src/msw/xfspline.inc

   1 /*
   2  * File:        xfspline.cc
   3  * Purpose:
   4  * Author:      Julian Smart
   5  * Created:     1993
   6  * Updated:     August 1994
   7  * RCS_ID:      $Id$
   8  * Copyright:   (c) 1993, AIAI, University of Edinburgh
   9  */
  10
  11 // Must be a comment as this file is #include\'d by wb_dc.cc
  12 /* static const char sccsid[] = "@(#)xfspline.cc        1.3 5/9/94"; */
  13
  14 /*
  15  * FIG : Facility for Interactive Generation of figures
  16  * Copyright (c) 1985 by Supoj Sutanthavibul
  17  */
  18
  19
  20 #if USE_SPLINES
  21
  22 ////#define     wx_round(a)    (int)((a)+.5)
  23 //#define     wx_round(a)    (a)
  24
  25 class wxSpline: public wxObject
  26 {
  27  public:
  28   int type;
  29   wxList *points;
  30
  31   wxSpline(wxList *list);
  32   void DeletePoints(void);
  33
  34   // Doesn't delete points
  35   ~wxSpline(void);
  36 };
  37
  38 void wx_draw_open_spline(wxDC *dc, wxSpline *spline);
  39
  40 #if USE_POSTSCRIPT
  41 void wx_draw_open_spline_ps(wxPostScriptDC *dc, wxSpline *s);
  42 #endif
  43
  44 void wx_quadratic_spline(double a1, double b1, double a2, double b2,
  45                          double a3, double b3, double a4, double b4);
  46 void wx_clear_stack(void);
  47 int wx_spline_pop(double *x1, double *y1, double *x2, double *y2, double *x3,
  48         double *y3, double *x4, double *y4);
  49 void wx_spline_push(double x1, double y1, double x2, double y2, double x3, double y3,
  50           double x4, double y4);
  51 static bool wx_spline_add_point(double x, double y);
  52 static void wx_spline_draw_point_array(wxDC *dc);
  53 wxSpline *wx_make_spline(int x1, int y1, int x2, int y2, int x3, int y3);
  54
  55 void wxDC::DrawSpline(int n, wxPoint points[])
  56 {
  57   wxList list;
  58   int i;
  59   for (i =0; i < n; i++)
  60     list.Append((wxObject*)&points[i]);
  61   DrawSpline((wxList *)&list);
  62 }
  63
  64 void wxDC::DrawSpline(wxList *list)
  65 {
  66   wxSpline spline(list);
  67
  68   wx_draw_open_spline(this, &spline);
  69 }
  70
  71
  72 wxList wx_spline_point_list;
  73
  74 void wx_draw_open_spline(wxDC *dc, wxSpline *spline)
  75 {
  76     wxPoint *p;
  77     double           cx1, cy1, cx2, cy2, cx3, cy3, cx4, cy4;
  78     double           x1, y1, x2, y2;
  79
  80     wxNode *node = spline->points->First();
  81     p = (wxPoint *)node->Data();
  82
  83     x1 = p->x;
  84     y1 = p->y;
  85
  86     node = node->Next();
  87     p = (wxPoint *)node->Data();
  88
  89     x2 = p->x;
  90     y2 = p->y;
  91     cx1 = (double)((x1 + x2) / 2);
  92     cy1 = (double)((y1 + y2) / 2);
  93     cx2 = (double)((cx1 + x2) / 2);
  94     cy2 = (double)((cy1 + y2) / 2);
  95
  96     wx_spline_add_point(x1, y1);
  97
  98     while ((node = node->Next()) != NULL)
  99     {
 100         p = (wxPoint *)node->Data();
 101         x1 = x2;
 102         y1 = y2;
 103         x2 = p->x;
 104         y2 = p->y;
 105         cx4 = (double)(x1 + x2) / 2;
 106         cy4 = (double)(y1 + y2) / 2;
 107         cx3 = (double)(x1 + cx4) / 2;
 108         cy3 = (double)(y1 + cy4) / 2;
 109
 110         wx_quadratic_spline(cx1, cy1, cx2, cy2, cx3, cy3, cx4, cy4);
 111
 112         cx1 = cx4;
 113         cy1 = cy4;
 114         cx2 = (double)(cx1 + x2) / 2;
 115         cy2 = (double)(cy1 + y2) / 2;
 116     }
 117
 118     wx_spline_add_point((double)wx_round(cx1), (double)wx_round(cy1));
 119     wx_spline_add_point(x2, y2);
 120
 121     wx_spline_draw_point_array(dc);
 122
 123 }
 124
 125 #if USE_POSTSCRIPT
 126 void wx_draw_open_spline_ps(wxPostScriptDC *dc, wxSpline *s)
 127 {
 128         double          a, b, c, d, x1, y1, x2, y2, x3, y3;
 129         wxPoint *p, *q;
 130         if (dc->GetAutoSetting())
 131           dc->SetPen(* dc->GetPen());
 132
 133         wxNode *node = s->points->First();
 134         p = (wxPoint *)node->Data();
 135
 136         x1 = p->x; y1 = p->y;
 137
 138         node = node->Next();
 139         p = (wxPoint *)node->Data();
 140         c = p->x; d = p->y;
 141         x3 = a = (double)(x1 + c) / 2;
 142         y3 = b = (double)(y1 + d) / 2;
 143
 144         *(dc->GetStream()) << "newpath " << x1 << " " << dc->GetYOrigin() - y1 << " moveto " << x3 << " " << dc->GetYOrigin() - y3;
 145         *(dc->GetStream()) << " lineto\n";
 146         dc->CalcBoundingBox((double)x1, (double)(dc->GetYOrigin() - y1));
 147         dc->CalcBoundingBox((double)x3, (double)(dc->GetYOrigin() - y3));
 148
 149         while ((node = node->Next()) != NULL)
 150         {
 151           q = (wxPoint *)node->Data();
 152
 153           x1 = x3; y1 = y3;
 154           x2 = c;  y2 = d;
 155           c = q->x; d = q->y;
 156           x3 = (double)(x2 + c) / 2;
 157           y3 = (double)(y2 + d) / 2;
 158           *(dc->GetStream()) << x1 << " " << dc->GetYOrigin() - y1 << " " << x2 << " " << dc->GetYOrigin() - y2 << " ";
 159           *(dc->GetStream()) << x3 << " " << dc->GetYOrigin() - y3 << " DrawSplineSection\n";
 160
 161           dc->CalcBoundingBox((double)x1, (double)(dc->GetYOrigin() - y1));
 162           dc->CalcBoundingBox((double)x3, (double)(dc->GetYOrigin() - y3));
 163         }
 164         /*
 165         * At this point, (x2,y2) and (c,d) are the position of the
 166         * next-to-last and last point respectively, in the point list
 167         */
 168         *(dc->GetStream()) << c << " " << dc->GetYOrigin() - d << " lineto stroke\n";
 169 }
 170 #endif
 171
 172 /********************* CURVES FOR SPLINES *****************************
 173
 174         The following spline drawing routine is from
 175
 176         "An Algorithm for High-Speed Curve Generation"
 177         by George Merrill Chaikin,
 178         Computer Graphics and Image Processing, 3, Academic Press,
 179         1974, 346-349.
 180
 181         and
 182
 183         "On Chaikin's Algorithm" by R. F. Riesenfeld,
 184         Computer Graphics and Image Processing, 4, Academic Press,
 185         1975, 304-310.
 186
 187 ***********************************************************************/
 188
 189 #define         half(z1, z2)    ((z1+z2)/2.0)
 190 #define         THRESHOLD       5
 191
 192 /* iterative version */
 193
 194 void wx_quadratic_spline(double a1, double b1, double a2, double b2, double a3, double b3, double a4,
 195                  double b4)
 196 {
 197     register double  xmid, ymid;
 198     double           x1, y1, x2, y2, x3, y3, x4, y4;
 199
 200     wx_clear_stack();
 201     wx_spline_push(a1, b1, a2, b2, a3, b3, a4, b4);
 202
 203     while (wx_spline_pop(&x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4)) {
 204         xmid = (double)half(x2, x3);
 205         ymid = (double)half(y2, y3);
 206         if (fabs(x1 - xmid) < THRESHOLD && fabs(y1 - ymid) < THRESHOLD &&
 207             fabs(xmid - x4) < THRESHOLD && fabs(ymid - y4) < THRESHOLD) {
 208             wx_spline_add_point((double)wx_round(x1), (double)wx_round(y1));
 209             wx_spline_add_point((double)wx_round(xmid), (double)wx_round(ymid));
 210         } else {
 211             wx_spline_push(xmid, ymid, (double)half(xmid, x3), (double)half(ymid, y3),
 212                  (double)half(x3, x4), (double)half(y3, y4), x4, y4);
 213             wx_spline_push(x1, y1, (double)half(x1, x2), (double)half(y1, y2),
 214                  (double)half(x2, xmid), (double)half(y2, ymid), xmid, ymid);
 215         }
 216     }
 217 }
 218
 219
 220 /* utilities used by spline drawing routines */
 221
 222
 223 typedef struct wx_spline_stack_struct {
 224     double           x1, y1, x2, y2, x3, y3, x4, y4;
 225 }
 226                 Stack;
 227
 228 #define         SPLINE_STACK_DEPTH             20
 229 static Stack    wx_spline_stack[SPLINE_STACK_DEPTH];
 230 static Stack   *wx_stack_top;
 231 static int      wx_stack_count;
 232
 233 void wx_clear_stack(void)
 234 {
 235     wx_stack_top = wx_spline_stack;
 236     wx_stack_count = 0;
 237 }
 238
 239 void wx_spline_push(double x1, double y1, double x2, double y2, double x3, double y3, double x4, double y4)
 240 {
 241     wx_stack_top->x1 = x1;
 242     wx_stack_top->y1 = y1;
 243     wx_stack_top->x2 = x2;
 244     wx_stack_top->y2 = y2;
 245     wx_stack_top->x3 = x3;
 246     wx_stack_top->y3 = y3;
 247     wx_stack_top->x4 = x4;
 248     wx_stack_top->y4 = y4;
 249     wx_stack_top++;
 250     wx_stack_count++;
 251 }
 252
 253 int wx_spline_pop(double *x1, double *y1, double *x2, double *y2,
 254                   double *x3, double *y3, double *x4, double *y4)
 255 {
 256     if (wx_stack_count == 0)
 257         return (0);
 258     wx_stack_top--;
 259     wx_stack_count--;
 260     *x1 = wx_stack_top->x1;
 261     *y1 = wx_stack_top->y1;
 262     *x2 = wx_stack_top->x2;
 263     *y2 = wx_stack_top->y2;
 264     *x3 = wx_stack_top->x3;
 265     *y3 = wx_stack_top->y3;
 266     *x4 = wx_stack_top->x4;
 267     *y4 = wx_stack_top->y4;
 268     return (1);
 269 }
 270
 271 static bool wx_spline_add_point(double x, double y)
 272 {
 273   wxPoint *point = new wxPoint ;
 274   point->x = (int) x;
 275   point->y = (int) y;
 276   wx_spline_point_list.Append((wxObject*)point);
 277   return TRUE;
 278 }
 279
 280 static void wx_spline_draw_point_array(wxDC *dc)
 281 {
 282   dc->DrawLines(&wx_spline_point_list, (double)0.0, (double)0.0);
 283   wxNode *node = wx_spline_point_list.First();
 284   while (node)
 285   {
 286     wxPoint *point = (wxPoint *)node->Data();
 287     delete point;
 288     delete node;
 289     node = wx_spline_point_list.First();
 290   }
 291 }
 292
 293 wxSpline::wxSpline(wxList *list)
 294 {
 295   points = list;
 296 }
 297
 298 wxSpline::~wxSpline(void)
 299 {
 300 }
 301
 302 void wxSpline::DeletePoints(void)
 303 {
 304   for(wxNode *node = points->First(); node; node = points->First())
 305   {
 306     wxPoint *point = (wxPoint *)node->Data();
 307     delete point;
 308     delete node;
 309   }
 310   delete points;
 311 }
 312
 313 #if USE_POSTSCRIPT
 314
 315 // Make a 3-point spline
 316 void wxPostScriptDC::DrawSpline(long x1, long y1, long x2, long y2, long x3, long y3)
 317 {
 318   wxList *point_list = new wxList;
 319
 320   wxPoint *point1 = new wxPoint;
 321   point1->x = x1; point1->y = y1;
 322   point_list->Append((wxObject*)point1);
 323
 324   wxPoint *point2 = new wxPoint;
 325   point2->x = x2; point2->y = y2;
 326   point_list->Append((wxObject*)point2);
 327
 328   wxPoint *point3 = new wxPoint;
 329   point3->x = x3; point3->y = y3;
 330   point_list->Append((wxObject*)point3);
 331
 332   wxSpline spline(point_list);
 333
 334   wx_draw_open_spline_ps(this, &spline);
 335   spline.DeletePoints();
 336 }
 337
 338 void wxPostScriptDC::DrawSpline(wxList *list)
 339 {
 340   wxSpline spline(list);
 341
 342   wx_draw_open_spline_ps(this, &spline);
 343 }
 344
 345 void wxPostScriptDC::DrawSpline(int n, wxPoint points[])
 346 {
 347   wxList list;
 348   int i;
 349   for (i =0; i < n; i++)
 350     list.Append((wxObject*)&points[i]);
 351   DrawSpline((wxList *)&list);
 352 }
 353
 354
 355 #endif // USE_POSTSCRIPT
 356
 357 #endif // USE_SPLINES
 358