demos/objects/objects-community.c

   1 #include "cll1.h"
   2
   3 /* This is example of advanced C<<1 object oriented features... */
   4
   5 def_type(Shape);
   6
   7 def_mem(Interface)
   8 {
   9  void method(draw) (Shape self);
  10  void method(move) (Shape self, int x, int y);
  11  str method(desc) (Shape self);
  12  void method(rename) (Shape self, str name);
  13  void method(reset) (Shape self, int x1, int y1, int x2, int y2, int x3, int y3);
  14  float method(area) (Shape self);
  15  int count;
  16 };
  17
  18 /* We intentionaly define heterogenous objects, which share only the interface
  19    binding. Not only we can use different order of variables, and different
  20    names - but we can even store these data on remote systems, etc.  */
  21
  22 def_mem(Tri)
  23 {
  24  interface(Interface);
  25  int x1, y1, x2, y2, x3, y3;
  26  str name;
  27 };
  28
  29 def_mem(Rect)
  30 {
  31  interface(Interface);
  32  str desc;
  33  int x1, y1, x2, y2;
  34 };
  35
  36 def_mem(Circ)
  37 {
  38  interface(Interface);
  39  int x1, y1;
  40  str comment;
  41  int r;
  42 };
  43
  44 def_community(Shape, Interface);
  45
  46 /* Note: interface(Interface); has to be at first position in all objects asociated in community */
  47
  48 def_mem(Object_list)
  49 {
  50  Shape object;
  51  list(Object_list);
  52 };
  53
  54
  55 /* implementation of methods */
  56
  57 void drawTri(Shape community)
  58 {
  59  I_am(self, Tri);
  60
  61  printf("Drawing %s: %d,%d - %d,%d - %d,%d .\n",
  62         self->name, self->x1, self->y1, self->x2, self->y2, self->x3, self->y3);
  63 };
  64
  65 void drawRect(Shape community)
  66 {
  67  I_am(self, Rect);
  68
  69  printf("Drawing %s: %d,%d - %d,%d .\n",
  70         self->desc, self->x1, self->y1, self->x2, self->y2);
  71 };
  72
  73 void drawCirc(Shape community)
  74 {
  75  I_am(self, Circ);
  76
  77  printf("Drawing %s: %d,%d - r=%d .\n",
  78         self->comment, self->x1, self->y1, self->r);
  79 };
  80
  81 void moveTri(Shape community, int x, int y)
  82 {
  83  I_am(self, Tri);
  84
  85  self->x1 += x;
  86  self->y1 += y;
  87  self->x2 += x;
  88  self->y2 += y;
  89  self->x3 += x;
  90  self->y3 += y;
  91 };
  92
  93 void moveRect(Shape community, int x, int y)
  94 {
  95  I_am(self, Rect);
  96
  97  self->x1 += x;
  98  self->y1 += y;
  99  self->x2 += x;
 100  self->y2 += y;
 101 };
 102
 103 void moveCirc(Shape community, int x, int y)
 104 {
 105  I_am(self, Circ);
 106
 107  self->x1 += x;
 108  self->y1 += y;
 109 };
 110
 111 str descTri(Shape community)
 112 {
 113  I_am(self, Tri);
 114
 115  return self->name;
 116 }
 117
 118 str descRect(Shape community)
 119 {
 120  I_am(self, Rect);
 121
 122  return self->desc;
 123 }
 124
 125 str descCirc(Shape community)
 126 {
 127  I_am(self, Circ);
 128
 129  return self->comment;
 130 }
 131
 132 float calcAreaTri(Shape community)
 133 {
 134  I_am(self, Tri);
 135
 136  return 0;
 137 }
 138
 139 float calcAreaRect(Shape community)
 140 {
 141  I_am(self, Rect);
 142
 143  return (self->x2 - self->x1)*(self->y2 - self->y1);
 144 }
 145
 146 float calcAreaCirc(Shape community)
 147 {
 148  I_am(self, Circ);
 149
 150  return PI * self->r * self->r;
 151 }
 152
 153 void setTri(Shape community, int x1, int y1, int x2, int y2, int x3, int y3)
 154 {
 155  I_am(self, Tri);
 156
 157  self->x1 = x1;
 158  self->y1 = y1;
 159  self->x2 = x2;
 160  self->y2 = y2;
 161  self->x3 = x3;
 162  self->y3 = y3;
 163 }
 164
 165 void setRect(Shape community, int x1, int y1, int x2, int y2, int dummy1, int dummy2)
 166 {
 167  I_am(self, Rect);
 168
 169  self->x1 = x1;
 170  self->y1 = y1;
 171  self->x2 = x2;
 172  self->y2 = y2;
 173 }
 174
 175 void setCirc(Shape community, int x1, int y1, int r, int dummy1, int dummy2, int dummy3)
 176 {
 177  I_am(self, Circ);
 178
 179  self->x1 = x1;
 180  self->y1 = y1;
 181  self->r = r;
 182 }
 183
 184 void nameRect(Shape community, str name)
 185 {
 186  I_am(self, Rect);
 187
 188  self->desc = name;
 189 }
 190
 191 /* Example of using object interface methods from inside constructor methods */
 192
 193 construct(Tri,Interface) (Tri self, int x1, int y1, int x2, int y2, int x3, int y3)
 194 {
 195  self->name = "TRIANGLE";
 196  interface_of(self)->count++;
 197  _(reset, self, x1, y1, x2, y2, x3, y3);
 198
 199  return self;
 200 }
 201
 202 construct(Rect,Interface) (Rect self, int x1, int y1, int x2, int y2)
 203 {
 204  self->desc = "rectangle";
 205  interface_of(self)->count++;
 206  _(reset, self, x1, y1, x2, y2, 0, 0);
 207
 208  return self;
 209 }
 210
 211 construct(Circ,Interface) (Circ self, int x1, int y1, int r)
 212 {
 213  self->comment = "Circle";
 214  interface_of(self)->count++;
 215  _(reset, self, x1, y1, r, 0, 0, 0);
 216
 217  return self;
 218 }
 219
 220 /* registration of implemented methods to three interfaces of the same type */
 221
 222 Interface triInterface(void)
 223 {
 224  Get_mem(this, Interface);
 225
 226  this->draw = drawTri;
 227  this->move = moveTri;
 228  this->desc = descTri;
 229  this->rename = NULL;
 230  this->reset = setTri;
 231  this->area = calcAreaTri;
 232  this->count = 0;
 233
 234  return this;
 235 }
 236
 237 Interface rectInterface(void)
 238 {
 239  Get_mem(this, Interface);
 240
 241  this->draw = drawRect;
 242  this->move = moveRect;
 243  this->desc = descRect;
 244  this->rename = nameRect;
 245  this->reset = setRect;
 246  this->area = calcAreaRect;
 247  this->count = 0;
 248
 249  return this;
 250 }
 251
 252 Interface circInterface(void)
 253 {
 254  Get_mem(this, Interface);
 255
 256  this->draw = drawCirc;
 257  this->move = moveCirc;
 258  this->desc = descCirc;
 259  this->rename = NULL;
 260  this->reset = setCirc;
 261  this->area = calcAreaCirc;
 262  this->count = 0;
 263
 264  return this;
 265 }
 266
 267 /* usage of objects inside C<<1 program */
 268
 269 program
 270 {
 271  Interface triangles = triInterface();
 272  Interface rectangles = rectInterface();
 273  Interface circles = circInterface();
 274  Object_list all = NULL, one;
 275
 276  one = get_mem(Object_list);
 277  one->object = get_obj_as(Shape, Rect, rectangles, 0, 10, 1, 11);
 278  append(one, all);
 279
 280  one = get_mem(Object_list);
 281  one->object = get_obj_as(Shape, Tri, triangles, 0, 0, 0, 4, 3, 0);
 282  append(one, all);
 283
 284  one = get_mem(Object_list);
 285  one->object = get_obj_as(Shape, Rect, rectangles, 10, 0, 11, 1);
 286  append(one, all);
 287
 288  one = get_mem(Object_list);
 289  one->object = get_obj_as(Shape, Circ, circles, 0, 10, 1);
 290  append(one, all);
 291
 292  printf("We have created %d triangles, %d rectangles and %d circles:\n",
 293         triangles->count, rectangles->count, circles->count);
 294
 295  for_each(one, all)
 296  {
 297   _(draw, one->object);
 298   printf("Area of this %s is %f (square pixels).\n", _(desc, one->object), _(area, one->object));
 299   printf("We have created %d instances of this type of object.\n", interface_of(one->object)->count);
 300
 301   if(interface_of(one->object) == rectangles)
 302   {
 303    _(reset, one->object, 0, 0, 1, 1, 0, 0);
 304    _(rename, one->object, "Renamed rectangle");
 305   }
 306   else
 307   {
 308    _(move, one->object, 10, 10);
 309   }
 310  }
 311
 312  print("Rectangles were reset to new size and renamed, other objects were moved:");
 313  for_each(one, all)
 314  {
 315   _(draw, one->object);
 316  }
 317 }