contrib/src/ogl/ogldiag.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        ogldiag.cpp
   3 // Purpose:     wxDiagram
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     12/07/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifdef __GNUG__
  13 #pragma implementation "ogldiag.h"
  14 #endif
  15
  16 // For compilers that support precompilation, includes "wx.h".
  17 #include "wx/wxprec.h"
  18
  19 #ifdef __BORLANDC__
  20 #pragma hdrstop
  21 #endif
  22
  23 #ifndef WX_PRECOMP
  24 #include <wx/wx.h>
  25 #endif
  26
  27 #include <wx/deprecated/wxexpr.h>
  28
  29 #ifdef new
  30 #undef new
  31 #endif
  32
  33 #include <ctype.h>
  34 #include <math.h>
  35 #include <stdlib.h>
  36
  37 #include <wx/ogl/basic.h>
  38 #include <wx/ogl/basicp.h>
  39 #include <wx/ogl/canvas.h>
  40 #include <wx/ogl/ogldiag.h>
  41 #include <wx/ogl/lines.h>
  42 #include <wx/ogl/composit.h>
  43 #include <wx/ogl/misc.h>
  44
  45 IMPLEMENT_DYNAMIC_CLASS(wxDiagram, wxObject)
  46
  47 // Object canvas
  48 wxDiagram::wxDiagram()
  49 {
  50   m_diagramCanvas = NULL;
  51   m_quickEditMode = FALSE;
  52   m_snapToGrid = TRUE;
  53   m_gridSpacing = 5.0;
  54   m_shapeList = new wxList;
  55   m_mouseTolerance = DEFAULT_MOUSE_TOLERANCE;
  56 }
  57
  58 wxDiagram::~wxDiagram()
  59 {
  60   if (m_shapeList)
  61     delete m_shapeList;
  62 }
  63
  64 void wxDiagram::SetSnapToGrid(bool snap)
  65 {
  66   m_snapToGrid = snap;
  67 }
  68
  69 void wxDiagram::SetGridSpacing(double spacing)
  70 {
  71   m_gridSpacing = spacing;
  72 }
  73
  74 void wxDiagram::Snap(double *x, double *y)
  75 {
  76   if (m_snapToGrid)
  77   {
  78     *x = m_gridSpacing * ((int)(*x/m_gridSpacing + 0.5));
  79     *y = m_gridSpacing * ((int)(*y/m_gridSpacing + 0.5));
  80   }
  81 }
  82
  83
  84 void wxDiagram::Redraw(wxDC& dc)
  85 {
  86   if (m_shapeList)
  87   {
  88     if (GetCanvas())
  89       GetCanvas()->SetCursor(* wxHOURGLASS_CURSOR);
  90     wxNode *current = m_shapeList->GetFirst();
  91
  92     while (current)
  93     {
  94       wxShape *object = (wxShape *)current->GetData();
  95       if (!object->GetParent())
  96         object->Draw(dc);
  97
  98       current = current->GetNext();
  99     }
 100     if (GetCanvas())
 101       GetCanvas()->SetCursor(* wxSTANDARD_CURSOR);
 102   }
 103 }
 104
 105 void wxDiagram::Clear(wxDC& dc)
 106 {
 107   dc.Clear();
 108 }
 109
 110 // Insert object after addAfter, or at end of list.
 111 void wxDiagram::AddShape(wxShape *object, wxShape *addAfter)
 112 {
 113   wxNode *nodeAfter = NULL;
 114   if (addAfter)
 115     nodeAfter = m_shapeList->Member(addAfter);
 116
 117   if (!m_shapeList->Member(object))
 118   {
 119     if (nodeAfter)
 120     {
 121       if (nodeAfter->GetNext())
 122         m_shapeList->Insert(nodeAfter->GetNext(), object);
 123       else
 124         m_shapeList->Append(object);
 125     }
 126     else
 127       m_shapeList->Append(object);
 128     object->SetCanvas(GetCanvas());
 129   }
 130 }
 131
 132 void wxDiagram::InsertShape(wxShape *object)
 133 {
 134   m_shapeList->Insert(object);
 135   object->SetCanvas(GetCanvas());
 136 }
 137
 138 void wxDiagram::RemoveShape(wxShape *object)
 139 {
 140   m_shapeList->DeleteObject(object);
 141 }
 142
 143 // Should this delete the actual objects too? I think not.
 144 void wxDiagram::RemoveAllShapes()
 145 {
 146   m_shapeList->Clear();
 147 }
 148
 149 void wxDiagram::DeleteAllShapes()
 150 {
 151   wxNode *node = m_shapeList->GetFirst();
 152   while (node)
 153   {
 154     wxShape *shape = (wxShape *)node->GetData();
 155     if (!shape->GetParent())
 156     {
 157       RemoveShape(shape);
 158       delete shape;
 159       node = m_shapeList->GetFirst();
 160     }
 161     else
 162       node = node->GetNext();
 163   }
 164 }
 165
 166 void wxDiagram::ShowAll(bool show)
 167 {
 168   wxNode *current = m_shapeList->GetFirst();
 169
 170   while (current)
 171   {
 172     wxShape *object = (wxShape *)current->GetData();
 173     object->Show(show);
 174
 175     current = current->GetNext();
 176   }
 177 }
 178
 179 void wxDiagram::DrawOutline(wxDC& dc, double x1, double y1, double x2, double y2)
 180 {
 181   wxPen dottedPen(wxColour(0, 0, 0), 1, wxDOT);
 182   dc.SetPen(dottedPen);
 183   dc.SetBrush((* wxTRANSPARENT_BRUSH));
 184
 185   wxPoint points[5];
 186
 187   points[0].x = (int) x1;
 188   points[0].y = (int) y1;
 189
 190   points[1].x = (int) x2;
 191   points[1].y = (int) y1;
 192
 193   points[2].x = (int) x2;
 194   points[2].y = (int) y2;
 195
 196   points[3].x = (int) x1;
 197   points[3].y = (int) y2;
 198
 199   points[4].x = (int) x1;
 200   points[4].y = (int) y1;
 201   dc.DrawLines(5, points);
 202 }
 203
 204 // Make sure all text that should be centred, is centred.
 205 void wxDiagram::RecentreAll(wxDC& dc)
 206 {
 207   wxNode *object_node = m_shapeList->GetFirst();
 208   while (object_node)
 209   {
 210     wxShape *obj = (wxShape *)object_node->GetData();
 211     obj->Recentre(dc);
 212     object_node = object_node->GetNext();
 213   }
 214 }
 215
 216 // Input/output
 217 #if wxUSE_PROLOGIO
 218 bool wxDiagram::SaveFile(const wxString& filename)
 219 {
 220   wxBeginBusyCursor();
 221
 222   wxExprDatabase *database = new wxExprDatabase;
 223
 224   // First write the diagram type
 225   wxExpr *header = new wxExpr("diagram");
 226   OnHeaderSave(*database, *header);
 227
 228   database->Append(header);
 229
 230   wxNode *node = m_shapeList->GetFirst();
 231   while (node)
 232   {
 233     wxShape *shape = (wxShape *)node->GetData();
 234
 235     if (!shape->IsKindOf(CLASSINFO(wxControlPoint)))
 236     {
 237       wxExpr *expr = NULL;
 238       if (shape->IsKindOf(CLASSINFO(wxLineShape)))
 239         expr = new wxExpr("line");
 240        else
 241         expr = new wxExpr("shape");
 242
 243       OnShapeSave(*database, *shape, *expr);
 244     }
 245     node = node->Next();
 246   }
 247   OnDatabaseSave(*database);
 248
 249   wxString tempFile;
 250   wxGetTempFileName(wxT("diag"), tempFile);
 251   FILE* file = fopen(tempFile.mb_str(wxConvFile), "w");
 252   if (! file)
 253   {
 254     wxEndBusyCursor();
 255     delete database;
 256     return FALSE;
 257   }
 258
 259   database->Write(file);
 260   fclose(file);
 261   delete database;
 262
 263 /*
 264   // Save backup
 265   if (FileExists(filename))
 266   {
 267     char buf[400];
 268 #ifdef __X__
 269     sprintf(buf, "%s.bak", filename);
 270 #endif
 271 #ifdef __WXMSW__
 272     sprintf(buf, "_diagram.bak");
 273 #endif
 274     if (FileExists(buf)) wxRemoveFile(buf);
 275     if (!wxRenameFile(filename, buf))
 276     {
 277       wxCopyFile(filename, buf);
 278       wxRemoveFile(filename);
 279     }
 280   }
 281 */
 282
 283   // Copy the temporary file to the correct filename
 284   if (!wxRenameFile(tempFile, filename))
 285   {
 286     wxCopyFile(tempFile, filename);
 287     wxRemoveFile(tempFile);
 288   }
 289
 290   wxEndBusyCursor();
 291   return TRUE;
 292 }
 293
 294 bool wxDiagram::LoadFile(const wxString& filename)
 295 {
 296   wxBeginBusyCursor();
 297
 298   wxExprDatabase database(wxExprInteger, "id");
 299   if (!database.Read(filename))
 300   {
 301     wxEndBusyCursor();
 302     return FALSE;
 303   }
 304
 305   DeleteAllShapes();
 306
 307   database.BeginFind();
 308   wxExpr *header = database.FindClauseByFunctor("diagram");
 309
 310   if (header)
 311     OnHeaderLoad(database, *header);
 312
 313   // Scan through all clauses and register the ids
 314   wxNode *node = database.First();
 315   while (node)
 316   {
 317     wxExpr *clause = (wxExpr *)node->GetData();
 318     long id = -1;
 319     clause->GetAttributeValue("id", id);
 320     wxRegisterId(id);
 321     node = node->Next();
 322   }
 323
 324   ReadNodes(database);
 325   ReadContainerGeometry(database);
 326   ReadLines(database);
 327
 328   OnDatabaseLoad(database);
 329
 330   wxEndBusyCursor();
 331
 332   return TRUE;
 333 }
 334
 335 void wxDiagram::ReadNodes(wxExprDatabase& database)
 336 {
 337   // Find and create the node images
 338   database.BeginFind();
 339   wxExpr *clause = database.FindClauseByFunctor("shape");
 340   while (clause)
 341   {
 342     wxChar *type = NULL;
 343     long parentId = -1;
 344
 345     clause->AssignAttributeValue(wxT("type"), &type);
 346     clause->AssignAttributeValue(wxT("parent"), &parentId);
 347     wxClassInfo *classInfo = wxClassInfo::FindClass(type);
 348     if (classInfo)
 349     {
 350       wxShape *shape = (wxShape *)classInfo->CreateObject();
 351       OnShapeLoad(database, *shape, *clause);
 352
 353       shape->SetCanvas(GetCanvas());
 354       shape->Show(TRUE);
 355
 356       m_shapeList->Append(shape);
 357
 358       // If child of composite, link up
 359       if (parentId > -1)
 360       {
 361         wxExpr *parentExpr = database.HashFind("shape", parentId);
 362         if (parentExpr && parentExpr->GetClientData())
 363         {
 364           wxShape *parent = (wxShape *)parentExpr->GetClientData();
 365           shape->SetParent(parent);
 366           parent->GetChildren().Append(shape);
 367         }
 368       }
 369
 370       clause->SetClientData(shape);
 371     }
 372     if (type)
 373       delete[] type;
 374
 375     clause = database.FindClauseByFunctor("shape");
 376   }
 377   return;
 378 }
 379
 380 void wxDiagram::ReadLines(wxExprDatabase& database)
 381 {
 382   database.BeginFind();
 383   wxExpr *clause = database.FindClauseByFunctor("line");
 384   while (clause)
 385   {
 386     wxString type;
 387     long parentId = -1;
 388
 389     clause->GetAttributeValue("type", type);
 390     clause->GetAttributeValue("parent", parentId);
 391     wxClassInfo *classInfo = wxClassInfo::FindClass(type);
 392     if (classInfo)
 393     {
 394       wxLineShape *shape = (wxLineShape *)classInfo->CreateObject();
 395       shape->Show(TRUE);
 396
 397       OnShapeLoad(database, *shape, *clause);
 398       shape->SetCanvas(GetCanvas());
 399
 400       long image_to = -1; long image_from = -1;
 401       clause->GetAttributeValue("to", image_to);
 402       clause->GetAttributeValue("from", image_from);
 403
 404       wxExpr *image_to_expr = database.HashFind("shape", image_to);
 405
 406       if (!image_to_expr)
 407       {
 408         // Error
 409       }
 410       wxExpr *image_from_expr = database.HashFind("shape", image_from);
 411
 412       if (!image_from_expr)
 413       {
 414         // Error
 415       }
 416
 417       if (image_to_expr && image_from_expr)
 418       {
 419         wxShape *image_to_object = (wxShape *)image_to_expr->GetClientData();
 420         wxShape *image_from_object = (wxShape *)image_from_expr->GetClientData();
 421
 422         if (image_to_object && image_from_object)
 423         {
 424           image_from_object->AddLine(shape, image_to_object, shape->GetAttachmentFrom(), shape->GetAttachmentTo());
 425         }
 426       }
 427       clause->SetClientData(shape);
 428
 429       m_shapeList->Append(shape);
 430     }
 431
 432     clause = database.FindClauseByFunctor("line");
 433   }
 434 }
 435
 436 // Containers have divisions that reference adjoining divisions,
 437 // so we need a separate pass to link everything up.
 438 // Also used by Symbol Library.
 439 void wxDiagram::ReadContainerGeometry(wxExprDatabase& database)
 440 {
 441   database.BeginFind();
 442   wxExpr *clause = database.FindClauseByFunctor("shape");
 443   while (clause)
 444   {
 445     wxShape *image = (wxShape *)clause->GetClientData();
 446     if (image && image->IsKindOf(CLASSINFO(wxCompositeShape)))
 447     {
 448       wxCompositeShape *composite = (wxCompositeShape *)image;
 449       wxExpr *divisionExpr = NULL;
 450
 451       // Find the list of divisions in the composite
 452       clause->GetAttributeValue("divisions", &divisionExpr);
 453       if (divisionExpr)
 454       {
 455         int i = 0;
 456         wxExpr *idExpr = divisionExpr->Nth(i);
 457         while (idExpr)
 458         {
 459           long divisionId = idExpr->IntegerValue();
 460           wxExpr *childExpr = database.HashFind("shape", divisionId);
 461           if (childExpr && childExpr->GetClientData())
 462           {
 463             wxDivisionShape *child = (wxDivisionShape *)childExpr->GetClientData();
 464             composite->GetDivisions().Append(child);
 465
 466             // Find the adjoining shapes
 467             long leftSideId = -1;
 468             long topSideId = -1;
 469             long rightSideId = -1;
 470             long bottomSideId = -1;
 471             childExpr->GetAttributeValue("left_side", leftSideId);
 472             childExpr->GetAttributeValue("top_side", topSideId);
 473             childExpr->GetAttributeValue("right_side", rightSideId);
 474             childExpr->GetAttributeValue("bottom_side", bottomSideId);
 475             if (leftSideId > -1)
 476             {
 477               wxExpr *leftExpr = database.HashFind("shape", leftSideId);
 478               if (leftExpr && leftExpr->GetClientData())
 479               {
 480                 wxDivisionShape *leftSide = (wxDivisionShape *)leftExpr->GetClientData();
 481                 child->SetLeftSide(leftSide);
 482               }
 483             }
 484             if (topSideId > -1)
 485             {
 486               wxExpr *topExpr = database.HashFind("shape", topSideId);
 487               if (topExpr && topExpr->GetClientData())
 488               {
 489                 wxDivisionShape *topSide = (wxDivisionShape *)topExpr->GetClientData();
 490                 child->SetTopSide(topSide);
 491               }
 492             }
 493             if (rightSideId > -1)
 494             {
 495               wxExpr *rightExpr = database.HashFind("shape", rightSideId);
 496               if (rightExpr && rightExpr->GetClientData())
 497               {
 498                 wxDivisionShape *rightSide = (wxDivisionShape *)rightExpr->GetClientData();
 499                 child->SetRightSide(rightSide);
 500               }
 501             }
 502             if (bottomSideId > -1)
 503             {
 504               wxExpr *bottomExpr = database.HashFind("shape", bottomSideId);
 505               if (bottomExpr && bottomExpr->GetClientData())
 506               {
 507                 wxDivisionShape *bottomSide = (wxDivisionShape *)bottomExpr->GetClientData();
 508                 child->SetBottomSide(bottomSide);
 509               }
 510             }
 511           }
 512           i ++;
 513           idExpr = divisionExpr->Nth(i);
 514         }
 515       }
 516     }
 517
 518     clause = database.FindClauseByFunctor("shape");
 519   }
 520 }
 521
 522 // Allow for modifying file
 523 bool wxDiagram::OnDatabaseLoad(wxExprDatabase& db)
 524 {
 525   return TRUE;
 526 }
 527
 528 bool wxDiagram::OnDatabaseSave(wxExprDatabase& db)
 529 {
 530   return TRUE;
 531 }
 532
 533 bool wxDiagram::OnShapeSave(wxExprDatabase& db, wxShape& shape, wxExpr& expr)
 534 {
 535   shape.WriteAttributes(&expr);
 536   db.Append(&expr);
 537
 538   if (shape.IsKindOf(CLASSINFO(wxCompositeShape)))
 539   {
 540     wxNode *node = shape.GetChildren().First();
 541     while (node)
 542     {
 543       wxShape *childShape = (wxShape *)node->GetData();
 544       wxExpr *childExpr = new wxExpr("shape");
 545       OnShapeSave(db, *childShape, *childExpr);
 546       node = node->Next();
 547     }
 548   }
 549
 550   return TRUE;
 551 }
 552
 553 bool wxDiagram::OnShapeLoad(wxExprDatabase& db, wxShape& shape, wxExpr& expr)
 554 {
 555   shape.ReadAttributes(&expr);
 556   return TRUE;
 557 }
 558
 559 bool wxDiagram::OnHeaderSave(wxExprDatabase& db, wxExpr& expr)
 560 {
 561   return TRUE;
 562 }
 563
 564 bool wxDiagram::OnHeaderLoad(wxExprDatabase& db, wxExpr& expr)
 565 {
 566   return TRUE;
 567 }
 568
 569 #endif
 570
 571 void wxDiagram::SetCanvas(wxShapeCanvas *can)
 572 {
 573   m_diagramCanvas = can;
 574 }
 575
 576 // Find a shape by its id
 577 wxShape* wxDiagram::FindShape(long id) const
 578 {
 579     wxNode* node = GetShapeList()->GetFirst();
 580     while (node)
 581     {
 582         wxShape* shape = (wxShape*) node->GetData();
 583         if (shape->GetId() == id)
 584             return shape;
 585         node = node->GetNext();
 586     }
 587     return NULL;
 588 }
 589
 590
 591 //// Crossings classes
 592
 593 wxLineCrossings::wxLineCrossings()
 594 {
 595 }
 596
 597 wxLineCrossings::~wxLineCrossings()
 598 {
 599     ClearCrossings();
 600 }
 601
 602 void wxLineCrossings::FindCrossings(wxDiagram& diagram)
 603 {
 604     ClearCrossings();
 605     wxNode* node1 = diagram.GetShapeList()->GetFirst();
 606     while (node1)
 607     {
 608         wxShape* shape1 = (wxShape*) node1->GetData();
 609         if (shape1->IsKindOf(CLASSINFO(wxLineShape)))
 610         {
 611             wxLineShape* lineShape1 = (wxLineShape*) shape1;
 612             // Iterate through the segments
 613             wxList* pts1 = lineShape1->GetLineControlPoints();
 614             int i;
 615             for (i = 0; i < (pts1->GetCount() - 1); i++)
 616             {
 617                 wxRealPoint* pt1_a = (wxRealPoint*) (pts1->Item(i)->GetData());
 618                 wxRealPoint* pt1_b = (wxRealPoint*) (pts1->Item(i+1)->GetData());
 619
 620                 // Now we iterate through the segments again
 621
 622                 wxNode* node2 = diagram.GetShapeList()->GetFirst();
 623                 while (node2)
 624                 {
 625                     wxShape* shape2 = (wxShape*) node2->GetData();
 626
 627                     // Assume that the same line doesn't cross itself
 628                     if (shape2->IsKindOf(CLASSINFO(wxLineShape)) && (shape1 != shape2))
 629                     {
 630                         wxLineShape* lineShape2 = (wxLineShape*) shape2;
 631                         // Iterate through the segments
 632                         wxList* pts2 = lineShape2->GetLineControlPoints();
 633                         int j;
 634                         for (j = 0; j < (pts2->GetCount() - 1); j++)
 635                         {
 636                             wxRealPoint* pt2_a = (wxRealPoint*) (pts2->Item(j)->GetData());
 637                             wxRealPoint* pt2_b = (wxRealPoint*) (pts2->Item(j+1)->GetData());
 638
 639                             // Now let's see if these two segments cross.
 640                             double ratio1, ratio2;
 641                             oglCheckLineIntersection(pt1_a->x, pt1_a->y, pt1_b->x, pt1_b->y,
 642                                pt2_a->x, pt2_a->y, pt2_b->x, pt2_b->y,
 643                              & ratio1, & ratio2);
 644
 645                             if ((ratio1 < 1.0) && (ratio1 > -1.0))
 646                             {
 647                                 // Intersection!
 648                                 wxLineCrossing* crossing = new wxLineCrossing;
 649                                 crossing->m_intersect.x = (pt1_a->x + (pt1_b->x - pt1_a->x)*ratio1);
 650                                 crossing->m_intersect.y = (pt1_a->y + (pt1_b->y - pt1_a->y)*ratio1);
 651
 652                                 crossing->m_pt1 = * pt1_a;
 653                                 crossing->m_pt2 = * pt1_b;
 654                                 crossing->m_pt3 = * pt2_a;
 655                                 crossing->m_pt4 = * pt2_b;
 656
 657                                 crossing->m_lineShape1 = lineShape1;
 658                                 crossing->m_lineShape2 = lineShape2;
 659
 660                                 m_crossings.Append(crossing);
 661                             }
 662                         }
 663                     }
 664                     node2 = node2->GetNext();
 665                 }
 666             }
 667         }
 668
 669         node1 = node1->GetNext();
 670     }
 671 }
 672
 673 void wxLineCrossings::DrawCrossings(wxDiagram& diagram, wxDC& dc)
 674 {
 675     dc.SetBrush(*wxTRANSPARENT_BRUSH);
 676
 677     long arcWidth = 8;
 678
 679     wxNode* node = m_crossings.GetFirst();
 680     while (node)
 681     {
 682         wxLineCrossing* crossing = (wxLineCrossing*) node->GetData();
 683 //        dc.DrawEllipse((long) (crossing->m_intersect.x - (arcWidth/2.0) + 0.5), (long) (crossing->m_intersect.y - (arcWidth/2.0) + 0.5),
 684 //           arcWidth, arcWidth);
 685
 686
 687         // Let's do some geometry to find the points on either end of the arc.
 688 /*
 689
 690 (x1, y1)
 691     |\
 692     | \
 693     |  \
 694     |   \
 695     |    \
 696     |    |\ c    c1
 697     |  a | \
 698          |  \
 699     |     -  x <-- centre of arc
 700  a1 |     b  |\
 701     |        | \ c2
 702     |     a2 |  \
 703     |         -  \
 704     |         b2  \
 705     |              \
 706     |_______________\ (x2, y2)
 707           b1
 708
 709 */
 710
 711         double a1 = wxMax(crossing->m_pt1.y, crossing->m_pt2.y) - wxMin(crossing->m_pt1.y, crossing->m_pt2.y) ;
 712         double b1 = wxMax(crossing->m_pt1.x, crossing->m_pt2.x) - wxMin(crossing->m_pt1.x, crossing->m_pt2.x) ;
 713         double c1 = sqrt( (a1*a1) + (b1*b1) );
 714
 715         double c = arcWidth / 2.0;
 716         double a = c * a1/c1 ;
 717         double b = c * b1/c1 ;
 718
 719         // I'm not sure this is right, since we don't know which direction we should be going in - need
 720         // to know which way the line slopes and choose the sign appropriately.
 721         double arcX1 = crossing->m_intersect.x - b;
 722         double arcY1 = crossing->m_intersect.y - a;
 723
 724         double arcX2 = crossing->m_intersect.x + b;
 725         double arcY2 = crossing->m_intersect.y + a;
 726
 727         dc.SetPen(*wxBLACK_PEN);
 728         dc.DrawArc( (long) arcX1, (long) arcY1, (long) arcX2, (long) arcY2,
 729             (long) crossing->m_intersect.x, (long) crossing->m_intersect.y);
 730
 731         dc.SetPen(*wxWHITE_PEN);
 732         dc.DrawLine( (long) arcX1, (long) arcY1, (long) arcX2, (long) arcY2 );
 733
 734         node = node->GetNext();
 735     }
 736 }
 737
 738 void wxLineCrossings::ClearCrossings()
 739 {
 740     wxNode* node = m_crossings.GetFirst();
 741     while (node)
 742     {
 743         wxLineCrossing* crossing = (wxLineCrossing*) node->GetData();
 744         delete crossing;
 745         node = node->GetNext();
 746     }
 747     m_crossings.Clear();
 748 }
 749