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 license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 #ifdef __GNUG__
  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->Number();
  73     wxPoint *points = new wxPoint[n];
  74
  75     int i = 0;
  76     for ( wxNode *node = list->First(); node; node = node->Next(), i++ )
  77     {
  78         wxPoint *point = (wxPoint *)node->Data();
  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->Number();
  94     wxPoint *points = new wxPoint[n];
  95
  96     int i = 0;
  97     for ( wxNode *node = list->First(); node; node = node->Next(), i++ )
  98     {
  99         wxPoint *point = (wxPoint *)node->Data();
 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 // ----------------------------------------------------------------------------
 110 // splines
 111 // ----------------------------------------------------------------------------
 112
 113 #if wxUSE_SPLINES
 114
 115 // TODO: this API needs fixing (wxPointList, why (!const) "wxList *"?)
 116 void wxDCBase::DrawSpline(wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2, wxCoord x3, wxCoord y3)
 117 {
 118     wxList point_list;
 119
 120     wxPoint *point1 = new wxPoint;
 121     point1->x = x1; point1->y = y1;
 122     point_list.Append((wxObject*)point1);
 123
 124     wxPoint *point2 = new wxPoint;
 125     point2->x = x2; point2->y = y2;
 126     point_list.Append((wxObject*)point2);
 127
 128     wxPoint *point3 = new wxPoint;
 129     point3->x = x3; point3->y = y3;
 130     point_list.Append((wxObject*)point3);
 131
 132     DrawSpline(&point_list);
 133
 134     for( wxNode *node = point_list.First(); node; node = node->Next() )
 135     {
 136         wxPoint *p = (wxPoint *)node->Data();
 137         delete p;
 138     }
 139 }
 140
 141 void wxDCBase::DrawSpline(int n, wxPoint points[])
 142 {
 143     wxList list;
 144     for (int i =0; i < n; i++)
 145     {
 146         list.Append((wxObject*)&points[i]);
 147     }
 148
 149     DrawSpline(&list);
 150 }
 151
 152 // ----------------------------------- spline code ----------------------------------------
 153
 154 void wx_quadratic_spline(double a1, double b1, double a2, double b2,
 155                          double a3, double b3, double a4, double b4);
 156 void wx_clear_stack();
 157 int wx_spline_pop(double *x1, double *y1, double *x2, double *y2, double *x3,
 158         double *y3, double *x4, double *y4);
 159 void wx_spline_push(double x1, double y1, double x2, double y2, double x3, double y3,
 160           double x4, double y4);
 161 static bool wx_spline_add_point(double x, double y);
 162 static void wx_spline_draw_point_array(wxDCBase *dc);
 163
 164 wxList wx_spline_point_list;
 165
 166 #define                half(z1, z2)        ((z1+z2)/2.0)
 167 #define                THRESHOLD        5
 168
 169 /* iterative version */
 170
 171 void wx_quadratic_spline(double a1, double b1, double a2, double b2, double a3, double b3, double a4,
 172                  double b4)
 173 {
 174     register double  xmid, ymid;
 175     double           x1, y1, x2, y2, x3, y3, x4, y4;
 176
 177     wx_clear_stack();
 178     wx_spline_push(a1, b1, a2, b2, a3, b3, a4, b4);
 179
 180     while (wx_spline_pop(&x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4)) {
 181         xmid = (double)half(x2, x3);
 182         ymid = (double)half(y2, y3);
 183         if (fabs(x1 - xmid) < THRESHOLD && fabs(y1 - ymid) < THRESHOLD &&
 184             fabs(xmid - x4) < THRESHOLD && fabs(ymid - y4) < THRESHOLD) {
 185             wx_spline_add_point( x1, y1 );
 186             wx_spline_add_point( xmid, ymid );
 187         } else {
 188             wx_spline_push(xmid, ymid, (double)half(xmid, x3), (double)half(ymid, y3),
 189                  (double)half(x3, x4), (double)half(y3, y4), x4, y4);
 190             wx_spline_push(x1, y1, (double)half(x1, x2), (double)half(y1, y2),
 191                  (double)half(x2, xmid), (double)half(y2, ymid), xmid, ymid);
 192         }
 193     }
 194 }
 195
 196 /* utilities used by spline drawing routines */
 197
 198 typedef struct wx_spline_stack_struct {
 199     double           x1, y1, x2, y2, x3, y3, x4, y4;
 200 } Stack;
 201
 202 #define         SPLINE_STACK_DEPTH             20
 203 static Stack    wx_spline_stack[SPLINE_STACK_DEPTH];
 204 static Stack   *wx_stack_top;
 205 static int      wx_stack_count;
 206
 207 void wx_clear_stack()
 208 {
 209     wx_stack_top = wx_spline_stack;
 210     wx_stack_count = 0;
 211 }
 212
 213 void wx_spline_push(double x1, double y1, double x2, double y2, double x3, double y3, double x4, double y4)
 214 {
 215     wx_stack_top->x1 = x1;
 216     wx_stack_top->y1 = y1;
 217     wx_stack_top->x2 = x2;
 218     wx_stack_top->y2 = y2;
 219     wx_stack_top->x3 = x3;
 220     wx_stack_top->y3 = y3;
 221     wx_stack_top->x4 = x4;
 222     wx_stack_top->y4 = y4;
 223     wx_stack_top++;
 224     wx_stack_count++;
 225 }
 226
 227 int wx_spline_pop(double *x1, double *y1, double *x2, double *y2,
 228                   double *x3, double *y3, double *x4, double *y4)
 229 {
 230     if (wx_stack_count == 0)
 231         return (0);
 232     wx_stack_top--;
 233     wx_stack_count--;
 234     *x1 = wx_stack_top->x1;
 235     *y1 = wx_stack_top->y1;
 236     *x2 = wx_stack_top->x2;
 237     *y2 = wx_stack_top->y2;
 238     *x3 = wx_stack_top->x3;
 239     *y3 = wx_stack_top->y3;
 240     *x4 = wx_stack_top->x4;
 241     *y4 = wx_stack_top->y4;
 242     return (1);
 243 }
 244
 245 static bool wx_spline_add_point(double x, double y)
 246 {
 247   wxPoint *point = new wxPoint ;
 248   point->x = (int) x;
 249   point->y = (int) y;
 250   wx_spline_point_list.Append((wxObject*)point);
 251   return TRUE;
 252 }
 253
 254 static void wx_spline_draw_point_array(wxDCBase *dc)
 255 {
 256   dc->DrawLines(&wx_spline_point_list, 0, 0 );
 257   wxNode *node = wx_spline_point_list.First();
 258   while (node)
 259   {
 260     wxPoint *point = (wxPoint *)node->Data();
 261     delete point;
 262     delete node;
 263     node = wx_spline_point_list.First();
 264   }
 265 }
 266
 267 void wxDCBase::DoDrawSpline( wxList *points )
 268 {
 269     wxCHECK_RET( Ok(), wxT("invalid window dc") );
 270
 271     wxPoint *p;
 272     double           cx1, cy1, cx2, cy2, cx3, cy3, cx4, cy4;
 273     double           x1, y1, x2, y2;
 274
 275     wxNode *node = points->First();
 276     p = (wxPoint *)node->Data();
 277
 278     x1 = p->x;
 279     y1 = p->y;
 280
 281     node = node->Next();
 282     p = (wxPoint *)node->Data();
 283
 284     x2 = p->x;
 285     y2 = p->y;
 286     cx1 = (double)((x1 + x2) / 2);
 287     cy1 = (double)((y1 + y2) / 2);
 288     cx2 = (double)((cx1 + x2) / 2);
 289     cy2 = (double)((cy1 + y2) / 2);
 290
 291     wx_spline_add_point(x1, y1);
 292
 293     while ((node = node->Next()) != NULL)
 294     {
 295         p = (wxPoint *)node->Data();
 296         x1 = x2;
 297         y1 = y2;
 298         x2 = p->x;
 299         y2 = p->y;
 300         cx4 = (double)(x1 + x2) / 2;
 301         cy4 = (double)(y1 + y2) / 2;
 302         cx3 = (double)(x1 + cx4) / 2;
 303         cy3 = (double)(y1 + cy4) / 2;
 304
 305         wx_quadratic_spline(cx1, cy1, cx2, cy2, cx3, cy3, cx4, cy4);
 306
 307         cx1 = cx4;
 308         cy1 = cy4;
 309         cx2 = (double)(cx1 + x2) / 2;
 310         cy2 = (double)(cy1 + y2) / 2;
 311     }
 312
 313     wx_spline_add_point( cx1, cy1 );
 314     wx_spline_add_point( x2, y2 );
 315
 316     wx_spline_draw_point_array( this );
 317 }
 318
 319 #endif // wxUSE_SPLINES
 320
 321 // ----------------------------------------------------------------------------
 322 // enhanced text drawing
 323 // ----------------------------------------------------------------------------
 324
 325 void wxDCBase::GetMultiLineTextExtent(const wxString& text,
 326                                       wxCoord *x,
 327                                       wxCoord *y,
 328                                       wxCoord *h,
 329                                       wxFont *font)
 330 {
 331     wxCoord widthTextMax = 0, widthLine,
 332             heightTextTotal = 0, heightLineDefault = 0, heightLine = 0;
 333
 334     wxString curLine;
 335     for ( const wxChar *pc = text; ; pc++ )
 336     {
 337         if ( *pc == _T('\n') || *pc == _T('\0') )
 338         {
 339             if ( curLine.empty() )
 340             {
 341                 // we can't use GetTextExtent - it will return 0 for both width
 342                 // and height and an empty line should count in height
 343                 // calculation
 344
 345                 // assume that this line has the same height as the previous
 346                 // one
 347                 if ( !heightLineDefault )
 348                     heightLineDefault = heightLine;
 349
 350                 if ( !heightLineDefault )
 351                 {
 352                     // but we don't know it yet - choose something reasonable
 353                     GetTextExtent(_T("W"), NULL, &heightLineDefault,
 354                                   NULL, NULL, font);
 355                 }
 356
 357                 heightTextTotal += heightLineDefault;
 358             }
 359             else
 360             {
 361                 GetTextExtent(curLine, &widthLine, &heightLine,
 362                               NULL, NULL, font);
 363                 if ( widthLine > widthTextMax )
 364                     widthTextMax = widthLine;
 365                 heightTextTotal += heightLine;
 366             }
 367
 368             if ( *pc == _T('\n') )
 369             {
 370                curLine.clear();
 371             }
 372             else
 373             {
 374                // the end of string
 375                break;
 376             }
 377         }
 378         else
 379         {
 380             curLine += *pc;
 381         }
 382     }
 383
 384     if ( x )
 385         *x = widthTextMax;
 386     if ( y )
 387         *y = heightTextTotal;
 388     if ( h )
 389         *h = heightLine;
 390 }
 391
 392 void wxDCBase::DrawLabel(const wxString& text,
 393                          const wxBitmap& bitmap,
 394                          const wxRect& rect,
 395                          int alignment,
 396                          int indexAccel,
 397                          wxRect *rectBounding)
 398 {
 399     // find the text position
 400     wxCoord widthText, heightText, heightLine;
 401     GetMultiLineTextExtent(text, &widthText, &heightText, &heightLine);
 402
 403     wxCoord width, height;
 404     if ( bitmap.Ok() )
 405     {
 406         width = widthText + bitmap.GetWidth();
 407         height = bitmap.GetHeight();
 408     }
 409     else // no bitmap
 410     {
 411         width = widthText;
 412         height = heightText;
 413     }
 414
 415     wxCoord x, y;
 416     if ( alignment & wxALIGN_RIGHT )
 417     {
 418         x = rect.GetRight() - width;
 419     }
 420     else if ( alignment & wxALIGN_CENTRE_HORIZONTAL )
 421     {
 422         x = (rect.GetLeft() + rect.GetRight() + 1 - width) / 2;
 423     }
 424     else // alignment & wxALIGN_LEFT
 425     {
 426         x = rect.GetLeft();
 427     }
 428
 429     if ( alignment & wxALIGN_BOTTOM )
 430     {
 431         y = rect.GetBottom() - height;
 432     }
 433     else if ( alignment & wxALIGN_CENTRE_VERTICAL )
 434     {
 435         y = (rect.GetTop() + rect.GetBottom() + 1 - height) / 2;
 436     }
 437     else // alignment & wxALIGN_TOP
 438     {
 439         y = rect.GetTop();
 440     }
 441
 442     // draw the bitmap first
 443     wxCoord x0 = x,
 444             y0 = y,
 445             width0 = width;
 446     if ( bitmap.Ok() )
 447     {
 448         DrawBitmap(bitmap, x, y, TRUE /* use mask */);
 449
 450         wxCoord offset = bitmap.GetWidth() + 4;
 451         x += offset;
 452         width -= offset;
 453
 454         y += (height - heightText) / 2;
 455     }
 456
 457     // we will draw the underscore under the accel char later
 458     wxCoord startUnderscore = 0,
 459             endUnderscore = 0,
 460             yUnderscore = 0;
 461
 462     // split the string into lines and draw each of them separately
 463     wxString curLine;
 464     for ( const wxChar *pc = text; ; pc++ )
 465     {
 466         if ( *pc == _T('\n') || *pc == _T('\0') )
 467         {
 468             int xRealStart = x; // init it here to avoid compielr warnings
 469
 470             if ( !curLine.empty() )
 471             {
 472                 // NB: can't test for !(alignment & wxALIGN_LEFT) because
 473                 //     wxALIGN_LEFT is 0
 474                 if ( alignment & (wxALIGN_RIGHT | wxALIGN_CENTRE_HORIZONTAL) )
 475                 {
 476                     wxCoord widthLine;
 477                     GetTextExtent(curLine, &widthLine, NULL);
 478
 479                     if ( alignment & wxALIGN_RIGHT )
 480                     {
 481                         xRealStart += width - widthLine;
 482                     }
 483                     else // if ( alignment & wxALIGN_CENTRE_HORIZONTAL )
 484                     {
 485                         xRealStart += (width - widthLine) / 2;
 486                     }
 487                 }
 488                 //else: left aligned, nothing to do
 489
 490                 DrawText(curLine, xRealStart, y);
 491             }
 492
 493             y += heightLine;
 494
 495             // do we have underscore in this line? we can check yUnderscore
 496             // because it is set below to just y + heightLine if we do
 497             if ( y == yUnderscore )
 498             {
 499                 // adjust the horz positions to account for the shift
 500                 startUnderscore += xRealStart;
 501                 endUnderscore += xRealStart;
 502             }
 503
 504             if ( *pc == _T('\0') )
 505                 break;
 506
 507             curLine.clear();
 508         }
 509         else // not end of line
 510         {
 511             if ( pc - text.c_str() == indexAccel )
 512             {
 513                 // remeber to draw underscore here
 514                 GetTextExtent(curLine, &startUnderscore, NULL);
 515                 curLine += *pc;
 516                 GetTextExtent(curLine, &endUnderscore, NULL);
 517
 518                 yUnderscore = y + heightLine;
 519             }
 520             else
 521             {
 522                 curLine += *pc;
 523             }
 524         }
 525     }
 526
 527     // draw the underscore if found
 528     if ( startUnderscore != endUnderscore )
 529     {
 530         // it should be of the same colour as text
 531         SetPen(wxPen(GetTextForeground(), 0, wxSOLID));
 532
 533         yUnderscore--;
 534
 535         DrawLine(startUnderscore, yUnderscore, endUnderscore, yUnderscore);
 536     }
 537
 538     // return bounding rect if requested
 539     if ( rectBounding )
 540     {
 541         *rectBounding = wxRect(x, y - heightText, widthText, heightText);
 542     }
 543
 544     CalcBoundingBox(x0, y0);
 545     CalcBoundingBox(x0 + width0, y0 + height);
 546 }