basegfx/source/polygon/b2dsvgpolypolygon.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <basegfx/polygon/b2dpolygontools.hxx>
  21 #include <basegfx/polygon/b2dpolypolygontools.hxx>
  22 #include <basegfx/polygon/b2dpolypolygon.hxx>
  23 #include <basegfx/matrix/b2dhommatrix.hxx>
  24 #include <basegfx/matrix/b2dhommatrixtools.hxx>
  25
  26 #include <rtl/ustring.hxx>
  27 #include <rtl/math.hxx>
  28 #include <stringconversiontools.hxx>
  29
  30 namespace basegfx
  31 {
  32     namespace utils
  33     {
  34         bool PointIndex::operator<(const PointIndex& rComp) const
  35         {
  36             if(rComp.getPolygonIndex() == getPolygonIndex())
  37             {
  38                 return rComp.getPointIndex() < getPointIndex();
  39             }
  40
  41             return rComp.getPolygonIndex() < getPolygonIndex();
  42         }
  43
  44         bool importFromSvgD(
  45             B2DPolyPolygon& o_rPolyPolygon,
  46             const OUString& rSvgDStatement,
  47             bool bHandleRelativeNextPointCompatible,
  48             PointIndexSet* pHelpPointIndexSet)
  49         {
  50             o_rPolyPolygon.clear();
  51             const sal_Int32 nLen(rSvgDStatement.getLength());
  52             sal_Int32 nPos(0);
  53             double nLastX( 0.0 );
  54             double nLastY( 0.0 );
  55             B2DPolygon aCurrPoly;
  56
  57             // skip initial whitespace
  58             basegfx::internal::skipSpaces(nPos, rSvgDStatement, nLen);
  59
  60             while(nPos < nLen)
  61             {
  62                 bool bRelative(false);
  63                 const sal_Unicode aCurrChar(rSvgDStatement[nPos]);
  64
  65                 if(o_rPolyPolygon.count() && !aCurrPoly.count() && !(aCurrChar == 'm' || aCurrChar == 'M'))
  66                 {
  67                     // we have a new sub-polygon starting, but without a 'moveto' command.
  68                     // this requires to add the current point as start point to the polygon
  69                     // (see SVG1.1 8.3.3 The "closepath" command)
  70                     aCurrPoly.append(B2DPoint(nLastX, nLastY));
  71                 }
  72
  73                 switch(aCurrChar)
  74                 {
  75                     case 'z' :
  76                     case 'Z' :
  77                     {
  78                         // consume CurrChar and whitespace
  79                         nPos++;
  80                         basegfx::internal::skipSpaces(nPos, rSvgDStatement, nLen);
  81
  82                         // create closed polygon and reset import values
  83                         if(aCurrPoly.count())
  84                         {
  85                             if(!bHandleRelativeNextPointCompatible)
  86                             {
  87                                 // SVG defines that "the next subpath starts at the
  88                                 // same initial point as the current subpath", so set the
  89                                 // current point if we do not need to be compatible
  90                                 nLastX = aCurrPoly.getB2DPoint(0).getX();
  91                                 nLastY = aCurrPoly.getB2DPoint(0).getY();
  92                             }
  93
  94                             aCurrPoly.setClosed(true);
  95                             o_rPolyPolygon.append(aCurrPoly);
  96                             aCurrPoly.clear();
  97                         }
  98
  99                         break;
 100                     }
 101
 102                     case 'm' :
 103                     case 'M' :
 104                     {
 105                         // create non-closed polygon and reset import values
 106                         if(aCurrPoly.count())
 107                         {
 108                             o_rPolyPolygon.append(aCurrPoly);
 109                             aCurrPoly.clear();
 110                         }
 111                         SAL_FALLTHROUGH; // to add coordinate data as 1st point of new polygon
 112                     }
 113                     case 'l' :
 114                     case 'L' :
 115                     {
 116                         if(aCurrChar == 'm' || aCurrChar == 'l')
 117                         {
 118                             bRelative = true;
 119                         }
 120
 121                         // consume CurrChar and whitespace
 122                         nPos++;
 123                         basegfx::internal::skipSpaces(nPos, rSvgDStatement, nLen);
 124
 125                         while(nPos < nLen && basegfx::internal::isOnNumberChar(rSvgDStatement, nPos))
 126                         {
 127                             double nX, nY;
 128
 129                             if(!basegfx::internal::importDoubleAndSpaces(nX, nPos, rSvgDStatement, nLen)) return false;
 130                             if(!basegfx::internal::importDoubleAndSpaces(nY, nPos, rSvgDStatement, nLen)) return false;
 131
 132                             if(bRelative)
 133                             {
 134                                 nX += nLastX;
 135                                 nY += nLastY;
 136                             }
 137
 138                             // set last position
 139                             nLastX = nX;
 140                             nLastY = nY;
 141
 142                             // add point
 143                             aCurrPoly.append(B2DPoint(nX, nY));
 144                         }
 145                         break;
 146                     }
 147
 148                     case 'h' :
 149                     {
 150                         bRelative = true;
 151                         SAL_FALLTHROUGH;
 152                     }
 153                     case 'H' :
 154                     {
 155                         nPos++;
 156                         basegfx::internal::skipSpaces(nPos, rSvgDStatement, nLen);
 157
 158                         while(nPos < nLen && basegfx::internal::isOnNumberChar(rSvgDStatement, nPos))
 159                         {
 160                             double nX, nY(nLastY);
 161
 162                             if(!basegfx::internal::importDoubleAndSpaces(nX, nPos, rSvgDStatement, nLen)) return false;
 163
 164                             if(bRelative)
 165                             {
 166                                 nX += nLastX;
 167                             }
 168
 169                             // set last position
 170                             nLastX = nX;
 171
 172                             // add point
 173                             aCurrPoly.append(B2DPoint(nX, nY));
 174                         }
 175                         break;
 176                     }
 177
 178                     case 'v' :
 179                     {
 180                         bRelative = true;
 181                         SAL_FALLTHROUGH;
 182                     }
 183                     case 'V' :
 184                     {
 185                         nPos++;
 186                         basegfx::internal::skipSpaces(nPos, rSvgDStatement, nLen);
 187
 188                         while(nPos < nLen && basegfx::internal::isOnNumberChar(rSvgDStatement, nPos))
 189                         {
 190                             double nX(nLastX), nY;
 191
 192                             if(!basegfx::internal::importDoubleAndSpaces(nY, nPos, rSvgDStatement, nLen)) return false;
 193
 194                             if(bRelative)
 195                             {
 196                                 nY += nLastY;
 197                             }
 198
 199                             // set last position
 200                             nLastY = nY;
 201
 202                             // add point
 203                             aCurrPoly.append(B2DPoint(nX, nY));
 204                         }
 205                         break;
 206                     }
 207
 208                     case 's' :
 209                     {
 210                         bRelative = true;
 211                         SAL_FALLTHROUGH;
 212                     }
 213                     case 'S' :
 214                     {
 215                         nPos++;
 216                         basegfx::internal::skipSpaces(nPos, rSvgDStatement, nLen);
 217
 218                         while(nPos < nLen && basegfx::internal::isOnNumberChar(rSvgDStatement, nPos))
 219                         {
 220                             double nX, nY;
 221                             double nX2, nY2;
 222
 223                             if(!basegfx::internal::importDoubleAndSpaces(nX2, nPos, rSvgDStatement, nLen)) return false;
 224                             if(!basegfx::internal::importDoubleAndSpaces(nY2, nPos, rSvgDStatement, nLen)) return false;
 225                             if(!basegfx::internal::importDoubleAndSpaces(nX, nPos, rSvgDStatement, nLen)) return false;
 226                             if(!basegfx::internal::importDoubleAndSpaces(nY, nPos, rSvgDStatement, nLen)) return false;
 227
 228                             if(bRelative)
 229                             {
 230                                 nX2 += nLastX;
 231                                 nY2 += nLastY;
 232                                 nX += nLastX;
 233                                 nY += nLastY;
 234                             }
 235
 236                             // ensure existence of start point
 237                             if(!aCurrPoly.count())
 238                             {
 239                                 aCurrPoly.append(B2DPoint(nLastX, nLastY));
 240                             }
 241
 242                             // get first control point. It's the reflection of the PrevControlPoint
 243                             // of the last point. If not existent, use current point (see SVG)
 244                             B2DPoint aPrevControl(B2DPoint(nLastX, nLastY));
 245                             const sal_uInt32 nIndex(aCurrPoly.count() - 1);
 246
 247                             if(aCurrPoly.areControlPointsUsed() && aCurrPoly.isPrevControlPointUsed(nIndex))
 248                             {
 249                                 const B2DPoint aPrevPoint(aCurrPoly.getB2DPoint(nIndex));
 250                                 const B2DPoint aPrevControlPoint(aCurrPoly.getPrevControlPoint(nIndex));
 251
 252                                 // use mirrored previous control point
 253                                 aPrevControl.setX((2.0 * aPrevPoint.getX()) - aPrevControlPoint.getX());
 254                                 aPrevControl.setY((2.0 * aPrevPoint.getY()) - aPrevControlPoint.getY());
 255                             }
 256
 257                             // append curved edge
 258                             aCurrPoly.appendBezierSegment(aPrevControl, B2DPoint(nX2, nY2), B2DPoint(nX, nY));
 259
 260                             // set last position
 261                             nLastX = nX;
 262                             nLastY = nY;
 263                         }
 264                         break;
 265                     }
 266
 267                     case 'c' :
 268                     {
 269                         bRelative = true;
 270                         SAL_FALLTHROUGH;
 271                     }
 272                     case 'C' :
 273                     {
 274                         nPos++;
 275                         basegfx::internal::skipSpaces(nPos, rSvgDStatement, nLen);
 276
 277                         while(nPos < nLen && basegfx::internal::isOnNumberChar(rSvgDStatement, nPos))
 278                         {
 279                             double nX, nY;
 280                             double nX1, nY1;
 281                             double nX2, nY2;
 282
 283                             if(!basegfx::internal::importDoubleAndSpaces(nX1, nPos, rSvgDStatement, nLen)) return false;
 284                             if(!basegfx::internal::importDoubleAndSpaces(nY1, nPos, rSvgDStatement, nLen)) return false;
 285                             if(!basegfx::internal::importDoubleAndSpaces(nX2, nPos, rSvgDStatement, nLen)) return false;
 286                             if(!basegfx::internal::importDoubleAndSpaces(nY2, nPos, rSvgDStatement, nLen)) return false;
 287                             if(!basegfx::internal::importDoubleAndSpaces(nX, nPos, rSvgDStatement, nLen)) return false;
 288                             if(!basegfx::internal::importDoubleAndSpaces(nY, nPos, rSvgDStatement, nLen)) return false;
 289
 290                             if(bRelative)
 291                             {
 292                                 nX1 += nLastX;
 293                                 nY1 += nLastY;
 294                                 nX2 += nLastX;
 295                                 nY2 += nLastY;
 296                                 nX += nLastX;
 297                                 nY += nLastY;
 298                             }
 299
 300                             // ensure existence of start point
 301                             if(!aCurrPoly.count())
 302                             {
 303                                 aCurrPoly.append(B2DPoint(nLastX, nLastY));
 304                             }
 305
 306                             // append curved edge
 307                             aCurrPoly.appendBezierSegment(B2DPoint(nX1, nY1), B2DPoint(nX2, nY2), B2DPoint(nX, nY));
 308
 309                             // set last position
 310                             nLastX = nX;
 311                             nLastY = nY;
 312                         }
 313                         break;
 314                     }
 315
 316                     // #100617# quadratic beziers are imported as cubic ones
 317                     case 'q' :
 318                     {
 319                         bRelative = true;
 320                         SAL_FALLTHROUGH;
 321                     }
 322                     case 'Q' :
 323                     {
 324                         nPos++;
 325                         basegfx::internal::skipSpaces(nPos, rSvgDStatement, nLen);
 326
 327                         while(nPos < nLen && basegfx::internal::isOnNumberChar(rSvgDStatement, nPos))
 328                         {
 329                             double nX, nY;
 330                             double nX1, nY1;
 331
 332                             if(!basegfx::internal::importDoubleAndSpaces(nX1, nPos, rSvgDStatement, nLen)) return false;
 333                             if(!basegfx::internal::importDoubleAndSpaces(nY1, nPos, rSvgDStatement, nLen)) return false;
 334                             if(!basegfx::internal::importDoubleAndSpaces(nX, nPos, rSvgDStatement, nLen)) return false;
 335                             if(!basegfx::internal::importDoubleAndSpaces(nY, nPos, rSvgDStatement, nLen)) return false;
 336
 337                             if(bRelative)
 338                             {
 339                                 nX1 += nLastX;
 340                                 nY1 += nLastY;
 341                                 nX += nLastX;
 342                                 nY += nLastY;
 343                             }
 344
 345                             // calculate the cubic bezier coefficients from the quadratic ones
 346                             const double nX1Prime((nX1 * 2.0 + nLastX) / 3.0);
 347                             const double nY1Prime((nY1 * 2.0 + nLastY) / 3.0);
 348                             const double nX2Prime((nX1 * 2.0 + nX) / 3.0);
 349                             const double nY2Prime((nY1 * 2.0 + nY) / 3.0);
 350
 351                             // ensure existence of start point
 352                             if(!aCurrPoly.count())
 353                             {
 354                                 aCurrPoly.append(B2DPoint(nLastX, nLastY));
 355                             }
 356
 357                             // append curved edge
 358                             aCurrPoly.appendBezierSegment(B2DPoint(nX1Prime, nY1Prime), B2DPoint(nX2Prime, nY2Prime), B2DPoint(nX, nY));
 359
 360                             // set last position
 361                             nLastX = nX;
 362                             nLastY = nY;
 363                         }
 364                         break;
 365                     }
 366
 367                     // #100617# relative quadratic beziers are imported as cubic
 368                     case 't' :
 369                     {
 370                         bRelative = true;
 371                         SAL_FALLTHROUGH;
 372                     }
 373                     case 'T' :
 374                     {
 375                         nPos++;
 376                         basegfx::internal::skipSpaces(nPos, rSvgDStatement, nLen);
 377
 378                         while(nPos < nLen && basegfx::internal::isOnNumberChar(rSvgDStatement, nPos))
 379                         {
 380                             double nX, nY;
 381
 382                             if(!basegfx::internal::importDoubleAndSpaces(nX, nPos, rSvgDStatement, nLen)) return false;
 383                             if(!basegfx::internal::importDoubleAndSpaces(nY, nPos, rSvgDStatement, nLen)) return false;
 384
 385                             if(bRelative)
 386                             {
 387                                 nX += nLastX;
 388                                 nY += nLastY;
 389                             }
 390
 391                             // ensure existence of start point
 392                             if(!aCurrPoly.count())
 393                             {
 394                                 aCurrPoly.append(B2DPoint(nLastX, nLastY));
 395                             }
 396
 397                             // get first control point. It's the reflection of the PrevControlPoint
 398                             // of the last point. If not existent, use current point (see SVG)
 399                             B2DPoint aPrevControl(B2DPoint(nLastX, nLastY));
 400                             const sal_uInt32 nIndex(aCurrPoly.count() - 1);
 401                             const B2DPoint aPrevPoint(aCurrPoly.getB2DPoint(nIndex));
 402
 403                             if(aCurrPoly.areControlPointsUsed() && aCurrPoly.isPrevControlPointUsed(nIndex))
 404                             {
 405                                 const B2DPoint aPrevControlPoint(aCurrPoly.getPrevControlPoint(nIndex));
 406
 407                                 // use mirrored previous control point
 408                                 aPrevControl.setX((2.0 * aPrevPoint.getX()) - aPrevControlPoint.getX());
 409                                 aPrevControl.setY((2.0 * aPrevPoint.getY()) - aPrevControlPoint.getY());
 410                             }
 411
 412                             if(!aPrevControl.equal(aPrevPoint))
 413                             {
 414                                 // there is a prev control point, and we have the already mirrored one
 415                                 // in aPrevControl. We also need the quadratic control point for this
 416                                 // new quadratic segment to calculate the 2nd cubic control point
 417                                 const B2DPoint aQuadControlPoint(
 418                                     ((3.0 * aPrevControl.getX()) - aPrevPoint.getX()) / 2.0,
 419                                     ((3.0 * aPrevControl.getY()) - aPrevPoint.getY()) / 2.0);
 420
 421                                 // calculate the cubic bezier coefficients from the quadratic ones.
 422                                 const double nX2Prime((aQuadControlPoint.getX() * 2.0 + nX) / 3.0);
 423                                 const double nY2Prime((aQuadControlPoint.getY() * 2.0 + nY) / 3.0);
 424
 425                                 // append curved edge, use mirrored cubic control point directly
 426                                 aCurrPoly.appendBezierSegment(aPrevControl, B2DPoint(nX2Prime, nY2Prime), B2DPoint(nX, nY));
 427                             }
 428                             else
 429                             {
 430                                 // when no previous control, SVG says to use current point -> straight line.
 431                                 // Just add end point
 432                                 aCurrPoly.append(B2DPoint(nX, nY));
 433                             }
 434
 435                             // set last position
 436                             nLastX = nX;
 437                             nLastY = nY;
 438                         }
 439                         break;
 440                     }
 441
 442                     case 'a' :
 443                     {
 444                         bRelative = true;
 445                         SAL_FALLTHROUGH;
 446                     }
 447                     case 'A' :
 448                     {
 449                         nPos++;
 450                         basegfx::internal::skipSpaces(nPos, rSvgDStatement, nLen);
 451
 452                         while(nPos < nLen && basegfx::internal::isOnNumberChar(rSvgDStatement, nPos))
 453                         {
 454                             double nX, nY;
 455                             double fRX, fRY, fPhi;
 456                             sal_Int32 bLargeArcFlag, bSweepFlag;
 457
 458                             if(!basegfx::internal::importDoubleAndSpaces(fRX, nPos, rSvgDStatement, nLen)) return false;
 459                             if(!basegfx::internal::importDoubleAndSpaces(fRY, nPos, rSvgDStatement, nLen)) return false;
 460                             if(!basegfx::internal::importDoubleAndSpaces(fPhi, nPos, rSvgDStatement, nLen)) return false;
 461                             if(!basegfx::internal::importFlagAndSpaces(bLargeArcFlag, nPos, rSvgDStatement, nLen)) return false;
 462                             if(!basegfx::internal::importFlagAndSpaces(bSweepFlag, nPos, rSvgDStatement, nLen)) return false;
 463                             if(!basegfx::internal::importDoubleAndSpaces(nX, nPos, rSvgDStatement, nLen)) return false;
 464                             if(!basegfx::internal::importDoubleAndSpaces(nY, nPos, rSvgDStatement, nLen)) return false;
 465
 466                             if(bRelative)
 467                             {
 468                                 nX += nLastX;
 469                                 nY += nLastY;
 470                             }
 471
 472                             if( rtl::math::approxEqual(nX, nLastX) && rtl::math::approxEqual(nY, nLastY) )
 473                                 continue; // start==end -> skip according to SVG spec
 474
 475                             if( fRX == 0.0 || fRY == 0.0 )
 476                             {
 477                                 // straight line segment according to SVG spec
 478                                 aCurrPoly.append(B2DPoint(nX, nY));
 479                             }
 480                             else
 481                             {
 482                                 // normalize according to SVG spec
 483                                 fRX=fabs(fRX); fRY=fabs(fRY);
 484
 485                                 // from the SVG spec, appendix F.6.4
 486
 487                                 // |x1'|   |cos phi   sin phi|  |(x1 - x2)/2|
 488                                 // |y1'| = |-sin phi  cos phi|  |(y1 - y2)/2|
 489                                 const B2DPoint p1(nLastX, nLastY);
 490                                 const B2DPoint p2(nX, nY);
 491                                 B2DHomMatrix aTransform(basegfx::utils::createRotateB2DHomMatrix(-fPhi*M_PI/180));
 492
 493                                 const B2DPoint p1_prime( aTransform * B2DPoint(((p1-p2)/2.0)) );
 494
 495                                 //           ______________________________________       rx y1'
 496                                 // |cx'|  + /  rx^2 ry^2 - rx^2 y1'^2 - ry^2 x1^2           ry
 497                                 // |cy'| =-/       rx^2y1'^2 + ry^2 x1'^2               - ry x1'
 498                                 //                                                          rx
 499                                 // chose + if f_A != f_S
 500                                 // chose - if f_A  = f_S
 501                                 B2DPoint aCenter_prime;
 502                                 const double fRadicant(
 503                                     (fRX*fRX*fRY*fRY - fRX*fRX*p1_prime.getY()*p1_prime.getY() - fRY*fRY*p1_prime.getX()*p1_prime.getX())/
 504                                     (fRX*fRX*p1_prime.getY()*p1_prime.getY() + fRY*fRY*p1_prime.getX()*p1_prime.getX()));
 505                                 if( fRadicant < 0.0 )
 506                                 {
 507                                     // no solution - according to SVG
 508                                     // spec, scale up ellipse
 509                                     // uniformly such that it passes
 510                                     // through end points (denominator
 511                                     // of radicant solved for fRY,
 512                                     // with s=fRX/fRY)
 513                                     const double fRatio(fRX/fRY);
 514                                     const double fRadicant2(
 515                                         p1_prime.getY()*p1_prime.getY() +
 516                                         p1_prime.getX()*p1_prime.getX()/(fRatio*fRatio));
 517                                     if( fRadicant2 < 0.0 )
 518                                     {
 519                                         // only trivial solution, one
 520                                         // of the axes 0 -> straight
 521                                         // line segment according to
 522                                         // SVG spec
 523                                         aCurrPoly.append(B2DPoint(nX, nY));
 524                                         continue;
 525                                     }
 526
 527                                     fRY=sqrt(fRadicant2);
 528                                     fRX=fRatio*fRY;
 529
 530                                     // keep center_prime forced to (0,0)
 531                                 }
 532                                 else
 533                                 {
 534                                     const double fFactor(
 535                                         (bLargeArcFlag==bSweepFlag ? -1.0 : 1.0) *
 536                                         sqrt(fRadicant));
 537
 538                                     // actually calculate center_prime
 539                                     aCenter_prime = B2DPoint(
 540                                         fFactor*fRX*p1_prime.getY()/fRY,
 541                                         -fFactor*fRY*p1_prime.getX()/fRX);
 542                                 }
 543
 544                                 //              +           u - v
 545                                 // angle(u,v) =  arccos( ------------ )     (take the sign of (ux vy - uy vx))
 546                                 //              -        ||u|| ||v||
 547
 548                                 //                  1    | (x1' - cx')/rx |
 549                                 // theta1 = angle((   ), |                | )
 550                                 //                  0    | (y1' - cy')/ry |
 551                                 const B2DPoint aRadii(fRX,fRY);
 552                                 double fTheta1(
 553                                     B2DVector(1.0,0.0).angle(
 554                                         (p1_prime-aCenter_prime)/aRadii));
 555
 556                                 //                 |1|    |  (-x1' - cx')/rx |
 557                                 // theta2 = angle( | | ,  |                  | )
 558                                 //                 |0|    |  (-y1' - cy')/ry |
 559                                 double fTheta2(
 560                                     B2DVector(1.0,0.0).angle(
 561                                         (-p1_prime-aCenter_prime)/aRadii));
 562
 563                                 // map both angles to [0,2pi)
 564                                 fTheta1 = fmod(2*M_PI+fTheta1,2*M_PI);
 565                                 fTheta2 = fmod(2*M_PI+fTheta2,2*M_PI);
 566
 567                                 // make sure the large arc is taken
 568                                 // (since
 569                                 // createPolygonFromEllipseSegment()
 570                                 // normalizes to e.g. cw arc)
 571                                 if( !bSweepFlag )
 572                                     std::swap(fTheta1,fTheta2);
 573
 574                                 // finally, create bezier polygon from this
 575                                 B2DPolygon aSegment(
 576                                     utils::createPolygonFromUnitEllipseSegment(
 577                                         fTheta1, fTheta2 ));
 578
 579                                 // transform ellipse by rotation & move to final center
 580                                 aTransform = basegfx::utils::createScaleB2DHomMatrix(fRX, fRY);
 581                                 aTransform.translate(aCenter_prime.getX(),
 582                                                      aCenter_prime.getY());
 583                                 aTransform.rotate(fPhi*M_PI/180);
 584                                 const B2DPoint aOffset((p1+p2)/2.0);
 585                                 aTransform.translate(aOffset.getX(),
 586                                                      aOffset.getY());
 587                                 aSegment.transform(aTransform);
 588
 589                                 // createPolygonFromEllipseSegment()
 590                                 // always creates arcs that are
 591                                 // positively oriented - flip polygon
 592                                 // if we swapped angles above
 593                                 if( !bSweepFlag )
 594                                     aSegment.flip();
 595
 596                                 // remember PointIndex of evtl. added pure helper points
 597                                 sal_uInt32 nPointIndex(aCurrPoly.count() + 1);
 598                                 aCurrPoly.append(aSegment);
 599
 600                                 // if asked for, mark pure helper points by adding them to the index list of
 601                                 // helper points
 602                                 if(pHelpPointIndexSet && aCurrPoly.count() > 1)
 603                                 {
 604                                     const sal_uInt32 nPolyIndex(o_rPolyPolygon.count());
 605
 606                                     for(;nPointIndex + 1 < aCurrPoly.count(); nPointIndex++)
 607                                     {
 608                                         pHelpPointIndexSet->insert(PointIndex(nPolyIndex, nPointIndex));
 609                                     }
 610                                 }
 611                             }
 612
 613                             // set last position
 614                             nLastX = nX;
 615                             nLastY = nY;
 616                         }
 617                         break;
 618                     }
 619
 620                     default:
 621                     {
 622                         SAL_WARN("basegfx", "importFromSvgD(): skipping tags in svg:d element (unknown: \""
 623                                 << aCurrChar
 624                                 << "\")!");
 625                         ++nPos;
 626                         break;
 627                     }
 628                 }
 629             }
 630
 631             // if there is polygon data, create non-closed polygon
 632             if(aCurrPoly.count())
 633             {
 634                 o_rPolyPolygon.append(aCurrPoly);
 635             }
 636
 637             return true;
 638         }
 639
 640         bool importFromSvgPoints( B2DPolygon&            o_rPoly,
 641                                   const OUString& rSvgPointsAttribute )
 642         {
 643             o_rPoly.clear();
 644             const sal_Int32 nLen(rSvgPointsAttribute.getLength());
 645             sal_Int32 nPos(0);
 646             double nX, nY;
 647
 648             // skip initial whitespace
 649             basegfx::internal::skipSpaces(nPos, rSvgPointsAttribute, nLen);
 650
 651             while(nPos < nLen)
 652             {
 653                 if(!basegfx::internal::importDoubleAndSpaces(nX, nPos, rSvgPointsAttribute, nLen)) return false;
 654                 if(!basegfx::internal::importDoubleAndSpaces(nY, nPos, rSvgPointsAttribute, nLen)) return false;
 655
 656                 // add point
 657                 o_rPoly.append(B2DPoint(nX, nY));
 658
 659                 // skip to next number, or finish
 660                 basegfx::internal::skipSpaces(nPos, rSvgPointsAttribute, nLen);
 661             }
 662
 663             return true;
 664         }
 665
 666         OUString exportToSvgPoints( const B2DPolygon& rPoly )
 667         {
 668             SAL_WARN_IF(rPoly.areControlPointsUsed(), "basegfx", "exportToSvgPoints: Only non-bezier polygons allowed (!)");
 669             const sal_uInt32 nPointCount(rPoly.count());
 670             OUStringBuffer aResult;
 671
 672             for(sal_uInt32 a(0); a < nPointCount; a++)
 673             {
 674                 const basegfx::B2DPoint aPoint(rPoly.getB2DPoint(a));
 675
 676                 if(a)
 677                 {
 678                     aResult.append(' ');
 679                 }
 680
 681                 aResult.append(aPoint.getX());
 682                 aResult.append(',');
 683                 aResult.append(aPoint.getY());
 684             }
 685
 686             return aResult.makeStringAndClear();
 687         }
 688
 689         OUString exportToSvgD(
 690             const B2DPolyPolygon& rPolyPolygon,
 691             bool bUseRelativeCoordinates,
 692             bool bDetectQuadraticBeziers,
 693             bool bHandleRelativeNextPointCompatible)
 694         {
 695             const sal_uInt32 nCount(rPolyPolygon.count());
 696             OUStringBuffer aResult;
 697             B2DPoint aCurrentSVGPosition(0.0, 0.0); // SVG assumes (0,0) as the initial current point
 698
 699             for(sal_uInt32 i(0); i < nCount; i++)
 700             {
 701                 const B2DPolygon aPolygon(rPolyPolygon.getB2DPolygon(i));
 702                 const sal_uInt32 nPointCount(aPolygon.count());
 703
 704                 if(nPointCount)
 705                 {
 706                     const bool bPolyUsesControlPoints(aPolygon.areControlPointsUsed());
 707                     const sal_uInt32 nEdgeCount(aPolygon.isClosed() ? nPointCount : nPointCount - 1);
 708                     sal_Unicode aLastSVGCommand(' '); // last SVG command char
 709                     B2DPoint aLeft, aRight; // for quadratic bezier test
 710
 711                     // handle polygon start point
 712                     B2DPoint aEdgeStart(aPolygon.getB2DPoint(0));
 713                     bool bUseRelativeCoordinatesForFirstPoint(bUseRelativeCoordinates);
 714
 715                     if(bHandleRelativeNextPointCompatible)
 716                     {
 717                         // To get around the error that the start point for the next polygon is the
 718                         // start point of the current one (and not the last as it was handled up to now)
 719                         // do force to write an absolute 'M' command as start for the next polygon
 720                         bUseRelativeCoordinatesForFirstPoint = false;
 721                     }
 722
 723                     // Write 'moveto' and the 1st coordinates, set aLastSVGCommand to 'lineto'
 724                     aResult.append(basegfx::internal::getCommand('M', 'm', bUseRelativeCoordinatesForFirstPoint));
 725                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeStart.getX(), aCurrentSVGPosition.getX(), bUseRelativeCoordinatesForFirstPoint);
 726                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeStart.getY(), aCurrentSVGPosition.getY(), bUseRelativeCoordinatesForFirstPoint);
 727                     aLastSVGCommand =  basegfx::internal::getCommand('L', 'l', bUseRelativeCoordinatesForFirstPoint);
 728                     aCurrentSVGPosition = aEdgeStart;
 729
 730                     for(sal_uInt32 nIndex(0); nIndex < nEdgeCount; nIndex++)
 731                     {
 732                         // prepare access to next point
 733                         const sal_uInt32 nNextIndex((nIndex + 1) % nPointCount);
 734                         const B2DPoint aEdgeEnd(aPolygon.getB2DPoint(nNextIndex));
 735
 736                         // handle edge from (aEdgeStart, aEdgeEnd) using indices (nIndex, nNextIndex)
 737                         const bool bEdgeIsBezier(bPolyUsesControlPoints
 738                             && (aPolygon.isNextControlPointUsed(nIndex) || aPolygon.isPrevControlPointUsed(nNextIndex)));
 739
 740                         if(bEdgeIsBezier)
 741                         {
 742                             // handle bezier edge
 743                             const B2DPoint aControlEdgeStart(aPolygon.getNextControlPoint(nIndex));
 744                             const B2DPoint aControlEdgeEnd(aPolygon.getPrevControlPoint(nNextIndex));
 745                             bool bIsQuadraticBezier(false);
 746
 747                             // check continuity at current edge's start point. For SVG, do NOT use an
 748                             // existing continuity since no 'S' or 's' statement should be written. At
 749                             // import, that 'previous' control vector is not available. SVG documentation
 750                             // says for interpretation:
 751
 752                             // "(If there is no previous command or if the previous command was
 753                             // not an C, c, S or s, assume the first control point is coincident
 754                             // with the current point.)"
 755
 756                             // That's what is done from our import, so avoid exporting it as first statement
 757                             // is necessary.
 758                             const bool bSymmetricAtEdgeStart(
 759                                 nIndex != 0
 760                                 && aPolygon.getContinuityInPoint(nIndex) == B2VectorContinuity::C2);
 761
 762                             if(bDetectQuadraticBeziers)
 763                             {
 764                                 // check for quadratic beziers - that's
 765                                 // the case if both control points are in
 766                                 // the same place when they are prolonged
 767                                 // to the common quadratic control point
 768
 769                                 // Left: P = (3P1 - P0) / 2
 770                                 // Right: P = (3P2 - P3) / 2
 771                                 aLeft = B2DPoint((3.0 * aControlEdgeStart - aEdgeStart) / 2.0);
 772                                 aRight= B2DPoint((3.0 * aControlEdgeEnd - aEdgeEnd) / 2.0);
 773                                 bIsQuadraticBezier = aLeft.equal(aRight);
 774                             }
 775
 776                             if(bIsQuadraticBezier)
 777                             {
 778                                 // approximately equal, export as quadratic bezier
 779                                 if(bSymmetricAtEdgeStart)
 780                                 {
 781                                     const sal_Unicode aCommand(basegfx::internal::getCommand('T', 't', bUseRelativeCoordinates));
 782
 783                                     if(aLastSVGCommand != aCommand)
 784                                     {
 785                                         aResult.append(aCommand);
 786                                     }
 787
 788                                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeEnd.getX(), aCurrentSVGPosition.getX(), bUseRelativeCoordinates);
 789                                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeEnd.getY(), aCurrentSVGPosition.getY(), bUseRelativeCoordinates);
 790                                     aLastSVGCommand = aCommand;
 791                                     aCurrentSVGPosition = aEdgeEnd;
 792                                 }
 793                                 else
 794                                 {
 795                                     const sal_Unicode aCommand(basegfx::internal::getCommand('Q', 'q', bUseRelativeCoordinates));
 796
 797                                     if(aLastSVGCommand != aCommand)
 798                                     {
 799                                         aResult.append(aCommand);
 800                                     }
 801
 802                                     basegfx::internal::putNumberCharWithSpace(aResult, aLeft.getX(), aCurrentSVGPosition.getX(), bUseRelativeCoordinates);
 803                                     basegfx::internal::putNumberCharWithSpace(aResult, aLeft.getY(), aCurrentSVGPosition.getY(), bUseRelativeCoordinates);
 804                                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeEnd.getX(), aCurrentSVGPosition.getX(), bUseRelativeCoordinates);
 805                                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeEnd.getY(), aCurrentSVGPosition.getY(), bUseRelativeCoordinates);
 806                                     aLastSVGCommand = aCommand;
 807                                     aCurrentSVGPosition = aEdgeEnd;
 808                                 }
 809                             }
 810                             else
 811                             {
 812                                 // export as cubic bezier
 813                                 if(bSymmetricAtEdgeStart)
 814                                 {
 815                                     const sal_Unicode aCommand(basegfx::internal::getCommand('S', 's', bUseRelativeCoordinates));
 816
 817                                     if(aLastSVGCommand != aCommand)
 818                                     {
 819                                         aResult.append(aCommand);
 820                                     }
 821
 822                                     basegfx::internal::putNumberCharWithSpace(aResult, aControlEdgeEnd.getX(), aCurrentSVGPosition.getX(), bUseRelativeCoordinates);
 823                                     basegfx::internal::putNumberCharWithSpace(aResult, aControlEdgeEnd.getY(), aCurrentSVGPosition.getY(), bUseRelativeCoordinates);
 824                                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeEnd.getX(), aCurrentSVGPosition.getX(), bUseRelativeCoordinates);
 825                                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeEnd.getY(), aCurrentSVGPosition.getY(), bUseRelativeCoordinates);
 826                                     aLastSVGCommand = aCommand;
 827                                     aCurrentSVGPosition = aEdgeEnd;
 828                                 }
 829                                 else
 830                                 {
 831                                     const sal_Unicode aCommand(basegfx::internal::getCommand('C', 'c', bUseRelativeCoordinates));
 832
 833                                     if(aLastSVGCommand != aCommand)
 834                                     {
 835                                         aResult.append(aCommand);
 836                                     }
 837
 838                                     basegfx::internal::putNumberCharWithSpace(aResult, aControlEdgeStart.getX(), aCurrentSVGPosition.getX(), bUseRelativeCoordinates);
 839                                     basegfx::internal::putNumberCharWithSpace(aResult, aControlEdgeStart.getY(), aCurrentSVGPosition.getY(), bUseRelativeCoordinates);
 840                                     basegfx::internal::putNumberCharWithSpace(aResult, aControlEdgeEnd.getX(), aCurrentSVGPosition.getX(), bUseRelativeCoordinates);
 841                                     basegfx::internal::putNumberCharWithSpace(aResult, aControlEdgeEnd.getY(), aCurrentSVGPosition.getY(), bUseRelativeCoordinates);
 842                                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeEnd.getX(), aCurrentSVGPosition.getX(), bUseRelativeCoordinates);
 843                                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeEnd.getY(), aCurrentSVGPosition.getY(), bUseRelativeCoordinates);
 844                                     aLastSVGCommand = aCommand;
 845                                     aCurrentSVGPosition = aEdgeEnd;
 846                                 }
 847                             }
 848                         }
 849                         else
 850                         {
 851                             // straight edge
 852                             if(nNextIndex == 0)
 853                             {
 854                                 // it's a closed polygon's last edge and it's not a bezier edge, so there is
 855                                 // no need to write it
 856                             }
 857                             else
 858                             {
 859                                 const bool bXEqual(rtl::math::approxEqual(aEdgeStart.getX(), aEdgeEnd.getX()));
 860                                 const bool bYEqual(rtl::math::approxEqual(aEdgeStart.getY(), aEdgeEnd.getY()));
 861
 862                                 if(bXEqual && bYEqual)
 863                                 {
 864                                     // point is a double point; do not export at all
 865                                 }
 866                                 else if(bXEqual)
 867                                 {
 868                                     // export as vertical line
 869                                     const sal_Unicode aCommand(basegfx::internal::getCommand('V', 'v', bUseRelativeCoordinates));
 870
 871                                     if(aLastSVGCommand != aCommand)
 872                                     {
 873                                         aResult.append(aCommand);
 874                                         aLastSVGCommand = aCommand;
 875                                     }
 876
 877                                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeEnd.getY(), aCurrentSVGPosition.getY(), bUseRelativeCoordinates);
 878                                     aCurrentSVGPosition = aEdgeEnd;
 879                                 }
 880                                 else if(bYEqual)
 881                                 {
 882                                     // export as horizontal line
 883                                     const sal_Unicode aCommand(basegfx::internal::getCommand('H', 'h', bUseRelativeCoordinates));
 884
 885                                     if(aLastSVGCommand != aCommand)
 886                                     {
 887                                         aResult.append(aCommand);
 888                                         aLastSVGCommand = aCommand;
 889                                     }
 890
 891                                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeEnd.getX(), aCurrentSVGPosition.getX(), bUseRelativeCoordinates);
 892                                     aCurrentSVGPosition = aEdgeEnd;
 893                                 }
 894                                 else
 895                                 {
 896                                     // export as line
 897                                     const sal_Unicode aCommand(basegfx::internal::getCommand('L', 'l', bUseRelativeCoordinates));
 898
 899                                     if(aLastSVGCommand != aCommand)
 900                                     {
 901                                         aResult.append(aCommand);
 902                                         aLastSVGCommand = aCommand;
 903                                     }
 904
 905                                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeEnd.getX(), aCurrentSVGPosition.getX(), bUseRelativeCoordinates);
 906                                     basegfx::internal::putNumberCharWithSpace(aResult, aEdgeEnd.getY(), aCurrentSVGPosition.getY(), bUseRelativeCoordinates);
 907                                     aCurrentSVGPosition = aEdgeEnd;
 908                                 }
 909                             }
 910                         }
 911
 912                         // prepare edge start for next loop step
 913                         aEdgeStart = aEdgeEnd;
 914                     }
 915
 916                     // close path if closed poly (Z and z are equivalent here, but looks nicer when case is matched)
 917                     if(aPolygon.isClosed())
 918                     {
 919                         aResult.append(basegfx::internal::getCommand('Z', 'z', bUseRelativeCoordinates));
 920                     }
 921
 922                     if(!bHandleRelativeNextPointCompatible)
 923                     {
 924                         // SVG defines that "the next subpath starts at the same initial point as the current subpath",
 925                         // so set aCurrentSVGPosition to the 1st point of the current, now ended and written path
 926                         aCurrentSVGPosition = aPolygon.getB2DPoint(0);
 927                     }
 928                 }
 929             }
 930
 931             return aResult.makeStringAndClear();
 932         }
 933     }
 934 }
 935
 936 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */