src/common/dcbase.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        dc.cpp
   3 // Purpose:     wxDC Class
   4 // Author:      Brian Macy
   5 // Modified by:
   6 // Created:     05/25/99
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) wxWindows team
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifdef __GNUG__
  13 #pragma implementation "dcbase.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 #include "wx/dc.h"
  24
  25 #include <math.h>
  26
  27 void wxDCBase::DoDrawCheckMark(wxCoord x1, wxCoord y1,
  28                                wxCoord width, wxCoord height)
  29 {
  30     wxCHECK_RET( Ok(), wxT("invalid window dc") );
  31
  32     wxCoord x2 = x1 + width,
  33             y2 = y1 + height;
  34
  35     // this is to yield width of 3 for width == height == 10
  36     SetPen(wxPen(GetTextForeground(), (width + height + 1) / 7, wxSOLID));
  37
  38     // we're drawing a scaled version of wx/generic/tick.xpm here
  39     wxCoord x3 = x1 + (4*width) / 10,   // x of the tick bottom
  40             y3 = y1 + height / 2;       // y of the left tick branch
  41     DoDrawLine(x1, y3, x3, y2);
  42     DoDrawLine(x3, y2, x2, y1);
  43
  44     CalcBoundingBox(x1, y1);
  45     CalcBoundingBox(x2, y2);
  46 }
  47
  48 void wxDCBase::DrawLines(const wxList *list, wxCoord xoffset, wxCoord yoffset)
  49 {
  50     int n = list->Number();
  51     wxPoint *points = new wxPoint[n];
  52
  53     int i = 0;
  54     for ( wxNode *node = list->First(); node; node = node->Next(), i++ )
  55     {
  56         wxPoint *point = (wxPoint *)node->Data();
  57         points[i].x = point->x;
  58         points[i].y = point->y;
  59     }
  60
  61     DoDrawLines(n, points, xoffset, yoffset);
  62
  63     delete [] points;
  64 }
  65
  66
  67 void wxDCBase::DrawPolygon(const wxList *list,
  68                            wxCoord xoffset, wxCoord yoffset,
  69                            int fillStyle)
  70 {
  71     int n = list->Number();
  72     wxPoint *points = new wxPoint[n];
  73
  74     int i = 0;
  75     for ( wxNode *node = list->First(); node; node = node->Next(), i++ )
  76     {
  77         wxPoint *point = (wxPoint *)node->Data();
  78         points[i].x = point->x;
  79         points[i].y = point->y;
  80     }
  81
  82     DoDrawPolygon(n, points, xoffset, yoffset, fillStyle);
  83
  84     delete [] points;
  85 }
  86
  87
  88 #if wxUSE_SPLINES
  89
  90 // TODO: this API needs fixing (wxPointList, why (!const) "wxList *"?)
  91 void wxDCBase::DrawSpline(wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2, wxCoord x3, wxCoord y3)
  92 {
  93     wxList point_list;
  94
  95     wxPoint *point1 = new wxPoint;
  96     point1->x = x1; point1->y = y1;
  97     point_list.Append((wxObject*)point1);
  98
  99     wxPoint *point2 = new wxPoint;
 100     point2->x = x2; point2->y = y2;
 101     point_list.Append((wxObject*)point2);
 102
 103     wxPoint *point3 = new wxPoint;
 104     point3->x = x3; point3->y = y3;
 105     point_list.Append((wxObject*)point3);
 106
 107     DrawSpline(&point_list);
 108
 109     for( wxNode *node = point_list.First(); node; node = node->Next() )
 110     {
 111         wxPoint *p = (wxPoint *)node->Data();
 112         delete p;
 113     }
 114 }
 115
 116 void wxDCBase::DrawSpline(int n, wxPoint points[])
 117 {
 118     wxList list;
 119     for (int i =0; i < n; i++)
 120     {
 121         list.Append((wxObject*)&points[i]);
 122     }
 123
 124     DrawSpline(&list);
 125 }
 126
 127 // ----------------------------------- spline code ----------------------------------------
 128
 129 void wx_quadratic_spline(double a1, double b1, double a2, double b2,
 130                          double a3, double b3, double a4, double b4);
 131 void wx_clear_stack();
 132 int wx_spline_pop(double *x1, double *y1, double *x2, double *y2, double *x3,
 133         double *y3, double *x4, double *y4);
 134 void wx_spline_push(double x1, double y1, double x2, double y2, double x3, double y3,
 135           double x4, double y4);
 136 static bool wx_spline_add_point(double x, double y);
 137 static void wx_spline_draw_point_array(wxDCBase *dc);
 138
 139 wxList wx_spline_point_list;
 140
 141 #define                half(z1, z2)        ((z1+z2)/2.0)
 142 #define                THRESHOLD        5
 143
 144 /* iterative version */
 145
 146 void wx_quadratic_spline(double a1, double b1, double a2, double b2, double a3, double b3, double a4,
 147                  double b4)
 148 {
 149     register double  xmid, ymid;
 150     double           x1, y1, x2, y2, x3, y3, x4, y4;
 151
 152     wx_clear_stack();
 153     wx_spline_push(a1, b1, a2, b2, a3, b3, a4, b4);
 154
 155     while (wx_spline_pop(&x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4)) {
 156         xmid = (double)half(x2, x3);
 157         ymid = (double)half(y2, y3);
 158         if (fabs(x1 - xmid) < THRESHOLD && fabs(y1 - ymid) < THRESHOLD &&
 159             fabs(xmid - x4) < THRESHOLD && fabs(ymid - y4) < THRESHOLD) {
 160             wx_spline_add_point( x1, y1 );
 161             wx_spline_add_point( xmid, ymid );
 162         } else {
 163             wx_spline_push(xmid, ymid, (double)half(xmid, x3), (double)half(ymid, y3),
 164                  (double)half(x3, x4), (double)half(y3, y4), x4, y4);
 165             wx_spline_push(x1, y1, (double)half(x1, x2), (double)half(y1, y2),
 166                  (double)half(x2, xmid), (double)half(y2, ymid), xmid, ymid);
 167         }
 168     }
 169 }
 170
 171 /* utilities used by spline drawing routines */
 172
 173 typedef struct wx_spline_stack_struct {
 174     double           x1, y1, x2, y2, x3, y3, x4, y4;
 175 } Stack;
 176
 177 #define         SPLINE_STACK_DEPTH             20
 178 static Stack    wx_spline_stack[SPLINE_STACK_DEPTH];
 179 static Stack   *wx_stack_top;
 180 static int      wx_stack_count;
 181
 182 void wx_clear_stack()
 183 {
 184     wx_stack_top = wx_spline_stack;
 185     wx_stack_count = 0;
 186 }
 187
 188 void wx_spline_push(double x1, double y1, double x2, double y2, double x3, double y3, double x4, double y4)
 189 {
 190     wx_stack_top->x1 = x1;
 191     wx_stack_top->y1 = y1;
 192     wx_stack_top->x2 = x2;
 193     wx_stack_top->y2 = y2;
 194     wx_stack_top->x3 = x3;
 195     wx_stack_top->y3 = y3;
 196     wx_stack_top->x4 = x4;
 197     wx_stack_top->y4 = y4;
 198     wx_stack_top++;
 199     wx_stack_count++;
 200 }
 201
 202 int wx_spline_pop(double *x1, double *y1, double *x2, double *y2,
 203                   double *x3, double *y3, double *x4, double *y4)
 204 {
 205     if (wx_stack_count == 0)
 206         return (0);
 207     wx_stack_top--;
 208     wx_stack_count--;
 209     *x1 = wx_stack_top->x1;
 210     *y1 = wx_stack_top->y1;
 211     *x2 = wx_stack_top->x2;
 212     *y2 = wx_stack_top->y2;
 213     *x3 = wx_stack_top->x3;
 214     *y3 = wx_stack_top->y3;
 215     *x4 = wx_stack_top->x4;
 216     *y4 = wx_stack_top->y4;
 217     return (1);
 218 }
 219
 220 static bool wx_spline_add_point(double x, double y)
 221 {
 222   wxPoint *point = new wxPoint ;
 223   point->x = (int) x;
 224   point->y = (int) y;
 225   wx_spline_point_list.Append((wxObject*)point);
 226   return TRUE;
 227 }
 228
 229 static void wx_spline_draw_point_array(wxDCBase *dc)
 230 {
 231   dc->DrawLines(&wx_spline_point_list, 0, 0 );
 232   wxNode *node = wx_spline_point_list.First();
 233   while (node)
 234   {
 235     wxPoint *point = (wxPoint *)node->Data();
 236     delete point;
 237     delete node;
 238     node = wx_spline_point_list.First();
 239   }
 240 }
 241
 242 void wxDCBase::DoDrawSpline( wxList *points )
 243 {
 244     wxCHECK_RET( Ok(), wxT("invalid window dc") );
 245
 246     wxPoint *p;
 247     double           cx1, cy1, cx2, cy2, cx3, cy3, cx4, cy4;
 248     double           x1, y1, x2, y2;
 249
 250     wxNode *node = points->First();
 251     p = (wxPoint *)node->Data();
 252
 253     x1 = p->x;
 254     y1 = p->y;
 255
 256     node = node->Next();
 257     p = (wxPoint *)node->Data();
 258
 259     x2 = p->x;
 260     y2 = p->y;
 261     cx1 = (double)((x1 + x2) / 2);
 262     cy1 = (double)((y1 + y2) / 2);
 263     cx2 = (double)((cx1 + x2) / 2);
 264     cy2 = (double)((cy1 + y2) / 2);
 265
 266     wx_spline_add_point(x1, y1);
 267
 268     while ((node = node->Next()) != NULL)
 269     {
 270         p = (wxPoint *)node->Data();
 271         x1 = x2;
 272         y1 = y2;
 273         x2 = p->x;
 274         y2 = p->y;
 275         cx4 = (double)(x1 + x2) / 2;
 276         cy4 = (double)(y1 + y2) / 2;
 277         cx3 = (double)(x1 + cx4) / 2;
 278         cy3 = (double)(y1 + cy4) / 2;
 279
 280         wx_quadratic_spline(cx1, cy1, cx2, cy2, cx3, cy3, cx4, cy4);
 281
 282         cx1 = cx4;
 283         cy1 = cy4;
 284         cx2 = (double)(cx1 + x2) / 2;
 285         cy2 = (double)(cy1 + y2) / 2;
 286     }
 287
 288     wx_spline_add_point( cx1, cy1 );
 289     wx_spline_add_point( x2, y2 );
 290
 291     wx_spline_draw_point_array( this );
 292 }
 293
 294 #endif // wxUSE_SPLINES