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