dlls/gdi/bitmap.c

   1 /*
   2  * GDI bitmap objects
   3  *
   4  * Copyright 1993 Alexandre Julliard
   5  *           1998 Huw D M Davies
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include <stdlib.h>
  23 #include <string.h>
  24
  25 #include "wine/winbase16.h"
  26 #include "wine/wingdi16.h"
  27 #include "gdi.h"
  28 #include "gdi_private.h"
  29 #include "wine/debug.h"
  30
  31 WINE_DEFAULT_DEBUG_CHANNEL(bitmap);
  32
  33
  34 static HGDIOBJ BITMAP_SelectObject( HGDIOBJ handle, void *obj, HDC hdc );
  35 static INT BITMAP_GetObject16( HGDIOBJ handle, void *obj, INT count, LPVOID buffer );
  36 static INT BITMAP_GetObject( HGDIOBJ handle, void *obj, INT count, LPVOID buffer );
  37 static BOOL BITMAP_DeleteObject( HGDIOBJ handle, void *obj );
  38
  39 static const struct gdi_obj_funcs bitmap_funcs =
  40 {
  41     BITMAP_SelectObject,  /* pSelectObject */
  42     BITMAP_GetObject16,   /* pGetObject16 */
  43     BITMAP_GetObject,     /* pGetObjectA */
  44     BITMAP_GetObject,     /* pGetObjectW */
  45     NULL,                 /* pUnrealizeObject */
  46     BITMAP_DeleteObject   /* pDeleteObject */
  47 };
  48
  49 /***********************************************************************
  50  *           BITMAP_GetWidthBytes
  51  *
  52  * Return number of bytes taken by a scanline of 16-bit aligned Windows DDB
  53  * data.
  54  */
  55 INT BITMAP_GetWidthBytes( INT bmWidth, INT bpp )
  56 {
  57     switch(bpp)
  58     {
  59     case 1:
  60         return 2 * ((bmWidth+15) >> 4);
  61
  62     case 24:
  63         bmWidth *= 3; /* fall through */
  64     case 8:
  65         return bmWidth + (bmWidth & 1);
  66
  67     case 32:
  68         return bmWidth * 4;
  69
  70     case 16:
  71     case 15:
  72         return bmWidth * 2;
  73
  74     case 4:
  75         return 2 * ((bmWidth+3) >> 2);
  76
  77     default:
  78         WARN("Unknown depth %d, please report.\n", bpp );
  79     }
  80     return -1;
  81 }
  82
  83
  84 /******************************************************************************
  85  * CreateBitmap [GDI32.@]
  86  *
  87  * Creates a bitmap with the specified info.
  88  *
  89  * PARAMS
  90  *    width  [I] bitmap width
  91  *    height [I] bitmap height
  92  *    planes [I] Number of color planes
  93  *    bpp    [I] Number of bits to identify a color
  94  *    bits   [I] Pointer to array containing color data
  95  *
  96  * RETURNS
  97  *    Success: Handle to bitmap
  98  *    Failure: 0
  99  */
 100 HBITMAP WINAPI CreateBitmap( INT width, INT height, UINT planes,
 101                              UINT bpp, LPCVOID bits )
 102 {
 103     BITMAP bm;
 104
 105     bm.bmType = 0;
 106     bm.bmWidth = width;
 107     bm.bmHeight = height;
 108     bm.bmWidthBytes = BITMAP_GetWidthBytes( width, bpp );
 109     bm.bmPlanes = planes;
 110     bm.bmBitsPixel = bpp;
 111     bm.bmBits = (LPVOID)bits;
 112
 113     return CreateBitmapIndirect( &bm );
 114 }
 115
 116 /******************************************************************************
 117  * CreateCompatibleBitmap [GDI32.@]
 118  *
 119  * Creates a bitmap compatible with the DC.
 120  *
 121  * PARAMS
 122  *    hdc    [I] Handle to device context
 123  *    width  [I] Width of bitmap
 124  *    height [I] Height of bitmap
 125  *
 126  * RETURNS
 127  *    Success: Handle to bitmap
 128  *    Failure: 0
 129  */
 130 HBITMAP WINAPI CreateCompatibleBitmap( HDC hdc, INT width, INT height)
 131 {
 132     HBITMAP hbmpRet = 0;
 133     DC *dc;
 134
 135     TRACE("(%p,%d,%d) =\n", hdc, width, height);
 136
 137     if ((width >= 0x10000) || (height >= 0x10000))
 138     {
 139         FIXME("got bad width %d or height %d, please look for reason\n",
 140               width, height);
 141     }
 142     else
 143     {
 144         if (!(dc = DC_GetDCPtr(hdc))) return 0;
 145
 146         if (GDIMAGIC( dc->header.wMagic ) != MEMORY_DC_MAGIC)
 147         {
 148             hbmpRet = CreateBitmap(width, height,
 149                                    GetDeviceCaps(hdc, PLANES),
 150                                    GetDeviceCaps(hdc, BITSPIXEL),
 151                                    NULL);
 152         }
 153         else  /* Memory DC */
 154         {
 155             BITMAPOBJ *bmp = GDI_GetObjPtr( dc->hBitmap, BITMAP_MAGIC );
 156
 157             if (!bmp->dib)
 158             {
 159                 /* A device-dependent bitmap is selected in the DC */
 160                 hbmpRet = CreateBitmap(width, height,
 161                                        bmp->bitmap.bmPlanes,
 162                                        bmp->bitmap.bmBitsPixel,
 163                                        NULL);
 164             }
 165             else
 166             {
 167                 /* A DIB section is selected in the DC */
 168                 BITMAPINFO *bi;
 169                 void *bits;
 170
 171                 /* Allocate memory for a BITMAPINFOHEADER structure and a
 172                    color table. The maximum number of colors in a color table
 173                    is 256 which corresponds to a bitmap with depth 8.
 174                    Bitmaps with higher depths don't have color tables. */
 175                 bi = HeapAlloc(GetProcessHeap(), 0, sizeof(BITMAPINFOHEADER) + 256 * sizeof(RGBQUAD));
 176
 177                 if (bi)
 178                 {
 179                     bi->bmiHeader.biSize          = sizeof(bi->bmiHeader);
 180                     bi->bmiHeader.biWidth         = width;
 181                     bi->bmiHeader.biHeight        = height;
 182                     bi->bmiHeader.biPlanes        = bmp->dib->dsBmih.biPlanes;
 183                     bi->bmiHeader.biBitCount      = bmp->dib->dsBmih.biBitCount;
 184                     bi->bmiHeader.biCompression   = bmp->dib->dsBmih.biCompression;
 185                     bi->bmiHeader.biSizeImage     = 0;
 186                     bi->bmiHeader.biXPelsPerMeter = bmp->dib->dsBmih.biXPelsPerMeter;
 187                     bi->bmiHeader.biYPelsPerMeter = bmp->dib->dsBmih.biYPelsPerMeter;
 188                     bi->bmiHeader.biClrUsed       = bmp->dib->dsBmih.biClrUsed;
 189                     bi->bmiHeader.biClrImportant  = bmp->dib->dsBmih.biClrImportant;
 190
 191                     if (bi->bmiHeader.biCompression == BI_BITFIELDS)
 192                     {
 193                         /* Copy the color masks */
 194                         CopyMemory(bi->bmiColors, bmp->dib->dsBitfields, 3 * sizeof(DWORD));
 195                     }
 196                     else if (bi->bmiHeader.biBitCount <= 8)
 197                     {
 198                         /* Copy the color table */
 199                         GetDIBColorTable(hdc, 0, 256, bi->bmiColors);
 200                     }
 201
 202                     hbmpRet = CreateDIBSection(hdc, bi, DIB_RGB_COLORS, &bits, NULL, 0);
 203                     HeapFree(GetProcessHeap(), 0, bi);
 204                 }
 205             }
 206             GDI_ReleaseObj(dc->hBitmap);
 207         }
 208         GDI_ReleaseObj(hdc);
 209     }
 210
 211     TRACE("\t\t%p\n", hbmpRet);
 212     return hbmpRet;
 213 }
 214
 215
 216 /******************************************************************************
 217  * CreateBitmapIndirect [GDI32.@]
 218  *
 219  * Creates a bitmap with the specified info.
 220  *
 221  * PARAMS
 222  *  bmp [I] Pointer to the bitmap info describing the bitmap
 223  *
 224  * RETURNS
 225  *    Success: Handle to bitmap
 226  *    Failure: NULL. Use GetLastError() to determine the cause.
 227  *
 228  * NOTES
 229  *  If a width or height of 0 are given, a 1x1 monochrome bitmap is returned.
 230  */
 231 HBITMAP WINAPI CreateBitmapIndirect( const BITMAP *bmp )
 232 {
 233     BITMAP bm;
 234     BITMAPOBJ *bmpobj;
 235     HBITMAP hbitmap;
 236
 237     if (!bmp || bmp->bmType || bmp->bmPlanes != 1)
 238     {
 239         if (bmp && bmp->bmPlanes != 1)
 240             FIXME("planes = %d\n", bmp->bmPlanes);
 241         SetLastError( ERROR_INVALID_PARAMETER );
 242         return NULL;
 243     }
 244
 245     bm = *bmp;
 246
 247     if (!bm.bmWidth || !bm.bmHeight)
 248     {
 249         bm.bmWidth = bm.bmHeight = 1;
 250         bm.bmPlanes = bm.bmBitsPixel = 1;
 251         bm.bmWidthBytes = 2;
 252         bm.bmBits = NULL;
 253     }
 254     else
 255     {
 256         if (bm.bmHeight < 0)
 257             bm.bmHeight = -bm.bmHeight;
 258         if (bm.bmWidth < 0)
 259             bm.bmWidth = -bm.bmWidth;
 260     }
 261
 262       /* Create the BITMAPOBJ */
 263     bmpobj = GDI_AllocObject( sizeof(BITMAPOBJ), BITMAP_MAGIC,
 264                               (HGDIOBJ *)&hbitmap, &bitmap_funcs );
 265
 266     if (!bmpobj)
 267     {
 268         SetLastError( ERROR_NOT_ENOUGH_MEMORY );
 269         return NULL;
 270     }
 271
 272     TRACE("%dx%d, %d colors returning %p\n", bm.bmWidth, bm.bmHeight,
 273           1 << (bm.bmPlanes * bm.bmBitsPixel), hbitmap);
 274
 275     bmpobj->size.cx = 0;
 276     bmpobj->size.cy = 0;
 277     bmpobj->bitmap = bm;
 278     bmpobj->bitmap.bmBits = NULL;
 279     bmpobj->funcs = NULL;
 280     bmpobj->dib = NULL;
 281     bmpobj->segptr_bits = 0;
 282
 283     if (bm.bmBits)
 284         SetBitmapBits( hbitmap, bm.bmHeight * bm.bmWidthBytes, bm.bmBits );
 285
 286     GDI_ReleaseObj( hbitmap );
 287     return hbitmap;
 288 }
 289
 290
 291 /***********************************************************************
 292  * GetBitmapBits [GDI32.@]
 293  *
 294  * Copies bitmap bits of bitmap to buffer.
 295  *
 296  * RETURNS
 297  *    Success: Number of bytes copied
 298  *    Failure: 0
 299  */
 300 LONG WINAPI GetBitmapBits(
 301     HBITMAP hbitmap, /* [in]  Handle to bitmap */
 302     LONG count,        /* [in]  Number of bytes to copy */
 303     LPVOID bits)       /* [out] Pointer to buffer to receive bits */
 304 {
 305     BITMAPOBJ *bmp = (BITMAPOBJ *) GDI_GetObjPtr( hbitmap, BITMAP_MAGIC );
 306     LONG height, ret;
 307
 308     if (!bmp) return 0;
 309
 310     if (bmp->dib)  /* simply copy the bits from the DIB */
 311     {
 312         DIBSECTION *dib = bmp->dib;
 313         const char *src = dib->dsBm.bmBits;
 314         DWORD max = dib->dsBm.bmWidthBytes * dib->dsBm.bmHeight;
 315         if (count > max) count = max;
 316         ret = count;
 317         if (!bits) goto done;
 318
 319         if (bmp->dib->dsBmih.biHeight >= 0)  /* not top-down, need to flip contents vertically */
 320         {
 321             src += dib->dsBm.bmWidthBytes * dib->dsBm.bmHeight;
 322             while (count > 0)
 323             {
 324                 src -= dib->dsBm.bmWidthBytes;
 325                 memcpy( bits, src, min( count, dib->dsBm.bmWidthBytes ) );
 326                 bits = (char *)bits + dib->dsBm.bmWidthBytes;
 327                 count -= dib->dsBm.bmWidthBytes;
 328             }
 329         }
 330         else memcpy( bits, src, count );
 331         goto done;
 332     }
 333
 334     /* If the bits vector is null, the function should return the read size */
 335     if(bits == NULL)
 336     {
 337         ret = bmp->bitmap.bmWidthBytes * bmp->bitmap.bmHeight;
 338         goto done;
 339     }
 340
 341     if (count < 0) {
 342         WARN("(%ld): Negative number of bytes passed???\n", count );
 343         count = -count;
 344     }
 345
 346     /* Only get entire lines */
 347     height = count / bmp->bitmap.bmWidthBytes;
 348     if (height > bmp->bitmap.bmHeight) height = bmp->bitmap.bmHeight;
 349     count = height * bmp->bitmap.bmWidthBytes;
 350     if (count == 0)
 351       {
 352         WARN("Less than one entire line requested\n");
 353         ret = 0;
 354         goto done;
 355       }
 356
 357
 358     TRACE("(%p, %ld, %p) %dx%d %d colors fetched height: %ld\n",
 359           hbitmap, count, bits, bmp->bitmap.bmWidth, bmp->bitmap.bmHeight,
 360           1 << bmp->bitmap.bmBitsPixel, height );
 361
 362     if(bmp->funcs && bmp->funcs->pGetBitmapBits)
 363     {
 364         TRACE("Calling device specific BitmapBits\n");
 365         ret = bmp->funcs->pGetBitmapBits(hbitmap, bits, count);
 366     } else {
 367
 368         if(!bmp->bitmap.bmBits) {
 369             WARN("Bitmap is empty\n");
 370             ret = 0;
 371         } else {
 372             memcpy(bits, bmp->bitmap.bmBits, count);
 373             ret = count;
 374         }
 375
 376     }
 377  done:
 378     GDI_ReleaseObj( hbitmap );
 379     return ret;
 380 }
 381
 382
 383 /******************************************************************************
 384  * SetBitmapBits [GDI32.@]
 385  *
 386  * Sets bits of color data for a bitmap.
 387  *
 388  * RETURNS
 389  *    Success: Number of bytes used in setting the bitmap bits
 390  *    Failure: 0
 391  */
 392 LONG WINAPI SetBitmapBits(
 393     HBITMAP hbitmap, /* [in] Handle to bitmap */
 394     LONG count,        /* [in] Number of bytes in bitmap array */
 395     LPCVOID bits)      /* [in] Address of array with bitmap bits */
 396 {
 397     BITMAPOBJ *bmp = (BITMAPOBJ *) GDI_GetObjPtr( hbitmap, BITMAP_MAGIC );
 398     LONG height, ret;
 399
 400     if ((!bmp) || (!bits))
 401         return 0;
 402
 403     if (count < 0) {
 404         WARN("(%ld): Negative number of bytes passed???\n", count );
 405         count = -count;
 406     }
 407
 408     if (bmp->dib)  /* simply copy the bits into the DIB */
 409     {
 410         DIBSECTION *dib = bmp->dib;
 411         char *dest = dib->dsBm.bmBits;
 412         DWORD max = dib->dsBm.bmWidthBytes * dib->dsBm.bmHeight;
 413         if (count > max) count = max;
 414         ret = count;
 415
 416         if (bmp->dib->dsBmih.biHeight >= 0)  /* not top-down, need to flip contents vertically */
 417         {
 418             dest += dib->dsBm.bmWidthBytes * dib->dsBm.bmHeight;
 419             while (count > 0)
 420             {
 421                 dest -= dib->dsBm.bmWidthBytes;
 422                 memcpy( dest, bits, min( count, dib->dsBm.bmWidthBytes ) );
 423                 bits = (char *)bits + dib->dsBm.bmWidthBytes;
 424                 count -= dib->dsBm.bmWidthBytes;
 425             }
 426         }
 427         else memcpy( dest, bits, count );
 428
 429         GDI_ReleaseObj( hbitmap );
 430         return ret;
 431     }
 432
 433     /* Only get entire lines */
 434     height = count / bmp->bitmap.bmWidthBytes;
 435     if (height > bmp->bitmap.bmHeight) height = bmp->bitmap.bmHeight;
 436     count = height * bmp->bitmap.bmWidthBytes;
 437
 438     TRACE("(%p, %ld, %p) %dx%d %d colors fetched height: %ld\n",
 439           hbitmap, count, bits, bmp->bitmap.bmWidth, bmp->bitmap.bmHeight,
 440           1 << bmp->bitmap.bmBitsPixel, height );
 441
 442     if(bmp->funcs && bmp->funcs->pSetBitmapBits) {
 443
 444         TRACE("Calling device specific BitmapBits\n");
 445         ret = bmp->funcs->pSetBitmapBits(hbitmap, bits, count);
 446     } else {
 447
 448         if(!bmp->bitmap.bmBits) /* Alloc enough for entire bitmap */
 449             bmp->bitmap.bmBits = HeapAlloc( GetProcessHeap(), 0, count );
 450         if(!bmp->bitmap.bmBits) {
 451             WARN("Unable to allocate bit buffer\n");
 452             ret = 0;
 453         } else {
 454             memcpy(bmp->bitmap.bmBits, bits, count);
 455             ret = count;
 456         }
 457     }
 458
 459     GDI_ReleaseObj( hbitmap );
 460     return ret;
 461 }
 462
 463 /**********************************************************************
 464  *              BITMAP_CopyBitmap
 465  *
 466  */
 467 HBITMAP BITMAP_CopyBitmap(HBITMAP hbitmap)
 468 {
 469     BITMAPOBJ *bmp = (BITMAPOBJ *) GDI_GetObjPtr( hbitmap, BITMAP_MAGIC );
 470     HBITMAP res = 0;
 471     BITMAP bm;
 472
 473     if(!bmp) return 0;
 474
 475     bm = bmp->bitmap;
 476     bm.bmBits = NULL;
 477     res = CreateBitmapIndirect(&bm);
 478
 479     if(res) {
 480         char *buf = HeapAlloc( GetProcessHeap(), 0, bm.bmWidthBytes *
 481                                bm.bmHeight );
 482         GetBitmapBits (hbitmap, bm.bmWidthBytes * bm.bmHeight, buf);
 483         SetBitmapBits (res, bm.bmWidthBytes * bm.bmHeight, buf);
 484         HeapFree( GetProcessHeap(), 0, buf );
 485     }
 486
 487     GDI_ReleaseObj( hbitmap );
 488     return res;
 489 }
 490
 491
 492 /***********************************************************************
 493  *           BITMAP_SetOwnerDC
 494  *
 495  * Set the type of DC that owns the bitmap. This is used when the
 496  * bitmap is selected into a device to initialize the bitmap function
 497  * table.
 498  */
 499 BOOL BITMAP_SetOwnerDC( HBITMAP hbitmap, DC *dc )
 500 {
 501     BITMAPOBJ *bitmap;
 502     BOOL ret;
 503
 504     /* never set the owner of the stock bitmap since it can be selected in multiple DCs */
 505     if (hbitmap == GetStockObject(DEFAULT_BITMAP)) return TRUE;
 506
 507     if (!(bitmap = GDI_GetObjPtr( hbitmap, BITMAP_MAGIC ))) return FALSE;
 508
 509     ret = TRUE;
 510     if (!bitmap->funcs)  /* not owned by a DC yet */
 511     {
 512         if (dc->funcs->pCreateBitmap) ret = dc->funcs->pCreateBitmap( dc->physDev, hbitmap );
 513         if (ret) bitmap->funcs = dc->funcs;
 514     }
 515     else if (bitmap->funcs != dc->funcs)
 516     {
 517         FIXME( "Trying to select bitmap %p in different DC type\n", hbitmap );
 518         ret = FALSE;
 519     }
 520     GDI_ReleaseObj( hbitmap );
 521     return ret;
 522 }
 523
 524
 525 /***********************************************************************
 526  *           BITMAP_SelectObject
 527  */
 528 static HGDIOBJ BITMAP_SelectObject( HGDIOBJ handle, void *obj, HDC hdc )
 529 {
 530     HGDIOBJ ret;
 531     BITMAPOBJ *bitmap = obj;
 532     DC *dc = DC_GetDCPtr( hdc );
 533
 534     if (!dc) return 0;
 535     if (GetObjectType( hdc ) != OBJ_MEMDC)
 536     {
 537         GDI_ReleaseObj( hdc );
 538         return 0;
 539     }
 540     ret = dc->hBitmap;
 541     if (handle == dc->hBitmap) goto done;  /* nothing to do */
 542
 543     if (bitmap->header.dwCount && (handle != GetStockObject(DEFAULT_BITMAP)))
 544     {
 545         WARN( "Bitmap already selected in another DC\n" );
 546         GDI_ReleaseObj( hdc );
 547         return 0;
 548     }
 549
 550     if (!bitmap->funcs && !BITMAP_SetOwnerDC( handle, dc ))
 551     {
 552         GDI_ReleaseObj( hdc );
 553         return 0;
 554     }
 555
 556     if (dc->funcs->pSelectBitmap) handle = dc->funcs->pSelectBitmap( dc->physDev, handle );
 557
 558     if (handle)
 559     {
 560         dc->hBitmap = handle;
 561         dc->flags &= ~DC_DIRTY;
 562         SetRectRgn( dc->hVisRgn, 0, 0, bitmap->bitmap.bmWidth, bitmap->bitmap.bmHeight);
 563         DC_InitDC( dc );
 564     }
 565     else ret = 0;
 566
 567  done:
 568     GDI_ReleaseObj( hdc );
 569     return ret;
 570 }
 571
 572
 573 /***********************************************************************
 574  *           BITMAP_DeleteObject
 575  */
 576 static BOOL BITMAP_DeleteObject( HGDIOBJ handle, void *obj )
 577 {
 578     BITMAPOBJ * bmp = obj;
 579
 580     if (bmp->funcs && bmp->funcs->pDeleteBitmap)
 581         bmp->funcs->pDeleteBitmap( handle );
 582
 583     HeapFree( GetProcessHeap(), 0, bmp->bitmap.bmBits );
 584
 585     if (bmp->dib)
 586     {
 587         DIBSECTION *dib = bmp->dib;
 588
 589         if (dib->dsBm.bmBits)
 590         {
 591             if (dib->dshSection)
 592             {
 593                 SYSTEM_INFO SystemInfo;
 594                 GetSystemInfo( &SystemInfo );
 595                 UnmapViewOfFile( (char *)dib->dsBm.bmBits -
 596                                  (dib->dsOffset % SystemInfo.dwAllocationGranularity) );
 597             }
 598             else if (!dib->dsOffset)
 599                 VirtualFree(dib->dsBm.bmBits, 0L, MEM_RELEASE );
 600         }
 601         HeapFree(GetProcessHeap(), 0, dib);
 602         bmp->dib = NULL;
 603         if (bmp->segptr_bits)
 604         { /* free its selector array */
 605             WORD sel = SELECTOROF(bmp->segptr_bits);
 606             WORD count = (GetSelectorLimit16(sel) / 0x10000) + 1;
 607             int i;
 608
 609             for (i = 0; i < count; i++) FreeSelector16(sel + (i << __AHSHIFT));
 610         }
 611     }
 612     return GDI_FreeObject( handle, obj );
 613 }
 614
 615
 616 /***********************************************************************
 617  *           BITMAP_GetObject16
 618  */
 619 static INT BITMAP_GetObject16( HGDIOBJ handle, void *obj, INT count, LPVOID buffer )
 620 {
 621     BITMAPOBJ *bmp = obj;
 622
 623     if (bmp->dib)
 624     {
 625         if ( count <= sizeof(BITMAP16) )
 626         {
 627             BITMAP *bmp32 = &bmp->dib->dsBm;
 628             BITMAP16 bmp16;
 629             bmp16.bmType       = bmp32->bmType;
 630             bmp16.bmWidth      = bmp32->bmWidth;
 631             bmp16.bmHeight     = bmp32->bmHeight;
 632             bmp16.bmWidthBytes = bmp32->bmWidthBytes;
 633             bmp16.bmPlanes     = bmp32->bmPlanes;
 634             bmp16.bmBitsPixel  = bmp32->bmBitsPixel;
 635             bmp16.bmBits       = (SEGPTR)0;
 636             memcpy( buffer, &bmp16, count );
 637             return count;
 638         }
 639         else
 640         {
 641             FIXME("not implemented for DIBs: count %d\n", count);
 642             return 0;
 643         }
 644     }
 645     else
 646     {
 647         BITMAP16 bmp16;
 648         bmp16.bmType       = bmp->bitmap.bmType;
 649         bmp16.bmWidth      = bmp->bitmap.bmWidth;
 650         bmp16.bmHeight     = bmp->bitmap.bmHeight;
 651         bmp16.bmWidthBytes = bmp->bitmap.bmWidthBytes;
 652         bmp16.bmPlanes     = bmp->bitmap.bmPlanes;
 653         bmp16.bmBitsPixel  = bmp->bitmap.bmBitsPixel;
 654         bmp16.bmBits       = (SEGPTR)0;
 655         if (count > sizeof(bmp16)) count = sizeof(bmp16);
 656         memcpy( buffer, &bmp16, count );
 657         return count;
 658     }
 659 }
 660
 661
 662 /***********************************************************************
 663  *           BITMAP_GetObject
 664  */
 665 static INT BITMAP_GetObject( HGDIOBJ handle, void *obj, INT count, LPVOID buffer )
 666 {
 667     BITMAPOBJ *bmp = obj;
 668
 669     if (bmp->dib)
 670     {
 671         if( !buffer )
 672             return sizeof(DIBSECTION);
 673         if (count < sizeof(DIBSECTION))
 674         {
 675             if (count > sizeof(BITMAP)) count = sizeof(BITMAP);
 676         }
 677         else
 678         {
 679             if (count > sizeof(DIBSECTION)) count = sizeof(DIBSECTION);
 680         }
 681
 682         memcpy( buffer, bmp->dib, count );
 683         return count;
 684     }
 685     else
 686     {
 687         if( !buffer )
 688             return sizeof(BITMAP);
 689         if (count > sizeof(BITMAP)) count = sizeof(BITMAP);
 690         memcpy( buffer, &bmp->bitmap, count );
 691         return count;
 692     }
 693 }
 694
 695
 696 /******************************************************************************
 697  * CreateDiscardableBitmap [GDI32.@]
 698  *
 699  * Creates a discardable bitmap.
 700  *
 701  * RETURNS
 702  *    Success: Handle to bitmap
 703  *    Failure: NULL
 704  */
 705 HBITMAP WINAPI CreateDiscardableBitmap(
 706     HDC hdc,    /* [in] Handle to device context */
 707     INT width,  /* [in] Bitmap width */
 708     INT height) /* [in] Bitmap height */
 709 {
 710     return CreateCompatibleBitmap( hdc, width, height );
 711 }
 712
 713
 714 /******************************************************************************
 715  * GetBitmapDimensionEx [GDI32.@]
 716  *
 717  * Retrieves dimensions of a bitmap.
 718  *
 719  * RETURNS
 720  *    Success: TRUE
 721  *    Failure: FALSE
 722  */
 723 BOOL WINAPI GetBitmapDimensionEx(
 724     HBITMAP hbitmap, /* [in]  Handle to bitmap */
 725     LPSIZE size)     /* [out] Address of struct receiving dimensions */
 726 {
 727     BITMAPOBJ * bmp = (BITMAPOBJ *) GDI_GetObjPtr( hbitmap, BITMAP_MAGIC );
 728     if (!bmp) return FALSE;
 729     *size = bmp->size;
 730     GDI_ReleaseObj( hbitmap );
 731     return TRUE;
 732 }
 733
 734
 735 /******************************************************************************
 736  * SetBitmapDimensionEx [GDI32.@]
 737  *
 738  * Assigns dimensions to a bitmap.
 739  * MSDN says that this function will fail if hbitmap is a handle created by
 740  * CreateDIBSection, but that's not true on Windows 2000.
 741  *
 742  * RETURNS
 743  *    Success: TRUE
 744  *    Failure: FALSE
 745  */
 746 BOOL WINAPI SetBitmapDimensionEx(
 747     HBITMAP hbitmap, /* [in]  Handle to bitmap */
 748     INT x,           /* [in]  Bitmap width */
 749     INT y,           /* [in]  Bitmap height */
 750     LPSIZE prevSize) /* [out] Address of structure for orig dims */
 751 {
 752     BITMAPOBJ * bmp = (BITMAPOBJ *) GDI_GetObjPtr( hbitmap, BITMAP_MAGIC );
 753     if (!bmp) return FALSE;
 754     if (prevSize) *prevSize = bmp->size;
 755     bmp->size.cx = x;
 756     bmp->size.cy = y;
 757     GDI_ReleaseObj( hbitmap );
 758     return TRUE;
 759 }