->magic = 'GLRC';
 438     TRACE("Success!\n");
 439     return (HGLRC)context;
 440 }
 441
 442 HGLRC WINAPI wglCreateLayerContext(HDC hdc, int iLayerPlane)
 443 {
 444     struct wgl_dc_data* dc_data = get_dc_data(hdc);
 445     struct wgl_context* context;
 446     DHGLRC dhglrc;
 447
 448     if(!dc_data)
 449     {
 450         SetLastError(ERROR_INVALID_HANDLE);
 451         return NULL;
 452     }
 453
 454     if(!dc_data->pixelformat)
 455     {
 456         release_dc_data(dc_data);
 457         SetLastError(ERROR_INVALID_PIXEL_FORMAT);
 458         return NULL;
 459     }
 460
 461     if(!dc_data->icd_data)
 462     {
 463         if(iLayerPlane != 0)
 464         {
 465             /* Not supported in SW implementation  */
 466             release_dc_data(dc_data);
 467             SetLastError(ERROR_INVALID_PIXEL_FORMAT);
 468             return NULL;
 469         }
 470         dhglrc = sw_CreateContext(dc_data);
 471     }
 472     else
 473     {
 474         dhglrc = dc_data->icd_data->DrvCreateLayerContext(hdc, iLayerPlane);
 475     }
 476
 477     if(!dhglrc)
 478     {
 479         release_dc_data(dc_data);
 480         SetLastError(ERROR_INVALID_PIXEL_FORMAT);
 481         return NULL;
 482     }
 483
 484     context = HeapAlloc(GetProcessHeap(), 0, sizeof(*context));
 485     if(!context)
 486     {
 487         if(!dc_data->icd_data)
 488             sw_DeleteContext(dhglrc);
 489         else
 490             dc_data->icd_data->DrvDeleteContext(dhglrc);
 491         release_dc_data(dc_data);
 492         SetLastError(ERROR_NOT_ENOUGH_MEMORY);
 493         return NULL;
 494     }
 495     /* Copy info from the DC data */
 496     context->dhglrc = dhglrc;
 497     context->icd_data = dc_data->icd_data;
 498     context->pixelformat = dc_data->pixelformat;
 499     context->thread_id = 0;
 500
 501     context->magic = 'GLRC';
 502
 503     release_dc_data(dc_data);
 504     return (HGLRC)context;
 505 }
 506
 507 BOOL WINAPI wglDeleteContext(HGLRC hglrc)
 508 {
 509     struct wgl_context* context = get_context(hglrc);
 510     LONG thread_id = GetCurrentThreadId();
 511
 512     if(!context)
 513     {
 514         SetLastError(ERROR_INVALID_HANDLE);
 515         return FALSE;
 516     }
 517
 518     /* Own this context before touching it */
 519     if(InterlockedCompareExchange(&context->thread_id, thread_id, 0) != 0)
 520     {
 521         /* We can't delete a context current to another thread */
 522         if(context->thread_id != thread_id)
 523         {
 524             SetLastError(ERROR_BUSY);
 525             return FALSE;
 526         }
 527
 528         /* This is in our thread. Release and try again */
 529         if(!wglMakeCurrent(NULL, NULL))
 530             return FALSE;
 531         return wglDeleteContext(hglrc);
 532     }
 533
 534     if(context->icd_data)
 535         context->icd_data->DrvDeleteContext(context->dhglrc);
 536     else
 537         sw_DeleteContext(context->dhglrc);
 538
 539     context->magic = 0;
 540     RemoveEntryList(&context->ListEntry);
 541     HeapFree(GetProcessHeap(), 0, context);
 542
 543     return TRUE;
 544 }
 545
 546 BOOL WINAPI wglDescribeLayerPlane(HDC hdc,
 547                                   int iPixelFormat,
 548                                   int iLayerPlane,
 549                                   UINT nBytes,
 550                                   LPLAYERPLANEDESCRIPTOR plpd)
 551 {
 552     struct wgl_dc_data* dc_data = get_dc_data(hdc);
 553
 554     if(!dc_data)
 555     {
 556         SetLastError(ERROR_INVALID_HANDLE);
 557         return FALSE;
 558     }
 559
 560     if(iPixelFormat <= dc_data->nb_icd_formats)
 561         return dc_data->icd_data->DrvDescribeLayerPlane(hdc, iPixelFormat, iLayerPlane, nBytes, plpd);
 562
 563     /* SW implementation doesn't support this */
 564     return FALSE;
 565 }
 566
 567 HGLRC WINAPI wglGetCurrentContext(void)
 568 {
 569     return IntGetCurrentRC();
 570 }
 571
 572 HDC WINAPI wglGetCurrentDC(void)
 573 {
 574     return IntGetCurrentDC();
 575 }
 576
 577 PROC WINAPI wglGetDefaultProcAddress(LPCSTR lpszProc)
 578 {
 579     /* undocumented... */
 580     return NULL;
 581 }
 582
 583 int WINAPI wglGetLayerPaletteEntries(HDC hdc, int iLayerPlane, int iStart, int cEntries, COLORREF* pcr )
 584 {
 585     struct wgl_dc_data* dc_data = get_dc_data(hdc);
 586
 587     if(!dc_data)
 588     {
 589         SetLastError(ERROR_INVALID_HANDLE);
 590         return 0;
 591     }
 592
 593     if(!dc_data->pixelformat)
 594     {
 595         SetLastError(ERROR_INVALID_PIXEL_FORMAT);
 596         return 0;
 597     }
 598
 599     if(dc_data->icd_data)
 600         return dc_data->icd_data->DrvGetLayerPaletteEntries(hdc, iLayerPlane, iStart, cEntries, pcr);
 601
 602     /* SW implementation doesn't support this */
 603     return 0;
 604 }
 605
 606 INT WINAPI wglGetPixelFormat(HDC hdc)
 607 {
 608     INT ret;
 609     struct wgl_dc_data* dc_data = get_dc_data(hdc);
 610
 611     if(!dc_data)
 612     {
 613         SetLastError(ERROR_INVALID_HANDLE);
 614         return 0;
 615     }
 616
 617     ret = dc_data->pixelformat;
 618     release_dc_data(dc_data);
 619     return ret;
 620 }
 621
 622 PROC WINAPI wglGetProcAddress(LPCSTR name)
 623 {
 624     struct wgl_context* context = get_context(IntGetCurrentRC());
 625     if(!context)
 626         return NULL;
 627
 628     /* This shall fail for opengl 1.1 functions */
 629 #define USE_GL_FUNC(func, w, x, y, z) if(!strcmp(name, "gl" #func)) return NULL;
 630 #include "glfuncs.h"
 631
 632     /* Forward */
 633     if(context->icd_data)
 634         return context->icd_data->DrvGetProcAddress(name);
 635     return sw_GetProcAddress(name);
 636 }
 637
 638 void APIENTRY set_api_table(const GLCLTPROCTABLE* table)
 639 {
 640     IntSetCurrentDispatchTable(&table->glDispatchTable);
 641 }
 642
 643 BOOL WINAPI wglMakeCurrent(HDC hdc, HGLRC hglrc)
 644 {
 645     struct wgl_context* ctx = get_context(hglrc);
 646     struct wgl_context* old_ctx = get_context(IntGetCurrentRC());
 647     const GLCLTPROCTABLE* apiTable;
 648     LONG thread_id = (LONG)GetCurrentThreadId();
 649
 650     if(ctx)
 651     {
 652         struct wgl_dc_data* dc_data = get_dc_data(hdc);
 653         if(!dc_data)
 654         {
 655             ERR("wglMakeCurrent was passed an invalid DC handle.\n");
 656             SetLastError(ERROR_INVALID_HANDLE);
 657             return FALSE;
 658         }
 659
 660         /* Check compatibility */
 661         if((ctx->icd_data != dc_data->icd_data) || (ctx->pixelformat != dc_data->pixelformat))
 662         {
 663             /* That's bad, man */
 664             ERR("HGLRC %p and HDC %p are not compatible.\n", hglrc, hdc);
 665             release_dc_data(dc_data);
 666             SetLastError(ERROR_INVALID_HANDLE);
 667             return FALSE;
 668         }
 669
 670         /* Set the thread ID */
 671         if(InterlockedCompareExchange(&ctx->thread_id, thread_id, 0) != 0)
 672         {
 673             /* Already current for a thread. Maybe it's us ? */
 674             release_dc_data(dc_data);
 675             if(ctx->thread_id != thread_id)
 676                 SetLastError(ERROR_BUSY);
 677             return (ctx->thread_id == thread_id);
 678         }
 679
 680         if(old_ctx)
 681         {
 682             /* Unset it */
 683             if(old_ctx->icd_data)
 684                 old_ctx->icd_data->DrvReleaseContext(old_ctx->dhglrc);
 685             else
 686                 sw_ReleaseContext(old_ctx->dhglrc);
 687             InterlockedExchange(&old_ctx->thread_id, 0);
 688         }
 689
 690         /* Call the ICD or SW implementation */
 691         if(ctx->icd_data)
 692         {
 693             apiTable = ctx->icd_data->DrvSetContext(hdc, ctx->dhglrc, set_api_table);
 694             if(!apiTable)
 695             {
 696                 ERR("DrvSetContext failed!\n");
 697                 /* revert */
 698                 InterlockedExchange(&ctx->thread_id, 0);
 699                 IntSetCurrentDispatchTable(NULL);
 700                 SetLastError(ERROR_INVALID_PARAMETER);
 701                 return FALSE;
 702             }
 703             set_api_table(apiTable);
 704             /* Make it current */
 705             IntMakeCurrent(hglrc, hdc, dc_data);
 706         }
 707         else
 708         {
 709             /* We must set current before, SW implementation relies on it */
 710             IntMakeCurrent(hglrc, hdc, dc_data);
 711             if(!sw_SetContext(dc_data, ctx->dhglrc))
 712             {
 713                 ERR("sw_SetContext failed!\n");
 714                 /* revert */
 715                 IntMakeCurrent(NULL, NULL, NULL);
 716                 InterlockedExchange(&ctx->thread_id, 0);
 717                 SetLastError(ERROR_INVALID_PARAMETER);
 718                 return FALSE;
 719             }
 720         }
 721     }
 722     else if(old_ctx)
 723     {
 724         if(old_ctx->icd_data)
 725             old_ctx->icd_data->DrvReleaseContext(old_ctx->dhglrc);
 726         else
 727             sw_ReleaseContext(old_ctx->dhglrc);
 728         InterlockedExchange(&old_ctx->thread_id, 0);
 729         /* Unset it */
 730         IntMakeCurrent(NULL, NULL, NULL);
 731         IntSetCurrentDispatchTable(NULL);
 732         /* Test conformance (extreme cases) */
 733         return hglrc == NULL;
 734     }
 735     else
 736     {
 737         /* Winetest conformance */
 738         if (GetObjectType( hdc ) != OBJ_DC && GetObjectType( hdc ) != OBJ_MEMDC)
 739         {
 740             ERR( "Error: hdc is not a DC handle!\n");
 741             SetLastError( ERROR_INVALID_HANDLE );
 742             return FALSE;
 743         }
 744     }
 745
 746     return TRUE;
 747 }
 748
 749 BOOL WINAPI wglRealizeLayerPalette(HDC hdc,
 750                                    int iLayerPlane,
 751                                    BOOL bRealize)
 752 {
 753     struct wgl_dc_data* dc_data = get_dc_data(hdc);
 754
 755     if(!dc_data)
 756     {
 757         SetLastError(ERROR_INVALID_HANDLE);
 758         return FALSE;
 759     }
 760
 761     if(!dc_data->pixelformat)
 762     {
 763         SetLastError(ERROR_INVALID_PIXEL_FORMAT);
 764         return FALSE;
 765     }
 766
 767     if(dc_data->icd_data)
 768         return dc_data->icd_data->DrvRealizeLayerPalette(hdc, iLayerPlane, bRealize);
 769
 770     /* SW implementation doesn't support this */
 771     return FALSE;
 772 }
 773
 774 int WINAPI wglSetLayerPaletteEntries(HDC hdc,
 775                                      int iLayerPlane,
 776                                      int iStart,
 777                                      int cEntries,
 778                                      const COLORREF *pcr)
 779 {
 780     struct wgl_dc_data* dc_data = get_dc_data(hdc);
 781
 782     if(!dc_data)
 783     {
 784         SetLastError(ERROR_INVALID_HANDLE);
 785         return 0;
 786     }
 787
 788     if(!dc_data->pixelformat)
 789     {
 790         SetLastError(ERROR_INVALID_PIXEL_FORMAT);
 791         return 0;
 792     }
 793
 794     if(dc_data->icd_data)
 795         return dc_data->icd_data->DrvSetLayerPaletteEntries(hdc, iLayerPlane, iStart, cEntries, pcr);
 796
 797     /* SW implementation doesn't support this */
 798     return 0;
 799 }
 800
 801 BOOL WINAPI wglSetPixelFormat(HDC hdc, INT format, const PIXELFORMATDESCRIPTOR *descr)
 802 {
 803     struct wgl_dc_data* dc_data = get_dc_data(hdc);
 804     INT sw_format;
 805     BOOL ret;
 806
 807     TRACE("HDC %p, format %i.\n", hdc, format);
 808
 809     if(!dc_data)
 810     {
 811         WARN("Not a valid DC!.\n");
 812         SetLastError(ERROR_INVALID_HANDLE);
 813         return FALSE;
 814     }
 815
 816     if(!format)
 817     {
 818         WARN("format == 0!\n");
 819         SetLastError(ERROR_INVALID_PARAMETER);
 820         return FALSE;
 821     }
 822
 823     if(dc_data->pixelformat)
 824     {
 825         TRACE("DC format already set, %i.\n", dc_data->pixelformat);
 826         return (format == dc_data->pixelformat);
 827     }
 828
 829     if(format <= dc_data->nb_icd_formats)
 830     {
 831         TRACE("Calling ICD.\n");
 832         ret = dc_data->icd_data->DrvSetPixelFormat(hdc, format);
 833         if(ret)
 834         {
 835             TRACE("Success!\n");
 836             dc_data->pixelformat = format;
 837         }
 838         return ret;
 839     }
 840
 841     sw_format = format - dc_data->nb_icd_formats;
 842     if(sw_format <= dc_data->nb_sw_formats)
 843     {
 844         TRACE("Calling SW implementation.\n");
 845         ret = sw_SetPixelFormat(hdc, dc_data, sw_format);
 846         if(ret)
 847         {
 848             TRACE("Success!\n");
 849             /* This is now officially a software-only HDC */
 850             dc_data->icd_data = NULL;
 851             dc_data->pixelformat = format;
 852         }
 853         return ret;
 854     }
 855
 856     TRACE("Invalid pixel format!\n");
 857     SetLastError(ERROR_INVALID_PARAMETER);
 858     return FALSE;
 859 }
 860
 861 BOOL WINAPI wglShareLists(HGLRC hglrcSrc, HGLRC hglrcDst)
 862 {
 863     struct wgl_context* ctx_src = get_context(hglrcSrc);
 864     struct wgl_context* ctx_dst = get_context(hglrcDst);
 865
 866     if(!ctx_src || !ctx_dst)
 867     {
 868         SetLastError(ERROR_INVALID_HANDLE);
 869         return FALSE;
 870     }
 871
 872     /* Check this is the same pixel format */
 873     if((ctx_dst->icd_data != ctx_src->icd_data) ||
 874         (ctx_dst->pixelformat != ctx_src->pixelformat))
 875     {
 876         SetLastError(ERROR_INVALID_PIXEL_FORMAT);
 877         return FALSE;
 878     }
 879
 880     if(ctx_src->icd_data)
 881         return ctx_src->icd_data->DrvShareLists(ctx_src->dhglrc, ctx_dst->dhglrc);
 882
 883     return sw_ShareLists(ctx_src->dhglrc, ctx_dst->dhglrc);
 884 }
 885
 886 BOOL WINAPI DECLSPEC_HOTPATCH wglSwapBuffers(HDC hdc)
 887 {
 888     struct wgl_dc_data* dc_data = get_dc_data(hdc);
 889
 890     if(!dc_data)
 891     {
 892         SetLastError(ERROR_INVALID_HANDLE);
 893         return FALSE;
 894     }
 895
 896     if(!dc_data->pixelformat)
 897     {
 898         SetLastError(ERROR_INVALID_PIXEL_FORMAT);
 899         return FALSE;
 900     }
 901
 902     if(dc_data->icd_data)
 903         return dc_data->icd_data->DrvSwapBuffers(hdc);
 904
 905     return sw_SwapBuffers(hdc, dc_data);
 906 }
 907
 908 BOOL WINAPI wglSwapLayerBuffers(HDC hdc, UINT fuPlanes)
 909 {
 910     return FALSE;
 911 }
 912
 913 DWORD WINAPI wglSwapMultipleBuffers(UINT count, CONST WGLSWAP * toSwap)
 914 {
 915     return 0;
 916 }
 917
 918 /* Clean up on DLL unload */
 919 void
 920 IntDeleteAllContexts(void)
 921 {
 922     struct wgl_context* context;
 923     LIST_ENTRY* Entry = ContextListHead.Flink;
 924
 925     while (Entry != &ContextListHead)
 926     {
 927         context = CONTAINING_RECORD(Entry, struct wgl_context, ListEntry);
 928         wglDeleteContext((HGLRC)context);
 929         Entry = Entry->Flink;
 930     }
 931 }