dlls/gdi32/painting.c

   1 /*
   2  * GDI drawing functions.
   3  *
   4  * Copyright 1993, 1994 Alexandre Julliard
   5  * Copyright 1997 Bertho A. Stultiens
   6  *           1999 Huw D M Davies
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  21  */
  22
  23 #include "config.h"
  24 #include "wine/port.h"
  25
  26 #include <stdarg.h>
  27 #include <string.h>
  28 #include <stdlib.h>
  29
  30 #include "windef.h"
  31 #include "winbase.h"
  32 #include "wingdi.h"
  33 #include "winerror.h"
  34 #include "gdi_private.h"
  35 #include "wine/debug.h"
  36
  37 WINE_DEFAULT_DEBUG_CHANNEL(gdi);
  38
  39
  40 /***********************************************************************
  41  *           LineTo    (GDI32.@)
  42  */
  43 BOOL WINAPI LineTo( HDC hdc, INT x, INT y )
  44 {
  45     DC * dc = DC_GetDCUpdate( hdc );
  46     BOOL ret;
  47
  48     if(!dc) return FALSE;
  49
  50     if(PATH_IsPathOpen(dc->path))
  51         ret = PATH_LineTo(dc, x, y);
  52     else
  53         ret = dc->funcs->pLineTo && dc->funcs->pLineTo(dc->physDev,x,y);
  54     if(ret) {
  55         dc->CursPosX = x;
  56         dc->CursPosY = y;
  57     }
  58     GDI_ReleaseObj( hdc );
  59     return ret;
  60 }
  61
  62
  63 /***********************************************************************
  64  *           MoveToEx    (GDI32.@)
  65  */
  66 BOOL WINAPI MoveToEx( HDC hdc, INT x, INT y, LPPOINT pt )
  67 {
  68     BOOL ret = TRUE;
  69     DC * dc = DC_GetDCPtr( hdc );
  70
  71     if(!dc) return FALSE;
  72
  73     if(pt) {
  74         pt->x = dc->CursPosX;
  75         pt->y = dc->CursPosY;
  76     }
  77     dc->CursPosX = x;
  78     dc->CursPosY = y;
  79
  80     if(PATH_IsPathOpen(dc->path)) ret = PATH_MoveTo(dc);
  81     else if (dc->funcs->pMoveTo) ret = dc->funcs->pMoveTo(dc->physDev,x,y);
  82     GDI_ReleaseObj( hdc );
  83     return ret;
  84 }
  85
  86
  87 /***********************************************************************
  88  *           Arc    (GDI32.@)
  89  */
  90 BOOL WINAPI Arc( HDC hdc, INT left, INT top, INT right,
  91                      INT bottom, INT xstart, INT ystart,
  92                      INT xend, INT yend )
  93 {
  94     BOOL ret = FALSE;
  95     DC * dc = DC_GetDCUpdate( hdc );
  96     if (dc)
  97     {
  98     if(PATH_IsPathOpen(dc->path))
  99             ret = PATH_Arc(dc, left, top, right, bottom, xstart, ystart, xend, yend,0);
 100         else if (dc->funcs->pArc)
 101             ret = dc->funcs->pArc(dc->physDev,left,top,right,bottom,xstart,ystart,xend,yend);
 102         GDI_ReleaseObj( hdc );
 103     }
 104     return ret;
 105 }
 106
 107 /***********************************************************************
 108  *           ArcTo    (GDI32.@)
 109  */
 110 BOOL WINAPI ArcTo( HDC hdc,
 111                      INT left,   INT top,
 112                      INT right,  INT bottom,
 113                      INT xstart, INT ystart,
 114                      INT xend,   INT yend )
 115 {
 116     BOOL result;
 117     DC * dc = DC_GetDCUpdate( hdc );
 118     if(!dc) return FALSE;
 119
 120     if(dc->funcs->pArcTo)
 121     {
 122         result = dc->funcs->pArcTo( dc->physDev, left, top, right, bottom,
 123                                   xstart, ystart, xend, yend );
 124         GDI_ReleaseObj( hdc );
 125         return result;
 126     }
 127     GDI_ReleaseObj( hdc );
 128     /*
 129      * Else emulate it.
 130      * According to the documentation, a line is drawn from the current
 131      * position to the starting point of the arc.
 132      */
 133     LineTo(hdc, xstart, ystart);
 134     /*
 135      * Then the arc is drawn.
 136      */
 137     result = Arc(hdc, left, top, right, bottom, xstart, ystart, xend, yend);
 138     /*
 139      * If no error occurred, the current position is moved to the ending
 140      * point of the arc.
 141      */
 142     if (result) MoveToEx(hdc, xend, yend, NULL);
 143     return result;
 144 }
 145
 146
 147 /***********************************************************************
 148  *           Pie   (GDI32.@)
 149  */
 150 BOOL WINAPI Pie( HDC hdc, INT left, INT top,
 151                      INT right, INT bottom, INT xstart, INT ystart,
 152                      INT xend, INT yend )
 153 {
 154     BOOL ret = FALSE;
 155     DC * dc = DC_GetDCUpdate( hdc );
 156     if (!dc) return FALSE;
 157
 158     if(PATH_IsPathOpen(dc->path))
 159         ret = PATH_Arc(dc,left,top,right,bottom,xstart,ystart,xend,yend,2);
 160     else if(dc->funcs->pPie)
 161         ret = dc->funcs->pPie(dc->physDev,left,top,right,bottom,xstart,ystart,xend,yend);
 162
 163     GDI_ReleaseObj( hdc );
 164     return ret;
 165 }
 166
 167
 168 /***********************************************************************
 169  *           Chord    (GDI32.@)
 170  */
 171 BOOL WINAPI Chord( HDC hdc, INT left, INT top,
 172                        INT right, INT bottom, INT xstart, INT ystart,
 173                        INT xend, INT yend )
 174 {
 175     BOOL ret = FALSE;
 176     DC * dc = DC_GetDCUpdate( hdc );
 177     if (!dc) return FALSE;
 178
 179     if(PATH_IsPathOpen(dc->path))
 180         ret = PATH_Arc(dc,left,top,right,bottom,xstart,ystart,xend,yend,1);
 181     else if(dc->funcs->pChord)
 182         ret = dc->funcs->pChord(dc->physDev,left,top,right,bottom,xstart,ystart,xend,yend);
 183
 184     GDI_ReleaseObj( hdc );
 185     return ret;
 186 }
 187
 188
 189 /***********************************************************************
 190  *           Ellipse    (GDI32.@)
 191  */
 192 BOOL WINAPI Ellipse( HDC hdc, INT left, INT top,
 193                          INT right, INT bottom )
 194 {
 195     BOOL ret = FALSE;
 196     DC * dc = DC_GetDCUpdate( hdc );
 197     if (!dc) return FALSE;
 198
 199     if(PATH_IsPathOpen(dc->path))
 200         ret = PATH_Ellipse(dc,left,top,right,bottom);
 201     else if (dc->funcs->pEllipse)
 202         ret = dc->funcs->pEllipse(dc->physDev,left,top,right,bottom);
 203
 204     GDI_ReleaseObj( hdc );
 205     return ret;
 206 }
 207
 208
 209 /***********************************************************************
 210  *           Rectangle    (GDI32.@)
 211  */
 212 BOOL WINAPI Rectangle( HDC hdc, INT left, INT top,
 213                            INT right, INT bottom )
 214 {
 215     BOOL ret = FALSE;
 216     DC * dc = DC_GetDCUpdate( hdc );
 217     if (dc)
 218     {
 219     if(PATH_IsPathOpen(dc->path))
 220             ret = PATH_Rectangle(dc, left, top, right, bottom);
 221         else if (dc->funcs->pRectangle)
 222             ret = dc->funcs->pRectangle(dc->physDev,left,top,right,bottom);
 223         GDI_ReleaseObj( hdc );
 224     }
 225     return ret;
 226 }
 227
 228
 229 /***********************************************************************
 230  *           RoundRect    (GDI32.@)
 231  */
 232 BOOL WINAPI RoundRect( HDC hdc, INT left, INT top, INT right,
 233                            INT bottom, INT ell_width, INT ell_height )
 234 {
 235     BOOL ret = FALSE;
 236     DC *dc = DC_GetDCUpdate( hdc );
 237
 238     if (dc)
 239     {
 240         if(PATH_IsPathOpen(dc->path))
 241             ret = PATH_RoundRect(dc,left,top,right,bottom,ell_width,ell_height);
 242         else if (dc->funcs->pRoundRect)
 243             ret = dc->funcs->pRoundRect(dc->physDev,left,top,right,bottom,ell_width,ell_height);
 244         GDI_ReleaseObj( hdc );
 245     }
 246     return ret;
 247 }
 248
 249 /***********************************************************************
 250  *           SetPixel    (GDI32.@)
 251  */
 252 COLORREF WINAPI SetPixel( HDC hdc, INT x, INT y, COLORREF color )
 253 {
 254     COLORREF ret = 0;
 255     DC * dc = DC_GetDCUpdate( hdc );
 256     if (dc)
 257     {
 258         if (dc->funcs->pSetPixel) ret = dc->funcs->pSetPixel(dc->physDev,x,y,color);
 259         GDI_ReleaseObj( hdc );
 260     }
 261     return ret;
 262 }
 263
 264 /***********************************************************************
 265  *           SetPixelV    (GDI32.@)
 266  */
 267 BOOL WINAPI SetPixelV( HDC hdc, INT x, INT y, COLORREF color )
 268 {
 269     BOOL ret = FALSE;
 270     DC * dc = DC_GetDCUpdate( hdc );
 271     if (dc)
 272     {
 273         if (dc->funcs->pSetPixel)
 274         {
 275             dc->funcs->pSetPixel(dc->physDev,x,y,color);
 276             ret = TRUE;
 277         }
 278         GDI_ReleaseObj( hdc );
 279     }
 280     return ret;
 281 }
 282
 283 /***********************************************************************
 284  *           GetPixel    (GDI32.@)
 285  */
 286 COLORREF WINAPI GetPixel( HDC hdc, INT x, INT y )
 287 {
 288     COLORREF ret = CLR_INVALID;
 289     DC * dc = DC_GetDCUpdate( hdc );
 290
 291     if (dc)
 292     {
 293     /* FIXME: should this be in the graphics driver? */
 294         if (PtVisible( hdc, x, y ))
 295         {
 296             if (dc->funcs->pGetPixel) ret = dc->funcs->pGetPixel(dc->physDev,x,y);
 297         }
 298         GDI_ReleaseObj( hdc );
 299     }
 300     return ret;
 301 }
 302
 303
 304 /******************************************************************************
 305  * ChoosePixelFormat [GDI32.@]
 306  * Matches a pixel format to given format
 307  *
 308  * PARAMS
 309  *    hdc  [I] Device context to search for best pixel match
 310  *    ppfd [I] Pixel format for which a match is sought
 311  *
 312  * RETURNS
 313  *    Success: Pixel format index closest to given format
 314  *    Failure: 0
 315  */
 316 INT WINAPI ChoosePixelFormat( HDC hdc, const PIXELFORMATDESCRIPTOR* ppfd )
 317 {
 318     INT ret = 0;
 319     DC * dc = DC_GetDCPtr( hdc );
 320
 321     TRACE("(%p,%p)\n",hdc,ppfd);
 322
 323     if (!dc) return 0;
 324
 325     if (!dc->funcs->pChoosePixelFormat) FIXME(" :stub\n");
 326     else ret = dc->funcs->pChoosePixelFormat(dc->physDev,ppfd);
 327
 328     GDI_ReleaseObj( hdc );
 329     return ret;
 330 }
 331
 332
 333 /******************************************************************************
 334  * SetPixelFormat [GDI32.@]
 335  * Sets pixel format of device context
 336  *
 337  * PARAMS
 338  *    hdc          [I] Device context to search for best pixel match
 339  *    iPixelFormat [I] Pixel format index
 340  *    ppfd         [I] Pixel format for which a match is sought
 341  *
 342  * RETURNS
 343  *    Success: TRUE
 344  *    Failure: FALSE
 345  */
 346 BOOL WINAPI SetPixelFormat( HDC hdc, INT iPixelFormat,
 347                             const PIXELFORMATDESCRIPTOR *ppfd)
 348 {
 349     INT bRet = FALSE;
 350     DC * dc = DC_GetDCPtr( hdc );
 351
 352     TRACE("(%p,%d,%p)\n",hdc,iPixelFormat,ppfd);
 353
 354     if (!dc) return 0;
 355
 356     if (!dc->funcs->pSetPixelFormat) FIXME(" :stub\n");
 357     else bRet = dc->funcs->pSetPixelFormat(dc->physDev,iPixelFormat,ppfd);
 358
 359     GDI_ReleaseObj( hdc );
 360     return bRet;
 361 }
 362
 363
 364 /******************************************************************************
 365  * GetPixelFormat [GDI32.@]
 366  * Gets index of pixel format of DC
 367  *
 368  * PARAMETERS
 369  *    hdc [I] Device context whose pixel format index is sought
 370  *
 371  * RETURNS
 372  *    Success: Currently selected pixel format
 373  *    Failure: 0
 374  */
 375 INT WINAPI GetPixelFormat( HDC hdc )
 376 {
 377     INT ret = 0;
 378     DC * dc = DC_GetDCPtr( hdc );
 379
 380     TRACE("(%p)\n",hdc);
 381
 382     if (!dc) return 0;
 383
 384     if (!dc->funcs->pGetPixelFormat) FIXME(" :stub\n");
 385     else ret = dc->funcs->pGetPixelFormat(dc->physDev);
 386
 387     GDI_ReleaseObj( hdc );
 388     return ret;
 389 }
 390
 391
 392 /******************************************************************************
 393  * DescribePixelFormat [GDI32.@]
 394  * Gets info about pixel format from DC
 395  *
 396  * PARAMS
 397  *    hdc          [I] Device context
 398  *    iPixelFormat [I] Pixel format selector
 399  *    nBytes       [I] Size of buffer
 400  *    ppfd         [O] Pointer to structure to receive pixel format data
 401  *
 402  * RETURNS
 403  *    Success: Maximum pixel format index of the device context
 404  *    Failure: 0
 405  */
 406 INT WINAPI DescribePixelFormat( HDC hdc, INT iPixelFormat, UINT nBytes,
 407                                 LPPIXELFORMATDESCRIPTOR ppfd )
 408 {
 409     INT ret = 0;
 410     DC * dc = DC_GetDCPtr( hdc );
 411
 412     TRACE("(%p,%d,%d,%p): stub\n",hdc,iPixelFormat,nBytes,ppfd);
 413
 414     if (!dc) return 0;
 415
 416     if (!dc->funcs->pDescribePixelFormat)
 417     {
 418         FIXME(" :stub\n");
 419         ppfd->nSize = nBytes;
 420         ppfd->nVersion = 1;
 421         ret = 3;
 422     }
 423     else ret = dc->funcs->pDescribePixelFormat(dc->physDev,iPixelFormat,nBytes,ppfd);
 424
 425     GDI_ReleaseObj( hdc );
 426     return ret;
 427 }
 428
 429
 430 /******************************************************************************
 431  * SwapBuffers [GDI32.@]
 432  * Exchanges front and back buffers of window
 433  *
 434  * PARAMS
 435  *    hdc [I] Device context whose buffers get swapped
 436  *
 437  * RETURNS
 438  *    Success: TRUE
 439  *    Failure: FALSE
 440  */
 441 BOOL WINAPI SwapBuffers( HDC hdc )
 442 {
 443     INT bRet = FALSE;
 444     DC * dc = DC_GetDCPtr( hdc );
 445
 446     TRACE("(%p)\n",hdc);
 447
 448     if (!dc) return TRUE;
 449
 450     if (!dc->funcs->pSwapBuffers)
 451     {
 452         FIXME(" :stub\n");
 453         bRet = TRUE;
 454     }
 455     else bRet = dc->funcs->pSwapBuffers(dc->physDev);
 456
 457     GDI_ReleaseObj( hdc );
 458     return bRet;
 459 }
 460
 461
 462 /***********************************************************************
 463  *           PaintRgn    (GDI32.@)
 464  */
 465 BOOL WINAPI PaintRgn( HDC hdc, HRGN hrgn )
 466 {
 467     BOOL ret = FALSE;
 468     DC * dc = DC_GetDCUpdate( hdc );
 469     if (dc)
 470     {
 471         if (dc->funcs->pPaintRgn) ret = dc->funcs->pPaintRgn(dc->physDev,hrgn);
 472         GDI_ReleaseObj( hdc );
 473     }
 474     return ret;
 475 }
 476
 477
 478 /***********************************************************************
 479  *           FillRgn    (GDI32.@)
 480  */
 481 BOOL WINAPI FillRgn( HDC hdc, HRGN hrgn, HBRUSH hbrush )
 482 {
 483     BOOL retval = FALSE;
 484     HBRUSH prevBrush;
 485     DC * dc = DC_GetDCUpdate( hdc );
 486
 487     if (!dc) return FALSE;
 488     if(dc->funcs->pFillRgn)
 489         retval = dc->funcs->pFillRgn(dc->physDev, hrgn, hbrush);
 490     else if ((prevBrush = SelectObject( hdc, hbrush )))
 491     {
 492     retval = PaintRgn( hdc, hrgn );
 493     SelectObject( hdc, prevBrush );
 494     }
 495     GDI_ReleaseObj( hdc );
 496     return retval;
 497 }
 498
 499
 500 /***********************************************************************
 501  *           FrameRgn     (GDI32.@)
 502  */
 503 BOOL WINAPI FrameRgn( HDC hdc, HRGN hrgn, HBRUSH hbrush,
 504                           INT nWidth, INT nHeight )
 505 {
 506     BOOL ret = FALSE;
 507     DC *dc = DC_GetDCUpdate( hdc );
 508
 509     if (!dc) return FALSE;
 510     if(dc->funcs->pFrameRgn)
 511         ret = dc->funcs->pFrameRgn( dc->physDev, hrgn, hbrush, nWidth, nHeight );
 512     else
 513     {
 514         HRGN tmp = CreateRectRgn( 0, 0, 0, 0 );
 515         if (tmp)
 516         {
 517             if (REGION_FrameRgn( tmp, hrgn, nWidth, nHeight ))
 518             {
 519                 FillRgn( hdc, tmp, hbrush );
 520                 ret = TRUE;
 521             }
 522             DeleteObject( tmp );
 523         }
 524     }
 525     GDI_ReleaseObj( hdc );
 526     return ret;
 527 }
 528
 529
 530 /***********************************************************************
 531  *           InvertRgn    (GDI32.@)
 532  */
 533 BOOL WINAPI InvertRgn( HDC hdc, HRGN hrgn )
 534 {
 535     HBRUSH prevBrush;
 536     INT prevROP;
 537     BOOL retval;
 538     DC *dc = DC_GetDCUpdate( hdc );
 539     if (!dc) return FALSE;
 540
 541     if(dc->funcs->pInvertRgn)
 542         retval = dc->funcs->pInvertRgn( dc->physDev, hrgn );
 543     else
 544     {
 545     prevBrush = SelectObject( hdc, GetStockObject(BLACK_BRUSH) );
 546     prevROP = SetROP2( hdc, R2_NOT );
 547     retval = PaintRgn( hdc, hrgn );
 548     SelectObject( hdc, prevBrush );
 549     SetROP2( hdc, prevROP );
 550     }
 551     GDI_ReleaseObj( hdc );
 552     return retval;
 553 }
 554
 555
 556 /**********************************************************************
 557  *          Polyline   (GDI32.@)
 558  */
 559 BOOL WINAPI Polyline( HDC hdc, const POINT* pt, INT count )
 560 {
 561     BOOL ret = FALSE;
 562     DC * dc = DC_GetDCUpdate( hdc );
 563     if (dc)
 564     {
 565         if (PATH_IsPathOpen(dc->path)) ret = PATH_Polyline(dc, pt, count);
 566         else if (dc->funcs->pPolyline) ret = dc->funcs->pPolyline(dc->physDev,pt,count);
 567         GDI_ReleaseObj( hdc );
 568     }
 569     return ret;
 570 }
 571
 572 /**********************************************************************
 573  *          PolylineTo   (GDI32.@)
 574  */
 575 BOOL WINAPI PolylineTo( HDC hdc, const POINT* pt, DWORD cCount )
 576 {
 577     DC * dc = DC_GetDCUpdate( hdc );
 578     BOOL ret = FALSE;
 579
 580     if(!dc) return FALSE;
 581
 582     if(PATH_IsPathOpen(dc->path))
 583         ret = PATH_PolylineTo(dc, pt, cCount);
 584
 585     else if(dc->funcs->pPolylineTo)
 586         ret = dc->funcs->pPolylineTo(dc->physDev, pt, cCount);
 587
 588     else { /* do it using Polyline */
 589         POINT *pts = HeapAlloc( GetProcessHeap(), 0,
 590                                 sizeof(POINT) * (cCount + 1) );
 591         if (pts)
 592         {
 593         pts[0].x = dc->CursPosX;
 594         pts[0].y = dc->CursPosY;
 595         memcpy( pts + 1, pt, sizeof(POINT) * cCount );
 596         ret = Polyline( hdc, pts, cCount + 1 );
 597         HeapFree( GetProcessHeap(), 0, pts );
 598     }
 599     }
 600     if(ret) {
 601         dc->CursPosX = pt[cCount-1].x;
 602         dc->CursPosY = pt[cCount-1].y;
 603     }
 604     GDI_ReleaseObj( hdc );
 605     return ret;
 606 }
 607
 608
 609 /**********************************************************************
 610  *          Polygon  (GDI32.@)
 611  */
 612 BOOL WINAPI Polygon( HDC hdc, const POINT* pt, INT count )
 613 {
 614     BOOL ret = FALSE;
 615     DC * dc = DC_GetDCUpdate( hdc );
 616     if (dc)
 617     {
 618         if (PATH_IsPathOpen(dc->path)) ret = PATH_Polygon(dc, pt, count);
 619         else if (dc->funcs->pPolygon) ret = dc->funcs->pPolygon(dc->physDev,pt,count);
 620         GDI_ReleaseObj( hdc );
 621     }
 622     return ret;
 623 }
 624
 625
 626 /**********************************************************************
 627  *          PolyPolygon  (GDI32.@)
 628  */
 629 BOOL WINAPI PolyPolygon( HDC hdc, const POINT* pt, const INT* counts,
 630                              UINT polygons )
 631 {
 632     BOOL ret = FALSE;
 633     DC * dc = DC_GetDCUpdate( hdc );
 634     if (dc)
 635     {
 636         if (PATH_IsPathOpen(dc->path)) ret = PATH_PolyPolygon(dc, pt, counts, polygons);
 637         else if (dc->funcs->pPolyPolygon) ret = dc->funcs->pPolyPolygon(dc->physDev,pt,counts,polygons);
 638         GDI_ReleaseObj( hdc );
 639     }
 640     return ret;
 641 }
 642
 643 /**********************************************************************
 644  *          PolyPolyline  (GDI32.@)
 645  */
 646 BOOL WINAPI PolyPolyline( HDC hdc, const POINT* pt, const DWORD* counts,
 647                             DWORD polylines )
 648 {
 649     BOOL ret = FALSE;
 650     DC * dc = DC_GetDCUpdate( hdc );
 651     if (dc)
 652     {
 653         if (PATH_IsPathOpen(dc->path)) ret = PATH_PolyPolyline(dc, pt, counts, polylines);
 654         else if (dc->funcs->pPolyPolyline) ret = dc->funcs->pPolyPolyline(dc->physDev,pt,counts,polylines);
 655         GDI_ReleaseObj( hdc );
 656     }
 657     return ret;
 658 }
 659
 660 /**********************************************************************
 661  *          ExtFloodFill   (GDI32.@)
 662  */
 663 BOOL WINAPI ExtFloodFill( HDC hdc, INT x, INT y, COLORREF color,
 664                               UINT fillType )
 665 {
 666     BOOL ret = FALSE;
 667     DC * dc = DC_GetDCUpdate( hdc );
 668     if (dc)
 669     {
 670         if (dc->funcs->pExtFloodFill) ret = dc->funcs->pExtFloodFill(dc->physDev,x,y,color,fillType);
 671         GDI_ReleaseObj( hdc );
 672     }
 673     return ret;
 674 }
 675
 676
 677 /**********************************************************************
 678  *          FloodFill   (GDI32.@)
 679  */
 680 BOOL WINAPI FloodFill( HDC hdc, INT x, INT y, COLORREF color )
 681 {
 682     return ExtFloodFill( hdc, x, y, color, FLOODFILLBORDER );
 683 }
 684
 685
 686 /******************************************************************************
 687  * PolyBezier [GDI32.@]
 688  * Draws one or more Bezier curves
 689  *
 690  * PARAMS
 691  *    hDc     [I] Handle to device context
 692  *    lppt    [I] Pointer to endpoints and control points
 693  *    cPoints [I] Count of endpoints and control points
 694  *
 695  * RETURNS
 696  *    Success: TRUE
 697  *    Failure: FALSE
 698  */
 699 BOOL WINAPI PolyBezier( HDC hdc, const POINT* lppt, DWORD cPoints )
 700 {
 701     BOOL ret = FALSE;
 702     DC * dc;
 703
 704     /* cPoints must be 3 * n + 1 (where n>=1) */
 705     if (cPoints == 1 || (cPoints % 3) != 1) return FALSE;
 706
 707     dc = DC_GetDCUpdate( hdc );
 708     if(!dc) return FALSE;
 709
 710     if(PATH_IsPathOpen(dc->path))
 711         ret = PATH_PolyBezier(dc, lppt, cPoints);
 712     else if (dc->funcs->pPolyBezier)
 713         ret = dc->funcs->pPolyBezier(dc->physDev, lppt, cPoints);
 714     else  /* We'll convert it into line segments and draw them using Polyline */
 715     {
 716         POINT *Pts;
 717         INT nOut;
 718
 719         if ((Pts = GDI_Bezier( lppt, cPoints, &nOut )))
 720         {
 721             TRACE("Pts = %p, no = %d\n", Pts, nOut);
 722             ret = Polyline( dc->hSelf, Pts, nOut );
 723             HeapFree( GetProcessHeap(), 0, Pts );
 724         }
 725     }
 726
 727     GDI_ReleaseObj( hdc );
 728     return ret;
 729 }
 730
 731 /******************************************************************************
 732  * PolyBezierTo [GDI32.@]
 733  * Draws one or more Bezier curves
 734  *
 735  * PARAMS
 736  *    hDc     [I] Handle to device context
 737  *    lppt    [I] Pointer to endpoints and control points
 738  *    cPoints [I] Count of endpoints and control points
 739  *
 740  * RETURNS
 741  *    Success: TRUE
 742  *    Failure: FALSE
 743  */
 744 BOOL WINAPI PolyBezierTo( HDC hdc, const POINT* lppt, DWORD cPoints )
 745 {
 746     DC * dc;
 747     BOOL ret;
 748
 749     /* cbPoints must be 3 * n (where n>=1) */
 750     if (!cPoints || (cPoints % 3) != 0) return FALSE;
 751
 752     dc = DC_GetDCUpdate( hdc );
 753     if(!dc) return FALSE;
 754
 755     if(PATH_IsPathOpen(dc->path))
 756         ret = PATH_PolyBezierTo(dc, lppt, cPoints);
 757     else if(dc->funcs->pPolyBezierTo)
 758         ret = dc->funcs->pPolyBezierTo(dc->physDev, lppt, cPoints);
 759     else { /* We'll do it using PolyBezier */
 760         POINT *pt;
 761         pt = HeapAlloc( GetProcessHeap(), 0, sizeof(POINT) * (cPoints + 1) );
 762         if(!pt) return FALSE;
 763         pt[0].x = dc->CursPosX;
 764         pt[0].y = dc->CursPosY;
 765         memcpy(pt + 1, lppt, sizeof(POINT) * cPoints);
 766         ret = PolyBezier(dc->hSelf, pt, cPoints+1);
 767         HeapFree( GetProcessHeap(), 0, pt );
 768     }
 769     if(ret) {
 770         dc->CursPosX = lppt[cPoints-1].x;
 771         dc->CursPosY = lppt[cPoints-1].y;
 772     }
 773     GDI_ReleaseObj( hdc );
 774     return ret;
 775 }
 776
 777 /***********************************************************************
 778  *      AngleArc (GDI32.@)
 779  */
 780 BOOL WINAPI AngleArc(HDC hdc, INT x, INT y, DWORD dwRadius, FLOAT eStartAngle, FLOAT eSweepAngle)
 781 {
 782     INT x1,y1,x2,y2, arcdir;
 783     BOOL result;
 784     DC *dc;
 785
 786     if( (signed int)dwRadius < 0 )
 787         return FALSE;
 788
 789     dc = DC_GetDCUpdate( hdc );
 790     if(!dc) return FALSE;
 791
 792     if(dc->funcs->pAngleArc)
 793     {
 794         result = dc->funcs->pAngleArc( dc->physDev, x, y, dwRadius, eStartAngle, eSweepAngle );
 795
 796         GDI_ReleaseObj( hdc );
 797         return result;
 798     }
 799     GDI_ReleaseObj( hdc );
 800
 801     /* AngleArc always works counterclockwise */
 802     arcdir = GetArcDirection( hdc );
 803     SetArcDirection( hdc, AD_COUNTERCLOCKWISE );
 804
 805     x1 = x + cos(eStartAngle*M_PI/180) * dwRadius;
 806     y1 = y - sin(eStartAngle*M_PI/180) * dwRadius;
 807     x2 = x + cos((eStartAngle+eSweepAngle)*M_PI/180) * dwRadius;
 808     y2 = y - sin((eStartAngle+eSweepAngle)*M_PI/180) * dwRadius;
 809
 810     LineTo( hdc, x1, y1 );
 811     if( eSweepAngle >= 0 )
 812         result = Arc( hdc, x-dwRadius, y-dwRadius, x+dwRadius, y+dwRadius,
 813                       x1, y1, x2, y2 );
 814     else
 815         result = Arc( hdc, x-dwRadius, y-dwRadius, x+dwRadius, y+dwRadius,
 816                       x2, y2, x1, y1 );
 817
 818     if( result ) MoveToEx( hdc, x2, y2, NULL );
 819     SetArcDirection( hdc, arcdir );
 820     return result;
 821 }
 822
 823 /***********************************************************************
 824  *      PolyDraw (GDI32.@)
 825  */
 826 BOOL WINAPI PolyDraw(HDC hdc, const POINT *lppt, const BYTE *lpbTypes,
 827                        DWORD cCount)
 828 {
 829     DC *dc;
 830     BOOL result;
 831     POINT lastmove;
 832     unsigned int i;
 833
 834     dc = DC_GetDCUpdate( hdc );
 835     if(!dc) return FALSE;
 836
 837     if(dc->funcs->pPolyDraw)
 838     {
 839         result = dc->funcs->pPolyDraw( dc->physDev, lppt, lpbTypes, cCount );
 840         GDI_ReleaseObj( hdc );
 841         return result;
 842     }
 843     GDI_ReleaseObj( hdc );
 844
 845     /* check for each bezierto if there are two more points */
 846     for( i = 0; i < cCount; i++ )
 847         if( lpbTypes[i] != PT_MOVETO &&
 848             lpbTypes[i] & PT_BEZIERTO )
 849         {
 850             if( cCount < i+3 )
 851                 return FALSE;
 852             else
 853                 i += 2;
 854         }
 855
 856     /* if no moveto occurs, we will close the figure here */
 857     lastmove.x = dc->CursPosX;
 858     lastmove.y = dc->CursPosY;
 859
 860     /* now let's draw */
 861     for( i = 0; i < cCount; i++ )
 862     {
 863         if( lpbTypes[i] == PT_MOVETO )
 864         {
 865             MoveToEx( hdc, lppt[i].x, lppt[i].y, NULL );
 866             lastmove.x = dc->CursPosX;
 867             lastmove.y = dc->CursPosY;
 868         }
 869         else if( lpbTypes[i] & PT_LINETO )
 870             LineTo( hdc, lppt[i].x, lppt[i].y );
 871         else if( lpbTypes[i] & PT_BEZIERTO )
 872         {
 873             PolyBezierTo( hdc, &lppt[i], 3 );
 874             i += 2;
 875         }
 876         else
 877             return FALSE;
 878
 879         if( lpbTypes[i] & PT_CLOSEFIGURE )
 880         {
 881             if( PATH_IsPathOpen( dc->path ) )
 882                 CloseFigure( hdc );
 883             else
 884                 LineTo( hdc, lastmove.x, lastmove.y );
 885         }
 886     }
 887
 888     return TRUE;
 889 }
 890
 891
 892 /**********************************************************************
 893  *           LineDDA   (GDI32.@)
 894  */
 895 BOOL WINAPI LineDDA(INT nXStart, INT nYStart, INT nXEnd, INT nYEnd,
 896                     LINEDDAPROC callback, LPARAM lParam )
 897 {
 898     INT xadd = 1, yadd = 1;
 899     INT err,erradd;
 900     INT cnt;
 901     INT dx = nXEnd - nXStart;
 902     INT dy = nYEnd - nYStart;
 903
 904     if (dx < 0)
 905     {
 906         dx = -dx;
 907         xadd = -1;
 908     }
 909     if (dy < 0)
 910     {
 911         dy = -dy;
 912         yadd = -1;
 913     }
 914     if (dx > dy)  /* line is "more horizontal" */
 915     {
 916         err = 2*dy - dx; erradd = 2*dy - 2*dx;
 917         for(cnt = 0;cnt <= dx; cnt++)
 918         {
 919             callback(nXStart,nYStart,lParam);
 920             if (err > 0)
 921             {
 922                 nYStart += yadd;
 923                 err += erradd;
 924             }
 925             else err += 2*dy;
 926             nXStart += xadd;
 927         }
 928     }
 929     else   /* line is "more vertical" */
 930     {
 931         err = 2*dx - dy; erradd = 2*dx - 2*dy;
 932         for(cnt = 0;cnt <= dy; cnt++)
 933         {
 934             callback(nXStart,nYStart,lParam);
 935             if (err > 0)
 936             {
 937                 nXStart += xadd;
 938                 err += erradd;
 939             }
 940             else err += 2*dx;
 941             nYStart += yadd;
 942         }
 943     }
 944     return TRUE;
 945 }
 946
 947
 948 /******************************************************************
 949  *
 950  *   *Very* simple bezier drawing code,
 951  *
 952  *   It uses a recursive algorithm to divide the curve in a series
 953  *   of straight line segements. Not ideal but for me sufficient.
 954  *   If you are in need for something better look for some incremental
 955  *   algorithm.
 956  *
 957  *   7 July 1998 Rein Klazes
 958  */
 959
 960  /*
 961   * some macro definitions for bezier drawing
 962   *
 963   * to avoid truncation errors the coordinates are
 964   * shifted upwards. When used in drawing they are
 965   * shifted down again, including correct rounding
 966   * and avoiding floating point arithmetic
 967   * 4 bits should allow 27 bits coordinates which I saw
 968   * somewhere in the win32 doc's
 969   *
 970   */
 971
 972 #define BEZIERSHIFTBITS 4
 973 #define BEZIERSHIFTUP(x)    ((x)<<BEZIERSHIFTBITS)
 974 #define BEZIERPIXEL        BEZIERSHIFTUP(1)
 975 #define BEZIERSHIFTDOWN(x)  (((x)+(1<<(BEZIERSHIFTBITS-1)))>>BEZIERSHIFTBITS)
 976 /* maximum depth of recursion */
 977 #define BEZIERMAXDEPTH  8
 978
 979 /* size of array to store points on */
 980 /* enough for one curve */
 981 #define BEZIER_INITBUFSIZE    (150)
 982
 983 /* calculate Bezier average, in this case the middle
 984  * correctly rounded...
 985  * */
 986
 987 #define BEZIERMIDDLE(Mid, P1, P2) \
 988     (Mid).x=((P1).x+(P2).x + 1)/2;\
 989     (Mid).y=((P1).y+(P2).y + 1)/2;
 990
 991 /**********************************************************
 992 * BezierCheck helper function to check
 993 * that recursion can be terminated
 994 *       Points[0] and Points[3] are begin and endpoint
 995 *       Points[1] and Points[2] are control points
 996 *       level is the recursion depth
 997 *       returns true if the recusion can be terminated
 998 */
 999 static BOOL BezierCheck( int level, POINT *Points)
1000 {
1001     INT dx, dy;
1002     dx=Points[3].x-Points[0].x;
1003     dy=Points[3].y-Points[0].y;
1004     if(abs(dy)<=abs(dx)){/* shallow line */
1005         /* check that control points are between begin and end */
1006         if(Points[1].x < Points[0].x){
1007             if(Points[1].x < Points[3].x)
1008                 return FALSE;
1009         }else
1010             if(Points[1].x > Points[3].x)
1011                 return FALSE;
1012         if(Points[2].x < Points[0].x){
1013             if(Points[2].x < Points[3].x)
1014                 return FALSE;
1015         }else
1016             if(Points[2].x > Points[3].x)
1017                 return FALSE;
1018         dx=BEZIERSHIFTDOWN(dx);
1019         if(!dx) return TRUE;
1020         if(abs(Points[1].y-Points[0].y-(dy/dx)*
1021                 BEZIERSHIFTDOWN(Points[1].x-Points[0].x)) > BEZIERPIXEL ||
1022            abs(Points[2].y-Points[0].y-(dy/dx)*
1023                    BEZIERSHIFTDOWN(Points[2].x-Points[0].x)) > BEZIERPIXEL )
1024             return FALSE;
1025         else
1026             return TRUE;
1027     }else{ /* steep line */
1028         /* check that control points are between begin and end */
1029         if(Points[1].y < Points[0].y){
1030             if(Points[1].y < Points[3].y)
1031                 return FALSE;
1032         }else
1033             if(Points[1].y > Points[3].y)
1034                 return FALSE;
1035         if(Points[2].y < Points[0].y){
1036             if(Points[2].y < Points[3].y)
1037                 return FALSE;
1038         }else
1039             if(Points[2].y > Points[3].y)
1040                 return FALSE;
1041         dy=BEZIERSHIFTDOWN(dy);
1042         if(!dy) return TRUE;
1043         if(abs(Points[1].x-Points[0].x-(dx/dy)*
1044                 BEZIERSHIFTDOWN(Points[1].y-Points[0].y)) > BEZIERPIXEL ||
1045            abs(Points[2].x-Points[0].x-(dx/dy)*
1046                    BEZIERSHIFTDOWN(Points[2].y-Points[0].y)) > BEZIERPIXEL )
1047             return FALSE;
1048         else
1049             return TRUE;
1050     }
1051 }
1052
1053 /* Helper for GDI_Bezier.
1054  * Just handles one Bezier, so Points should point to four POINTs
1055  */
1056 static void GDI_InternalBezier( POINT *Points, POINT **PtsOut, INT *dwOut,
1057                                 INT *nPtsOut, INT level )
1058 {
1059     if(*nPtsOut == *dwOut) {
1060         *dwOut *= 2;
1061         *PtsOut = HeapReAlloc( GetProcessHeap(), 0, *PtsOut,
1062                                *dwOut * sizeof(POINT) );
1063     }
1064
1065     if(!level || BezierCheck(level, Points)) {
1066         if(*nPtsOut == 0) {
1067             (*PtsOut)[0].x = BEZIERSHIFTDOWN(Points[0].x);
1068             (*PtsOut)[0].y = BEZIERSHIFTDOWN(Points[0].y);
1069             *nPtsOut = 1;
1070         }
1071         (*PtsOut)[*nPtsOut].x = BEZIERSHIFTDOWN(Points[3].x);
1072         (*PtsOut)[*nPtsOut].y = BEZIERSHIFTDOWN(Points[3].y);
1073         (*nPtsOut) ++;
1074     } else {
1075         POINT Points2[4]; /* for the second recursive call */
1076         Points2[3]=Points[3];
1077         BEZIERMIDDLE(Points2[2], Points[2], Points[3]);
1078         BEZIERMIDDLE(Points2[0], Points[1], Points[2]);
1079         BEZIERMIDDLE(Points2[1],Points2[0],Points2[2]);
1080
1081         BEZIERMIDDLE(Points[1], Points[0],  Points[1]);
1082         BEZIERMIDDLE(Points[2], Points[1], Points2[0]);
1083         BEZIERMIDDLE(Points[3], Points[2], Points2[1]);
1084
1085         Points2[0]=Points[3];
1086
1087         /* do the two halves */
1088         GDI_InternalBezier(Points, PtsOut, dwOut, nPtsOut, level-1);
1089         GDI_InternalBezier(Points2, PtsOut, dwOut, nPtsOut, level-1);
1090     }
1091 }
1092
1093
1094
1095 /***********************************************************************
1096  *           GDI_Bezier   [INTERNAL]
1097  *   Calculate line segments that approximate -what microsoft calls- a bezier
1098  *   curve.
1099  *   The routine recursively divides the curve in two parts until a straight
1100  *   line can be drawn
1101  *
1102  *  PARAMS
1103  *
1104  *  Points  [I] Ptr to count POINTs which are the end and control points
1105  *              of the set of Bezier curves to flatten.
1106  *  count   [I] Number of Points.  Must be 3n+1.
1107  *  nPtsOut [O] Will contain no of points that have been produced (i.e. no. of
1108  *              lines+1).
1109  *
1110  *  RETURNS
1111  *
1112  *  Ptr to an array of POINTs that contain the lines that approximinate the
1113  *  Beziers.  The array is allocated on the process heap and it is the caller's
1114  *  responsibility to HeapFree it. [this is not a particularly nice interface
1115  *  but since we can't know in advance how many points will generate, the
1116  *  alternative would be to call the function twice, once to determine the size
1117  *  and a second time to do the work - I decided this was too much of a pain].
1118  */
1119 POINT *GDI_Bezier( const POINT *Points, INT count, INT *nPtsOut )
1120 {
1121     POINT *out;
1122     INT Bezier, dwOut = BEZIER_INITBUFSIZE, i;
1123
1124     if (count == 1 || (count - 1) % 3 != 0) {
1125         ERR("Invalid no. of points %d\n", count);
1126         return NULL;
1127     }
1128     *nPtsOut = 0;
1129     out = HeapAlloc( GetProcessHeap(), 0, dwOut * sizeof(POINT));
1130     for(Bezier = 0; Bezier < (count-1)/3; Bezier++) {
1131         POINT ptBuf[4];
1132         memcpy(ptBuf, Points + Bezier * 3, sizeof(POINT) * 4);
1133         for(i = 0; i < 4; i++) {
1134             ptBuf[i].x = BEZIERSHIFTUP(ptBuf[i].x);
1135             ptBuf[i].y = BEZIERSHIFTUP(ptBuf[i].y);
1136         }
1137         GDI_InternalBezier( ptBuf, &out, &dwOut, nPtsOut, BEZIERMAXDEPTH );
1138     }
1139     TRACE("Produced %d points\n", *nPtsOut);
1140     return out;
1141 }
1142
1143 /******************************************************************************
1144  *           GdiGradientFill   (GDI32.@)
1145  *
1146  *  FIXME: we don't support the Alpha channel properly
1147  */
1148 BOOL WINAPI GdiGradientFill( HDC hdc, TRIVERTEX *vert_array, ULONG nvert,
1149                           void * grad_array, ULONG ngrad, ULONG mode )
1150 {
1151   unsigned int i;
1152
1153   TRACE("vert_array:0x%08lx nvert:%d grad_array:0x%08lx ngrad:%d\n",
1154         (long)vert_array, nvert, (long)grad_array, ngrad);
1155
1156   switch(mode)
1157     {
1158     case GRADIENT_FILL_RECT_H:
1159       for(i = 0; i < ngrad; i++)
1160         {
1161           GRADIENT_RECT *rect = ((GRADIENT_RECT *)grad_array) + i;
1162           TRIVERTEX *v1 = vert_array + rect->UpperLeft;
1163           TRIVERTEX *v2 = vert_array + rect->LowerRight;
1164           int y1 = v1->y < v2->y ? v1->y : v2->y;
1165           int y2 = v2->y > v1->y ? v2->y : v1->y;
1166           int x, dx;
1167           if (v1->x > v2->x)
1168             {
1169               TRIVERTEX *t = v2;
1170               v2 = v1;
1171               v1 = t;
1172             }
1173           dx = v2->x - v1->x;
1174           for (x = 0; x < dx; x++)
1175             {
1176               POINT pts[2];
1177               HPEN hPen, hOldPen;
1178
1179               hPen = CreatePen( PS_SOLID, 1, RGB(
1180                   (v1->Red   * (dx - x) + v2->Red   * x) / dx >> 8,
1181                   (v1->Green * (dx - x) + v2->Green * x) / dx >> 8,
1182                   (v1->Blue  * (dx - x) + v2->Blue  * x) / dx >> 8));
1183               hOldPen = SelectObject( hdc, hPen );
1184               pts[0].x = v1->x + x;
1185               pts[0].y = y1;
1186               pts[1].x = v1->x + x;
1187               pts[1].y = y2;
1188               Polyline( hdc, &pts[0], 2 );
1189               DeleteObject( SelectObject(hdc, hOldPen ) );
1190             }
1191         }
1192       break;
1193     case GRADIENT_FILL_RECT_V:
1194       for(i = 0; i < ngrad; i++)
1195         {
1196           GRADIENT_RECT *rect = ((GRADIENT_RECT *)grad_array) + i;
1197           TRIVERTEX *v1 = vert_array + rect->UpperLeft;
1198           TRIVERTEX *v2 = vert_array + rect->LowerRight;
1199           int x1 = v1->x < v2->x ? v1->x : v2->x;
1200           int x2 = v2->x > v1->x ? v2->x : v1->x;
1201           int y, dy;
1202           if (v1->y > v2->y)
1203             {
1204               TRIVERTEX *t = v2;
1205               v2 = v1;
1206               v1 = t;
1207             }
1208           dy = v2->y - v1->y;
1209           for (y = 0; y < dy; y++)
1210             {
1211               POINT pts[2];
1212               HPEN hPen, hOldPen;
1213
1214               hPen = CreatePen( PS_SOLID, 1, RGB(
1215                   (v1->Red   * (dy - y) + v2->Red   * y) / dy >> 8,
1216                   (v1->Green * (dy - y) + v2->Green * y) / dy >> 8,
1217                   (v1->Blue  * (dy - y) + v2->Blue  * y) / dy >> 8));
1218               hOldPen = SelectObject( hdc, hPen );
1219               pts[0].x = x1;
1220               pts[0].y = v1->y + y;
1221               pts[1].x = x2;
1222               pts[1].y = v1->y + y;
1223               Polyline( hdc, &pts[0], 2 );
1224               DeleteObject( SelectObject(hdc, hOldPen ) );
1225             }
1226         }
1227       break;
1228     case GRADIENT_FILL_TRIANGLE:
1229       for (i = 0; i < ngrad; i++)
1230         {
1231           GRADIENT_TRIANGLE *tri = ((GRADIENT_TRIANGLE *)grad_array) + i;
1232           TRIVERTEX *v1 = vert_array + tri->Vertex1;
1233           TRIVERTEX *v2 = vert_array + tri->Vertex2;
1234           TRIVERTEX *v3 = vert_array + tri->Vertex3;
1235           int y, dy;
1236
1237           if (v1->y > v2->y)
1238             { TRIVERTEX *t = v1; v1 = v2; v2 = t; }
1239           if (v2->y > v3->y)
1240             {
1241               TRIVERTEX *t = v2; v2 = v3; v3 = t;
1242               if (v1->y > v2->y)
1243                 { t = v1; v1 = v2; v2 = t; }
1244             }
1245           /* v1->y <= v2->y <= v3->y */
1246
1247           dy = v3->y - v1->y;
1248           for (y = 0; y < dy; y++)
1249             {
1250               /* v1->y <= y < v3->y */
1251               TRIVERTEX *v = y < (v2->y - v1->y) ? v1 : v3;
1252               /* (v->y <= y < v2->y) || (v2->y <= y < v->y) */
1253               int dy2 = v2->y - v->y;
1254               int y2 = y + v1->y - v->y;
1255
1256               int x1 = (v3->x     * y  + v1->x     * (dy  - y )) / dy;
1257               int x2 = (v2->x     * y2 + v-> x     * (dy2 - y2)) / dy2;
1258               int r1 = (v3->Red   * y  + v1->Red   * (dy  - y )) / dy;
1259               int r2 = (v2->Red   * y2 + v-> Red   * (dy2 - y2)) / dy2;
1260               int g1 = (v3->Green * y  + v1->Green * (dy  - y )) / dy;
1261               int g2 = (v2->Green * y2 + v-> Green * (dy2 - y2)) / dy2;
1262               int b1 = (v3->Blue  * y  + v1->Blue  * (dy  - y )) / dy;
1263               int b2 = (v2->Blue  * y2 + v-> Blue  * (dy2 - y2)) / dy2;
1264
1265               int x;
1266               if (x1 < x2)
1267                 {
1268                   int dx = x2 - x1;
1269                   for (x = 0; x < dx; x++)
1270                     SetPixel (hdc, x + x1, y + v1->y, RGB(
1271                       (r1 * (dx - x) + r2 * x) / dx >> 8,
1272                       (g1 * (dx - x) + g2 * x) / dx >> 8,
1273                       (b1 * (dx - x) + b2 * x) / dx >> 8));
1274                 }
1275               else
1276                 {
1277                   int dx = x1 - x2;
1278                   for (x = 0; x < dx; x++)
1279                     SetPixel (hdc, x + x2, y + v1->y, RGB(
1280                       (r2 * (dx - x) + r1 * x) / dx >> 8,
1281                       (g2 * (dx - x) + g1 * x) / dx >> 8,
1282                       (b2 * (dx - x) + b1 * x) / dx >> 8));
1283                 }
1284             }
1285         }
1286       break;
1287     default:
1288       return FALSE;
1289   }
1290
1291   return TRUE;
1292 }