src/common/dcbase.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        common/dcbase.cpp
   3 // Purpose:     generic methods of the wxDC Class
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     05/25/99
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) wxWindows team
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
  17     #pragma implementation "dcbase.h"
  18 #endif
  19
  20 // ----------------------------------------------------------------------------
  21 // headers
  22 // ----------------------------------------------------------------------------
  23
  24 // For compilers that support precompilation, includes "wx.h".
  25 #include "wx/wxprec.h"
  26
  27 #ifdef __BORLANDC__
  28     #pragma hdrstop
  29 #endif
  30
  31 #include "wx/dc.h"
  32
  33 #include <math.h>
  34
  35 // bool wxDCBase::sm_cacheing = FALSE;
  36
  37 // ============================================================================
  38 // implementation
  39 // ============================================================================
  40
  41 // ----------------------------------------------------------------------------
  42 // special symbols
  43 // ----------------------------------------------------------------------------
  44
  45 void wxDCBase::DoDrawCheckMark(wxCoord x1, wxCoord y1,
  46                                wxCoord width, wxCoord height)
  47 {
  48     wxCHECK_RET( Ok(), wxT("invalid window dc") );
  49
  50     wxCoord x2 = x1 + width,
  51             y2 = y1 + height;
  52
  53     // this is to yield width of 3 for width == height == 10
  54     SetPen(wxPen(GetTextForeground(), (width + height + 1) / 7, wxSOLID));
  55
  56     // we're drawing a scaled version of wx/generic/tick.xpm here
  57     wxCoord x3 = x1 + (4*width) / 10,   // x of the tick bottom
  58             y3 = y1 + height / 2;       // y of the left tick branch
  59     DoDrawLine(x1, y3, x3, y2);
  60     DoDrawLine(x3, y2, x2, y1);
  61
  62     CalcBoundingBox(x1, y1);
  63     CalcBoundingBox(x2, y2);
  64 }
  65
  66 // ----------------------------------------------------------------------------
  67 // line/polygons
  68 // ----------------------------------------------------------------------------
  69
  70 void wxDCBase::DrawLines(const wxList *list, wxCoord xoffset, wxCoord yoffset)
  71 {
  72     int n = list->GetCount();
  73     wxPoint *points = new wxPoint[n];
  74
  75     int i = 0;
  76     for ( wxList::compatibility_iterator node = list->GetFirst(); node; node = node->GetNext(), i++ )
  77     {
  78         wxPoint *point = (wxPoint *)node->GetData();
  79         points[i].x = point->x;
  80         points[i].y = point->y;
  81     }
  82
  83     DoDrawLines(n, points, xoffset, yoffset);
  84
  85     delete [] points;
  86 }
  87
  88
  89 void wxDCBase::DrawPolygon(const wxList *list,
  90                            wxCoord xoffset, wxCoord yoffset,
  91                            int fillStyle)
  92 {
  93     int n = list->GetCount();
  94     wxPoint *points = new wxPoint[n];
  95
  96     int i = 0;
  97     for ( wxList::compatibility_iterator node = list->GetFirst(); node; node = node->GetNext(), i++ )
  98     {
  99         wxPoint *point = (wxPoint *)node->GetData();
 100         points[i].x = point->x;
 101         points[i].y = point->y;
 102     }
 103
 104     DoDrawPolygon(n, points, xoffset, yoffset, fillStyle);
 105
 106     delete [] points;
 107 }
 108
 109 void
 110 wxDCBase::DoDrawPolyPolygon(int n,
 111                             int start[],
 112                             wxPoint points[],
 113                             wxCoord xoffset, wxCoord yoffset,
 114                             int fillStyle)
 115 {
 116     if ( n == 1 )
 117     {
 118         DoDrawPolygon(start[0], points, xoffset, yoffset, fillStyle);
 119         return;
 120     }
 121
 122     int      i, j, lastOfs;
 123     wxPoint* pts;
 124     wxPen    pen;
 125
 126     for (i = j = lastOfs = 0; i < n; i++)
 127     {
 128         lastOfs = j;
 129         j      += start[i];
 130     }
 131     pts = new wxPoint[j+n-1];
 132     for (i = 0; i < j; i++)
 133         pts[i] = points[i];
 134     for (i = 2; i <= n; i++)
 135     {
 136         lastOfs -= start[n-i];
 137         pts[j++] = pts[lastOfs];
 138     }
 139
 140     pen = GetPen();
 141     SetPen(wxPen(*wxBLACK, 0, wxTRANSPARENT));
 142     DoDrawPolygon(j, pts, xoffset, yoffset, fillStyle);
 143     SetPen(pen);
 144     for (i = j = 0; i < n; i++)
 145     {
 146         DoDrawLines(start[i], pts+j, xoffset, yoffset);
 147         j += start[i];
 148     }
 149     delete pts;
 150 }
 151
 152 // ----------------------------------------------------------------------------
 153 // splines
 154 // ----------------------------------------------------------------------------
 155
 156 #if wxUSE_SPLINES
 157
 158 // TODO: this API needs fixing (wxPointList, why (!const) "wxList *"?)
 159 void wxDCBase::DrawSpline(wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2, wxCoord x3, wxCoord y3)
 160 {
 161     wxList point_list;
 162
 163     wxPoint *point1 = new wxPoint;
 164     point1->x = x1; point1->y = y1;
 165     point_list.Append((wxObject*)point1);
 166
 167     wxPoint *point2 = new wxPoint;
 168     point2->x = x2; point2->y = y2;
 169     point_list.Append((wxObject*)point2);
 170
 171     wxPoint *point3 = new wxPoint;
 172     point3->x = x3; point3->y = y3;
 173     point_list.Append((wxObject*)point3);
 174
 175     DrawSpline(&point_list);
 176
 177     for( wxList::compatibility_iterator node = point_list.GetFirst(); node; node = node->GetNext() )
 178     {
 179         wxPoint *p = (wxPoint *)node->GetData();
 180         delete p;
 181     }
 182 }
 183
 184 void wxDCBase::DrawSpline(int n, wxPoint points[])
 185 {
 186     wxList list;
 187     for (int i =0; i < n; i++)
 188     {
 189         list.Append((wxObject*)&points[i]);
 190     }
 191
 192     DrawSpline(&list);
 193 }
 194
 195 // ----------------------------------- spline code ----------------------------------------
 196
 197 void wx_quadratic_spline(double a1, double b1, double a2, double b2,
 198                          double a3, double b3, double a4, double b4);
 199 void wx_clear_stack();
 200 int wx_spline_pop(double *x1, double *y1, double *x2, double *y2, double *x3,
 201         double *y3, double *x4, double *y4);
 202 void wx_spline_push(double x1, double y1, double x2, double y2, double x3, double y3,
 203           double x4, double y4);
 204 static bool wx_spline_add_point(double x, double y);
 205 static void wx_spline_draw_point_array(wxDCBase *dc);
 206
 207 wxList wx_spline_point_list;
 208
 209 #define                half(z1, z2)        ((z1+z2)/2.0)
 210 #define                THRESHOLD        5
 211
 212 /* iterative version */
 213
 214 void wx_quadratic_spline(double a1, double b1, double a2, double b2, double a3, double b3, double a4,
 215                  double b4)
 216 {
 217     register double  xmid, ymid;
 218     double           x1, y1, x2, y2, x3, y3, x4, y4;
 219
 220     wx_clear_stack();
 221     wx_spline_push(a1, b1, a2, b2, a3, b3, a4, b4);
 222
 223     while (wx_spline_pop(&x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4)) {
 224         xmid = (double)half(x2, x3);
 225         ymid = (double)half(y2, y3);
 226         if (fabs(x1 - xmid) < THRESHOLD && fabs(y1 - ymid) < THRESHOLD &&
 227             fabs(xmid - x4) < THRESHOLD && fabs(ymid - y4) < THRESHOLD) {
 228             wx_spline_add_point( x1, y1 );
 229             wx_spline_add_point( xmid, ymid );
 230         } else {
 231             wx_spline_push(xmid, ymid, (double)half(xmid, x3), (double)half(ymid, y3),
 232                  (double)half(x3, x4), (double)half(y3, y4), x4, y4);
 233             wx_spline_push(x1, y1, (double)half(x1, x2), (double)half(y1, y2),
 234                  (double)half(x2, xmid), (double)half(y2, ymid), xmid, ymid);
 235         }
 236     }
 237 }
 238
 239 /* utilities used by spline drawing routines */
 240
 241 typedef struct wx_spline_stack_struct {
 242     double           x1, y1, x2, y2, x3, y3, x4, y4;
 243 } Stack;
 244
 245 #define         SPLINE_STACK_DEPTH             20
 246 static Stack    wx_spline_stack[SPLINE_STACK_DEPTH];
 247 static Stack   *wx_stack_top;
 248 static int      wx_stack_count;
 249
 250 void wx_clear_stack()
 251 {
 252     wx_stack_top = wx_spline_stack;
 253     wx_stack_count = 0;
 254 }
 255
 256 void wx_spline_push(double x1, double y1, double x2, double y2, double x3, double y3, double x4, double y4)
 257 {
 258     wx_stack_top->x1 = x1;
 259     wx_stack_top->y1 = y1;
 260     wx_stack_top->x2 = x2;
 261     wx_stack_top->y2 = y2;
 262     wx_stack_top->x3 = x3;
 263     wx_stack_top->y3 = y3;
 264     wx_stack_top->x4 = x4;
 265     wx_stack_top->y4 = y4;
 266     wx_stack_top++;
 267     wx_stack_count++;
 268 }
 269
 270 int wx_spline_pop(double *x1, double *y1, double *x2, double *y2,
 271                   double *x3, double *y3, double *x4, double *y4)
 272 {
 273     if (wx_stack_count == 0)
 274         return (0);
 275     wx_stack_top--;
 276     wx_stack_count--;
 277     *x1 = wx_stack_top->x1;
 278     *y1 = wx_stack_top->y1;
 279     *x2 = wx_stack_top->x2;
 280     *y2 = wx_stack_top->y2;
 281     *x3 = wx_stack_top->x3;
 282     *y3 = wx_stack_top->y3;
 283     *x4 = wx_stack_top->x4;
 284     *y4 = wx_stack_top->y4;
 285     return (1);
 286 }
 287
 288 static bool wx_spline_add_point(double x, double y)
 289 {
 290   wxPoint *point = new wxPoint ;
 291   point->x = (int) x;
 292   point->y = (int) y;
 293   wx_spline_point_list.Append((wxObject*)point);
 294   return TRUE;
 295 }
 296
 297 static void wx_spline_draw_point_array(wxDCBase *dc)
 298 {
 299   dc->DrawLines(&wx_spline_point_list, 0, 0 );
 300   wxList::compatibility_iterator node = wx_spline_point_list.GetFirst();
 301   while (node)
 302   {
 303     wxPoint *point = (wxPoint *)node->GetData();
 304     delete point;
 305     wx_spline_point_list.Erase(node);
 306     node = wx_spline_point_list.GetFirst();
 307   }
 308 }
 309
 310 void wxDCBase::DoDrawSpline( wxList *points )
 311 {
 312     wxCHECK_RET( Ok(), wxT("invalid window dc") );
 313
 314     wxPoint *p;
 315     double           cx1, cy1, cx2, cy2, cx3, cy3, cx4, cy4;
 316     double           x1, y1, x2, y2;
 317
 318     wxList::compatibility_iterator node = points->GetFirst();
 319     p = (wxPoint *)node->GetData();
 320
 321     x1 = p->x;
 322     y1 = p->y;
 323
 324     node = node->GetNext();
 325     p = (wxPoint *)node->GetData();
 326
 327     x2 = p->x;
 328     y2 = p->y;
 329     cx1 = (double)((x1 + x2) / 2);
 330     cy1 = (double)((y1 + y2) / 2);
 331     cx2 = (double)((cx1 + x2) / 2);
 332     cy2 = (double)((cy1 + y2) / 2);
 333
 334     wx_spline_add_point(x1, y1);
 335
 336     while ((node = node->GetNext())
 337 #if !wxUSE_STL
 338            != NULL
 339 #endif // !wxUSE_STL
 340           )
 341     {
 342         p = (wxPoint *)node->GetData();
 343         x1 = x2;
 344         y1 = y2;
 345         x2 = p->x;
 346         y2 = p->y;
 347         cx4 = (double)(x1 + x2) / 2;
 348         cy4 = (double)(y1 + y2) / 2;
 349         cx3 = (double)(x1 + cx4) / 2;
 350         cy3 = (double)(y1 + cy4) / 2;
 351
 352         wx_quadratic_spline(cx1, cy1, cx2, cy2, cx3, cy3, cx4, cy4);
 353
 354         cx1 = cx4;
 355         cy1 = cy4;
 356         cx2 = (double)(cx1 + x2) / 2;
 357         cy2 = (double)(cy1 + y2) / 2;
 358     }
 359
 360     wx_spline_add_point( cx1, cy1 );
 361     wx_spline_add_point( x2, y2 );
 362
 363     wx_spline_draw_point_array( this );
 364 }
 365
 366 #endif // wxUSE_SPLINES
 367
 368 // ----------------------------------------------------------------------------
 369 // Partial Text Extents
 370 // ----------------------------------------------------------------------------
 371
 372
 373 // Each element of the array will be the width of the string up to and
 374 // including the coresoponding character in text.  This is the generic
 375 // implementation, the port-specific classes should do this with native APIs
 376 // if available.
 377
 378 bool wxDCBase::DoGetPartialTextExtents(const wxString& text, wxArrayInt& widths) const
 379 {
 380     int totalWidth = 0;
 381     size_t i;
 382
 383     widths.Empty();
 384     widths.Add(0, text.Length());
 385
 386     // Calculate the position of each character based on the widths of
 387     // the previous characters
 388     for (i=0; i<text.Length(); i++) {
 389         int w, h;
 390         GetTextExtent(text[i], &w, &h);
 391         totalWidth += w;
 392         widths[i] = totalWidth;
 393     }
 394     return true;
 395 }
 396
 397
 398 // ----------------------------------------------------------------------------
 399 // enhanced text drawing
 400 // ----------------------------------------------------------------------------
 401
 402 void wxDCBase::GetMultiLineTextExtent(const wxString& text,
 403                                       wxCoord *x,
 404                                       wxCoord *y,
 405                                       wxCoord *h,
 406                                       wxFont *font)
 407 {
 408     wxCoord widthTextMax = 0, widthLine,
 409             heightTextTotal = 0, heightLineDefault = 0, heightLine = 0;
 410
 411     wxString curLine;
 412     for ( const wxChar *pc = text; ; pc++ )
 413     {
 414         if ( *pc == _T('\n') || *pc == _T('\0') )
 415         {
 416             if ( curLine.empty() )
 417             {
 418                 // we can't use GetTextExtent - it will return 0 for both width
 419                 // and height and an empty line should count in height
 420                 // calculation
 421
 422                 // assume that this line has the same height as the previous
 423                 // one
 424                 if ( !heightLineDefault )
 425                     heightLineDefault = heightLine;
 426
 427                 if ( !heightLineDefault )
 428                 {
 429                     // but we don't know it yet - choose something reasonable
 430                     GetTextExtent(_T("W"), NULL, &heightLineDefault,
 431                                   NULL, NULL, font);
 432                 }
 433
 434                 heightTextTotal += heightLineDefault;
 435             }
 436             else
 437             {
 438                 GetTextExtent(curLine, &widthLine, &heightLine,
 439                               NULL, NULL, font);
 440                 if ( widthLine > widthTextMax )
 441                     widthTextMax = widthLine;
 442                 heightTextTotal += heightLine;
 443             }
 444
 445             if ( *pc == _T('\n') )
 446             {
 447                curLine.clear();
 448             }
 449             else
 450             {
 451                // the end of string
 452                break;
 453             }
 454         }
 455         else
 456         {
 457             curLine += *pc;
 458         }
 459     }
 460
 461     if ( x )
 462         *x = widthTextMax;
 463     if ( y )
 464         *y = heightTextTotal;
 465     if ( h )
 466         *h = heightLine;
 467 }
 468
 469 void wxDCBase::DrawLabel(const wxString& text,
 470                          const wxBitmap& bitmap,
 471                          const wxRect& rect,
 472                          int alignment,
 473                          int indexAccel,
 474                          wxRect *rectBounding)
 475 {
 476     // find the text position
 477     wxCoord widthText, heightText, heightLine;
 478     GetMultiLineTextExtent(text, &widthText, &heightText, &heightLine);
 479
 480     wxCoord width, height;
 481     if ( bitmap.Ok() )
 482     {
 483         width = widthText + bitmap.GetWidth();
 484         height = bitmap.GetHeight();
 485     }
 486     else // no bitmap
 487     {
 488         width = widthText;
 489         height = heightText;
 490     }
 491
 492     wxCoord x, y;
 493     if ( alignment & wxALIGN_RIGHT )
 494     {
 495         x = rect.GetRight() - width;
 496     }
 497     else if ( alignment & wxALIGN_CENTRE_HORIZONTAL )
 498     {
 499         x = (rect.GetLeft() + rect.GetRight() + 1 - width) / 2;
 500     }
 501     else // alignment & wxALIGN_LEFT
 502     {
 503         x = rect.GetLeft();
 504     }
 505
 506     if ( alignment & wxALIGN_BOTTOM )
 507     {
 508         y = rect.GetBottom() - height;
 509     }
 510     else if ( alignment & wxALIGN_CENTRE_VERTICAL )
 511     {
 512         y = (rect.GetTop() + rect.GetBottom() + 1 - height) / 2;
 513     }
 514     else // alignment & wxALIGN_TOP
 515     {
 516         y = rect.GetTop();
 517     }
 518
 519     // draw the bitmap first
 520     wxCoord x0 = x,
 521             y0 = y,
 522             width0 = width;
 523     if ( bitmap.Ok() )
 524     {
 525         DrawBitmap(bitmap, x, y, TRUE /* use mask */);
 526
 527         wxCoord offset = bitmap.GetWidth() + 4;
 528         x += offset;
 529         width -= offset;
 530
 531         y += (height - heightText) / 2;
 532     }
 533
 534     // we will draw the underscore under the accel char later
 535     wxCoord startUnderscore = 0,
 536             endUnderscore = 0,
 537             yUnderscore = 0;
 538
 539     // split the string into lines and draw each of them separately
 540     wxString curLine;
 541     for ( const wxChar *pc = text; ; pc++ )
 542     {
 543         if ( *pc == _T('\n') || *pc == _T('\0') )
 544         {
 545             int xRealStart = x; // init it here to avoid compielr warnings
 546
 547             if ( !curLine.empty() )
 548             {
 549                 // NB: can't test for !(alignment & wxALIGN_LEFT) because
 550                 //     wxALIGN_LEFT is 0
 551                 if ( alignment & (wxALIGN_RIGHT | wxALIGN_CENTRE_HORIZONTAL) )
 552                 {
 553                     wxCoord widthLine;
 554                     GetTextExtent(curLine, &widthLine, NULL);
 555
 556                     if ( alignment & wxALIGN_RIGHT )
 557                     {
 558                         xRealStart += width - widthLine;
 559                     }
 560                     else // if ( alignment & wxALIGN_CENTRE_HORIZONTAL )
 561                     {
 562                         xRealStart += (width - widthLine) / 2;
 563                     }
 564                 }
 565                 //else: left aligned, nothing to do
 566
 567                 DrawText(curLine, xRealStart, y);
 568             }
 569
 570             y += heightLine;
 571
 572             // do we have underscore in this line? we can check yUnderscore
 573             // because it is set below to just y + heightLine if we do
 574             if ( y == yUnderscore )
 575             {
 576                 // adjust the horz positions to account for the shift
 577                 startUnderscore += xRealStart;
 578                 endUnderscore += xRealStart;
 579             }
 580
 581             if ( *pc == _T('\0') )
 582                 break;
 583
 584             curLine.clear();
 585         }
 586         else // not end of line
 587         {
 588             if ( pc - text.c_str() == indexAccel )
 589             {
 590                 // remeber to draw underscore here
 591                 GetTextExtent(curLine, &startUnderscore, NULL);
 592                 curLine += *pc;
 593                 GetTextExtent(curLine, &endUnderscore, NULL);
 594
 595                 yUnderscore = y + heightLine;
 596             }
 597             else
 598             {
 599                 curLine += *pc;
 600             }
 601         }
 602     }
 603
 604     // draw the underscore if found
 605     if ( startUnderscore != endUnderscore )
 606     {
 607         // it should be of the same colour as text
 608         SetPen(wxPen(GetTextForeground(), 0, wxSOLID));
 609
 610         yUnderscore--;
 611
 612         DrawLine(startUnderscore, yUnderscore, endUnderscore, yUnderscore);
 613     }
 614
 615     // return bounding rect if requested
 616     if ( rectBounding )
 617     {
 618         *rectBounding = wxRect(x, y - heightText, widthText, heightText);
 619     }
 620
 621     CalcBoundingBox(x0, y0);
 622     CalcBoundingBox(x0 + width0, y0 + height);
 623 }
 624
 625 /*
 626 Notes for wxWindows DrawEllipticArcRot(...)
 627
 628 wxDCBase::DrawEllipticArcRot(...) draws a rotated elliptic arc or an ellipse.
 629 It uses wxDCBase::CalculateEllipticPoints(...) and wxDCBase::Rotate(...),
 630 which are also new.
 631
 632 All methods are generic, so they can be implemented in wxDCBase.
 633 DoDrawEllipticArcRot(...) is virtual, so it can be called from deeper
 634 methods like (WinCE) wxDC::DoDrawArc(...).
 635
 636 CalculateEllipticPoints(...) fills a given list of wxPoints with some points
 637 of an elliptic arc. The algorithm is pixel-based: In every row (in flat
 638 parts) or every column (in steep parts) only one pixel is calculated.
 639 Trigonometric calculation (sin, cos, tan, atan) is only done if the
 640 starting angle is not equal to the ending angle. The calculation of the
 641 pixels is done using simple arithmetic only and should perform not too
 642 bad even on devices without floating point processor. I didn't test this yet.
 643
 644 Rotate(...) rotates a list of point pixel-based, you will see rounding errors.
 645 For instance: an ellipse rotated 180 degrees is drawn
 646 slightly different from the original.
 647
 648 The points are then moved to an array and used to draw a polyline and/or polygon
 649 (with center added, the pie).
 650 The result looks quite similar to the native ellipse, only e few pixels differ.
 651
 652 The performance on a desktop system (Athlon 1800, WinXP) is about 7 times
 653 slower as DrawEllipse(...), which calls the native API.
 654 An rotated ellipse outside the clipping region takes nearly the same time,
 655 while an native ellipse outside takes nearly no time to draw.
 656
 657 If you draw an arc with this new method, you will see the starting and ending angles
 658 are calculated properly.
 659 If you use DrawEllipticArc(...), you will see they are only correct for circles
 660 and not properly calculated for ellipses.
 661
 662 Peter Lenhard
 663 p.lenhard@t-online.de
 664 */
 665
 666 #ifdef __WXWINCE__
 667 void wxDCBase::DoDrawEllipticArcRot( wxCoord x, wxCoord y,
 668                                      wxCoord w, wxCoord h,
 669                                      double sa, double ea, double angle )
 670 {
 671     wxList list;
 672
 673     CalculateEllipticPoints( &list, x, y, w, h, sa, ea );
 674     Rotate( &list, angle, wxPoint( x+w/2, y+h/2 ) );
 675
 676     // Add center (for polygon/pie)
 677     list.Append( (wxObject*) new wxPoint( x+w/2, y+h/2 ) );
 678
 679     // copy list into array and delete list elements
 680     int n = list.Number();
 681     wxPoint *points = new wxPoint[n];
 682     int i = 0;
 683     wxNode* node = 0;
 684     for ( node = list.First(); node; node = node->Next(), i++ )
 685     {
 686         wxPoint *point = (wxPoint *)node->Data();
 687         points[i].x = point->x;
 688         points[i].y = point->y;
 689         delete point;
 690     }
 691
 692     // first draw the pie without pen, if necessary
 693     if( GetBrush() != *wxTRANSPARENT_BRUSH )
 694     {
 695         wxPen tempPen( GetPen() );
 696         SetPen( *wxTRANSPARENT_PEN );
 697         DoDrawPolygon( n, points, 0, 0 );
 698         SetPen( tempPen );
 699     }
 700
 701     // then draw the arc without brush, if necessary
 702     if( GetPen() != *wxTRANSPARENT_PEN )
 703     {
 704         // without center
 705         DoDrawLines( n-1, points, 0, 0 );
 706     }
 707
 708     delete [] points;
 709
 710 } // DrawEllipticArcRot
 711
 712 void wxDCBase::Rotate( wxList* points, double angle, wxPoint center )
 713 {
 714     if( angle != 0.0 )
 715     {
 716         double pi(3.1415926536);
 717         double dSinA = -sin(angle*2.0*pi/360.0);
 718         double dCosA = cos(angle*2.0*pi/360.0);
 719         for ( wxNode* node = points->First(); node; node = node->Next() )
 720         {
 721             wxPoint* point = (wxPoint*)node->Data();
 722
 723             // transform coordinates, if necessary
 724             if( center.x ) point->x -= center.x;
 725             if( center.y ) point->y -= center.y;
 726
 727             // calculate rotation, rounding simply by implicit cast to integer
 728             int xTemp = point->x * dCosA - point->y * dSinA;
 729             point->y = point->x * dSinA + point->y * dCosA;
 730             point->x = xTemp;
 731
 732             // back transform coordinates, if necessary
 733             if( center.x ) point->x += center.x;
 734             if( center.y ) point->y += center.y;
 735         }
 736     }
 737 }
 738
 739 void wxDCBase::CalculateEllipticPoints( wxList* points,
 740                                         wxCoord xStart, wxCoord yStart,
 741                                         wxCoord w, wxCoord h,
 742                                         double sa, double ea )
 743 {
 744     double pi = 3.1415926535;
 745     double sar = 0;
 746     double ear = 0;
 747     int xsa = 0;
 748     int ysa = 0;
 749     int xea = 0;
 750     int yea = 0;
 751     int sq = 0;
 752     int eq = 0;
 753     bool bUseAngles = false;
 754     if( w<0 ) w = -w;
 755     if( h<0 ) h = -h;
 756     // half-axes
 757     wxCoord a = w/2;
 758     wxCoord b = h/2;
 759     // decrement 1 pixel if ellipse is smaller than 2*a, 2*b
 760     int decrX = 0;
 761     if( 2*a == w ) decrX = 1;
 762     int decrY = 0;
 763     if( 2*b == h ) decrY = 1;
 764     // center
 765     wxCoord xCenter = xStart + a;
 766     wxCoord yCenter = yStart + b;
 767     // calculate data for start and end, if necessary
 768     if( sa != ea )
 769     {
 770         bUseAngles = true;
 771         // normalisation of angles
 772         while( sa<0 ) sa += 360;
 773         while( ea<0 ) ea += 360;
 774         while( sa>=360 ) sa -= 360;
 775         while( ea>=360 ) ea -= 360;
 776         // calculate quadrant numbers
 777         if( sa > 270 ) sq = 3;
 778         else if( sa > 180 ) sq = 2;
 779         else if( sa > 90 ) sq = 1;
 780         if( ea > 270 ) eq = 3;
 781         else if( ea > 180 ) eq = 2;
 782         else if( ea > 90 ) eq = 1;
 783         sar = sa * pi / 180.0;
 784         ear = ea * pi / 180.0;
 785         // correct angle circle -> ellipse
 786         sar = atan( -a/(double)b * tan( sar ) );
 787         if ( sq == 1 || sq == 2 ) sar += pi;
 788         ear = atan( -a/(double)b * tan( ear ) );
 789         if ( eq == 1 || eq == 2 ) ear += pi;
 790         // coordinates of points
 791         xsa = xCenter + a * cos( sar );
 792         if( sq == 0 || sq == 3 ) xsa -= decrX;
 793         ysa = yCenter + b * sin( sar );
 794         if( sq == 2 || sq == 3 ) ysa -= decrY;
 795         xea = xCenter + a * cos( ear );
 796         if( eq == 0 || eq == 3 ) xea -= decrX;
 797         yea = yCenter + b * sin( ear );
 798         if( eq == 2 || eq == 3 ) yea -= decrY;
 799     } // if iUseAngles
 800     // calculate c1 = b^2, c2 = b^2/a^2 with a = w/2, b = h/2
 801     double c1 = b * b;
 802     double c2 = 2.0 / w;
 803     c2 *= c2;
 804     c2 *= c1;
 805     wxCoord x = 0;
 806     wxCoord y = b;
 807     long x2 = 1;
 808     long y2 = y*y;
 809     long y2_old = 0;
 810     long y_old = 0;
 811     // Lists for quadrant 1 to 4
 812     wxList pointsarray[4];
 813     // Calculate points for first quadrant and set in all quadrants
 814     for( x = 0; x <= a; ++x )
 815     {
 816         x2 = x2+x+x-1;
 817         y2_old = y2;
 818         y_old = y;
 819         bool bNewPoint = false;
 820         while( y2 > c1 - c2 * x2 && y > 0 )
 821         {
 822             bNewPoint = true;
 823             y2 = y2-y-y+1;
 824             --y;
 825         }
 826         // old y now to big: set point with old y, old x
 827         if( bNewPoint && x>1)
 828         {
 829             int x1 = x - 1;
 830             // remove points on the same line
 831             pointsarray[0].Insert( (wxObject*) new wxPoint( xCenter + x1 - decrX, yCenter - y_old ) );
 832             pointsarray[1].Append( (wxObject*) new wxPoint( xCenter - x1, yCenter - y_old ) );
 833             pointsarray[2].Insert( (wxObject*) new wxPoint( xCenter - x1, yCenter + y_old - decrY ) );
 834             pointsarray[3].Append( (wxObject*) new wxPoint( xCenter + x1 - decrX, yCenter + y_old - decrY ) );
 835         } // set point
 836     } // calculate point
 837
 838     // Starting and/or ending points for the quadrants, first quadrant gets both.
 839     pointsarray[0].Insert( (wxObject*) new wxPoint( xCenter + a - decrX, yCenter ) );
 840     pointsarray[0].Append( (wxObject*) new wxPoint( xCenter, yCenter - b ) );
 841     pointsarray[1].Append( (wxObject*) new wxPoint( xCenter - a, yCenter ) );
 842     pointsarray[2].Append( (wxObject*) new wxPoint( xCenter, yCenter + b - decrY ) );
 843     pointsarray[3].Append( (wxObject*) new wxPoint( xCenter + a - decrX, yCenter ) );
 844
 845     // copy quadrants in original list
 846     if( bUseAngles )
 847     {
 848         // Copy the right part of the points in the lists
 849         // and delete the wxPoints, because they do not leave this method.
 850         points->Append( (wxObject*) new wxPoint( xsa, ysa ) );
 851         int q = sq;
 852         bool bStarted = false;
 853         bool bReady = false;
 854         bool bForceTurn = ( sq == eq && sa > ea );
 855         while( !bReady )
 856         {
 857             for( wxNode *node = pointsarray[q].First(); node; node = node->Next() )
 858             {
 859                 // once: go to starting point in start quadrant
 860                 if( !bStarted &&
 861                     (
 862                       ( (wxPoint*) node->Data() )->x < xsa+1 && q <= 1
 863                       ||
 864                       ( (wxPoint*) node->Data() )->x > xsa-1 && q >= 2
 865                     )
 866                   )
 867                 {
 868                     bStarted = true;
 869                 }
 870
 871                 // copy point, if not at ending point
 872                 if( bStarted )
 873                 {
 874                     if( q != eq || bForceTurn
 875                         ||
 876                         ( (wxPoint*) node->Data() )->x > xea+1 && q <= 1
 877                         ||
 878                         ( (wxPoint*) node->Data() )->x < xea-1 && q >= 2
 879                       )
 880                     {
 881                         // copy point
 882                         wxPoint* pPoint = new wxPoint( *((wxPoint*) node->Data() ) );
 883                         points->Append( (wxObject*) pPoint );
 884                     }
 885                     else if( q == eq && !bForceTurn || ( (wxPoint*) node->Data() )->x == xea)
 886                     {
 887                         bReady = true;
 888                     }
 889                 }
 890             } // for node
 891             ++q;
 892             if( q > 3 ) q = 0;
 893             bForceTurn = false;
 894             bStarted = true;
 895         } // while not bReady
 896         points->Append( (wxObject*) new wxPoint( xea, yea ) );
 897
 898         // delete points
 899         for( q = 0; q < 4; ++q )
 900         {
 901             for( wxNode *node = pointsarray[q].First(); node; node = node->Next() )
 902             {
 903                 wxPoint *p = (wxPoint *)node->Data();
 904                 delete p;
 905             }
 906         }
 907
 908     }
 909     else
 910     {
 911         // copy whole ellipse, wxPoints will be deleted outside
 912         for( wxNode *node = pointsarray[0].First(); node; node = node->Next() )
 913         {
 914             wxObject *p = node->Data();
 915             points->Append( p );
 916         }
 917         for( node = pointsarray[1].First(); node; node = node->Next() )
 918         {
 919             wxObject *p = node->Data();
 920             points->Append( p );
 921         }
 922         for( node = pointsarray[2].First(); node; node = node->Next() )
 923         {
 924             wxObject *p = node->Data();
 925             points->Append( p );
 926         }
 927         for( node = pointsarray[3].First(); node; node = node->Next() )
 928         {
 929             wxObject *p = node->Data();
 930             points->Append( p );
 931         }
 932     } // not iUseAngles
 933 } // CalculateEllipticPoints
 934
 935 #endif
 936