objects/standard/line.c

   1 /* Dia -- an diagram creation/manipulation program
   2  * Copyright (C) 1998 Alexander Larsson
   3  * Copyright (C) 2002 David Hoover
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include <config.h>
  22 #endif
  23
  24 #include <assert.h>
  25 #include <math.h>
  26
  27 #include "intl.h"
  28 #include "object.h"
  29 #include "connection.h"
  30 #include "connectionpoint.h"
  31 #include "diarenderer.h"
  32 #include "attributes.h"
  33 #include "widgets.h"
  34 #include "arrows.h"
  35 #include "connpoint_line.h"
  36 #include "properties.h"
  37
  38 #include "tool-icons.h"
  39
  40 #define DEFAULT_WIDTH 0.25
  41
  42 typedef struct _LineProperties LineProperties;
  43
  44 typedef struct _Line {
  45   Connection connection;
  46
  47   ConnPointLine *cpl;
  48
  49   Color line_color;
  50   real line_width;
  51   LineStyle line_style;
  52   Arrow start_arrow, end_arrow;
  53   real dashlength;
  54   real absolute_start_gap, absolute_end_gap;
  55 } Line;
  56
  57 struct _LineProperties {
  58   real absolute_start_gap, absolute_end_gap;
  59 };
  60
  61 static LineProperties default_properties;
  62
  63 static ObjectChange* line_move_handle(Line *line, Handle *handle,
  64                                       Point *to, ConnectionPoint *cp,
  65                                       HandleMoveReason reason,
  66                              ModifierKeys modifiers);
  67 static ObjectChange* line_move(Line *line, Point *to);
  68 static void line_select(Line *line, Point *clicked_point,
  69                         DiaRenderer *interactive_renderer);
  70 static void line_draw(Line *line, DiaRenderer *renderer);
  71 static DiaObject *line_create(Point *startpoint,
  72                            void *user_data,
  73                            Handle **handle1,
  74                            Handle **handle2);
  75 static real line_distance_from(Line *line, Point *point);
  76 static void line_update_data(Line *line);
  77 static void line_destroy(Line *line);
  78 static DiaObject *line_copy(Line *line);
  79
  80 static PropDescription *line_describe_props(Line *line);
  81 static void line_get_props(Line *line, GPtrArray *props);
  82 static void line_set_props(Line *line, GPtrArray *props);
  83
  84 static void line_save(Line *line, ObjectNode obj_node, const char *filename);
  85 static DiaObject *line_load(ObjectNode obj_node, int version, const char *filename);
  86 static DiaMenu *line_get_object_menu(Line *line, Point *clickedpoint);
  87
  88 void Line_adjust_for_absolute_gap(Line *line, Point *gap_endpoints);
  89
  90 static ObjectTypeOps line_type_ops =
  91 {
  92   (CreateFunc) line_create,
  93   (LoadFunc)   line_load,
  94   (SaveFunc)   line_save,
  95   (GetDefaultsFunc)   NULL,
  96   (ApplyDefaultsFunc) NULL
  97 };
  98
  99 DiaObjectType line_type =
 100 {
 101   "Standard - Line",   /* name */
 102   0,                   /* version */
 103   (char **) line_icon,  /* pixmap */
 104   &line_type_ops       /* ops */
 105 };
 106
 107 DiaObjectType *_line_type = (DiaObjectType *) &line_type;
 108
 109 static ObjectOps line_ops = {
 110   (DestroyFunc)         line_destroy,
 111   (DrawFunc)            line_draw,
 112   (DistanceFunc)        line_distance_from,
 113   (SelectFunc)          line_select,
 114   (CopyFunc)            line_copy,
 115   (MoveFunc)            line_move,
 116   (MoveHandleFunc)      line_move_handle,
 117   (GetPropertiesFunc)   object_create_props_dialog,
 118   (ApplyPropertiesFunc) object_apply_props_from_dialog,
 119   (ObjectMenuFunc)      line_get_object_menu,
 120   (DescribePropsFunc)   line_describe_props,
 121   (GetPropsFunc)        line_get_props,
 122   (SetPropsFunc)        line_set_props
 123 };
 124
 125 static PropNumData gap_range = { -G_MAXFLOAT, G_MAXFLOAT, 0.1};
 126
 127 static PropDescription line_props[] = {
 128   OBJECT_COMMON_PROPERTIES,
 129   PROP_STD_LINE_WIDTH,
 130   PROP_STD_LINE_COLOUR,
 131   PROP_STD_LINE_STYLE,
 132   PROP_FRAME_BEGIN("arrows",PROP_FLAG_STANDARD,N_("Arrows")),
 133   PROP_STD_START_ARROW,
 134   PROP_STD_END_ARROW,
 135   PROP_FRAME_END("arrows",PROP_FLAG_STANDARD),
 136   { "start_point", PROP_TYPE_POINT, 0,
 137     N_("Start point"), NULL },
 138   { "end_point", PROP_TYPE_POINT, 0,
 139     N_("End point"), NULL },
 140
 141   PROP_FRAME_BEGIN("gaps",0,N_("Line gaps")),
 142   { "absolute_start_gap", PROP_TYPE_REAL, PROP_FLAG_VISIBLE,
 143     N_("Absolute start gap"), NULL, &gap_range },
 144   { "absolute_end_gap", PROP_TYPE_REAL, PROP_FLAG_VISIBLE,
 145     N_("Absolute end gap"), NULL, &gap_range },
 146   PROP_FRAME_END("gaps",0),
 147
 148   PROP_DESC_END
 149 };
 150
 151 static PropDescription *
 152 line_describe_props(Line *line)
 153 {
 154   if (line_props[0].quark == 0)
 155     prop_desc_list_calculate_quarks(line_props);
 156   return line_props;
 157 }
 158
 159 static PropOffset line_offsets[] = {
 160   OBJECT_COMMON_PROPERTIES_OFFSETS,
 161   { "line_width", PROP_TYPE_REAL, offsetof(Line, line_width) },
 162   { "line_colour", PROP_TYPE_COLOUR, offsetof(Line, line_color) },
 163   { "line_style", PROP_TYPE_LINESTYLE,
 164     offsetof(Line, line_style), offsetof(Line, dashlength) },
 165   { "start_arrow", PROP_TYPE_ARROW, offsetof(Line, start_arrow) },
 166   { "end_arrow", PROP_TYPE_ARROW, offsetof(Line, end_arrow) },
 167   { "start_point", PROP_TYPE_POINT, offsetof(Connection, endpoints[0]) },
 168   { "end_point", PROP_TYPE_POINT, offsetof(Connection, endpoints[1]) },
 169   { "absolute_start_gap", PROP_TYPE_REAL, offsetof(Line, absolute_start_gap) },
 170   { "absolute_end_gap", PROP_TYPE_REAL, offsetof(Line, absolute_end_gap) },
 171   { NULL, 0, 0 }
 172 };
 173
 174 static void
 175 line_get_props(Line *line, GPtrArray *props)
 176 {
 177   object_get_props_from_offsets(&line->connection.object,
 178                                 line_offsets, props);
 179 }
 180
 181 static void
 182 line_set_props(Line *line, GPtrArray *props)
 183 {
 184   object_set_props_from_offsets(&line->connection.object,
 185                                 line_offsets, props);
 186   line_update_data(line);
 187 }
 188
 189 static void
 190 line_init_defaults() {
 191   static int defaults_initialized = 0;
 192
 193   if (!defaults_initialized) {
 194     default_properties.absolute_start_gap = 0.0;
 195     default_properties.absolute_end_gap = 0.0;
 196     defaults_initialized = 1;
 197   }
 198 }
 199
 200 static ObjectChange *
 201 line_add_connpoint_callback(DiaObject *obj, Point *clicked, gpointer data)
 202 {
 203   ObjectChange *oc;
 204   oc = connpointline_add_point(((Line *)obj)->cpl,clicked);
 205   line_update_data((Line *)obj);
 206   return oc;
 207 }
 208
 209 static ObjectChange *
 210 line_remove_connpoint_callback(DiaObject *obj, Point *clicked, gpointer data)
 211 {
 212   ObjectChange *oc;
 213   oc = connpointline_remove_point(((Line *)obj)->cpl,clicked);
 214   line_update_data((Line *)obj);
 215   return oc;
 216 }
 217
 218 static DiaMenuItem object_menu_items[] = {
 219   { N_("Add connection point"), line_add_connpoint_callback, NULL, 1 },
 220   { N_("Delete connection point"), line_remove_connpoint_callback,
 221     NULL, 1 },
 222 };
 223
 224 static DiaMenu object_menu = {
 225   N_("Line"),
 226   sizeof(object_menu_items)/sizeof(DiaMenuItem),
 227   object_menu_items,
 228   NULL
 229 };
 230
 231 static DiaMenu *
 232 line_get_object_menu(Line *line, Point *clickedpoint)
 233 {
 234   ConnPointLine *cpl;
 235
 236   cpl = line->cpl;
 237   /* Set entries sensitive/selected etc here */
 238   object_menu_items[0].active =
 239     connpointline_can_add_point(cpl, clickedpoint);
 240   object_menu_items[1].active =
 241     connpointline_can_remove_point(cpl,clickedpoint);
 242   return &object_menu;
 243 }
 244
 245 /*
 246   About start_gap, end_gap, auto/absolute
 247
 248   Place positive reals (try 1.0, for instance) in absolute
 249   to create gaps on line end/start.
 250   If auto_gap is false, these gaps are of that length.
 251   If a gap is negative, the line extends past the handle.
 252   If auto_gap is true, the gap length is computed so it touches
 253   the connected object edge then the absolute gap is added
 254   */
 255
 256 Point
 257 calculate_object_edge(Point *objmid, Point *end, DiaObject *obj)
 258 {
 259 #define MAXITER 25
 260 #ifdef TRACE_DIST
 261   Point trace[MAXITER];
 262   real disttrace[MAXITER];
 263 #endif
 264   Point mid1, mid2, mid3;
 265   real dist;
 266   int i = 0;
 267
 268   mid1 = *objmid;
 269   mid2.x = (objmid->x+end->x)/2;
 270   mid2.y = (objmid->y+end->y)/2;
 271   mid3 = *end;
 272
 273   /* If the other end is inside the object */
 274   dist = obj->ops->distance_from(obj, &mid3);
 275   if (dist < 0.001) return mid1;
 276
 277
 278   do {
 279     dist = obj->ops->distance_from(obj, &mid2);
 280     if (dist < 0.0000001) {
 281       mid1 = mid2;
 282     } else {
 283       mid3 = mid2;
 284     }
 285     mid2.x = (mid1.x + mid3.x)/2;
 286     mid2.y = (mid1.y + mid3.y)/2;
 287 #ifdef TRACE_DIST
 288     trace[i] = mid2;
 289     disttrace[i] = dist;
 290 #endif
 291     i++;
 292   } while (i < MAXITER && (dist < 0.0000001 || dist > 0.001));
 293
 294 #ifdef TRACE_DIST
 295   if (i == MAXITER) {
 296     for (i = 0; i < MAXITER; i++) {
 297       printf("%d: %f, %f: %f\n", i, trace[i].x, trace[i].y, disttrace[i]);
 298     }
 299     printf("i = %d, dist = %f\n", i, dist);
 300   }
 301 #endif
 302
 303   return mid2;
 304 }
 305
 306
 307 /** Calculate the absolute gap -- this gap is 'transient', in that
 308  * the actual end of the line is not moved, but it is made to look like
 309  * it is shorter.
 310  */
 311 void
 312 line_adjust_for_absolute_gap(Line *line, Point *gap_endpoints)
 313 {
 314   Point endpoints[2];
 315   real line_length;
 316
 317   endpoints[0] = line->connection.endpoints[0];
 318   endpoints[1] = line->connection.endpoints[1];
 319
 320   line_length = distance_point_point(&endpoints[0], &endpoints[1]);
 321
 322   /* puts new 0 to x% of  0->1  */
 323   point_convex(&gap_endpoints[0], &endpoints[0], &endpoints[1],
 324               1 - line->absolute_start_gap/line_length);
 325
 326   /* puts new 1 to x% of  1->0  */
 327   point_convex(&gap_endpoints[1], &endpoints[1], &endpoints[0],
 328               1 - line->absolute_end_gap/line_length);
 329 }
 330
 331 static real
 332 line_distance_from(Line *line, Point *point)
 333 {
 334   Point *endpoints;
 335
 336   endpoints = &line->connection.endpoints[0];
 337
 338   if (line->absolute_start_gap || line->absolute_end_gap ) {
 339     Point gap_endpoints[2];  /* Visible endpoints of line */
 340
 341     line_adjust_for_absolute_gap(line, gap_endpoints);
 342     return distance_line_point( &gap_endpoints[0], &gap_endpoints[1],
 343                                line->line_width, point);
 344   } else {
 345     return distance_line_point( &endpoints[0], &endpoints[1],
 346                                line->line_width, point);
 347   }
 348 }
 349
 350 static void
 351 line_select(Line *line, Point *clicked_point,
 352             DiaRenderer *interactive_renderer)
 353 {
 354   connection_update_handles(&line->connection);
 355 }
 356
 357 static ObjectChange*
 358 line_move_handle(Line *line, Handle *handle,
 359                  Point *to, ConnectionPoint *cp,
 360                  HandleMoveReason reason, ModifierKeys modifiers)
 361 {
 362   assert(line!=NULL);
 363   assert(handle!=NULL);
 364   assert(to!=NULL);
 365
 366   connection_move_handle(&line->connection, handle->id, to, cp, reason, modifiers);
 367
 368   line_update_data(line);
 369
 370   return NULL;
 371 }
 372
 373 static ObjectChange*
 374 line_move(Line *line, Point *to)
 375 {
 376   Point start_to_end;
 377   Point *endpoints = &line->connection.endpoints[0];
 378
 379   start_to_end = endpoints[1];
 380   point_sub(&start_to_end, &endpoints[0]);
 381
 382   endpoints[1] = endpoints[0] = *to;
 383   point_add(&endpoints[1], &start_to_end);
 384
 385   line_update_data(line);
 386
 387   return NULL;
 388 }
 389
 390 static void
 391 line_draw(Line *line, DiaRenderer *renderer)
 392 {
 393   Point gap_endpoints[2];
 394
 395   DiaRendererClass *renderer_ops = DIA_RENDERER_GET_CLASS (renderer);
 396
 397   assert(line != NULL);
 398   assert(renderer != NULL);
 399
 400   renderer_ops->set_linewidth(renderer, line->line_width);
 401   renderer_ops->set_linestyle(renderer, line->line_style);
 402   renderer_ops->set_dashlength(renderer, line->dashlength);
 403   renderer_ops->set_linecaps(renderer, LINECAPS_BUTT);
 404
 405   if (line->absolute_start_gap || line->absolute_end_gap ) {
 406     line_adjust_for_absolute_gap(line, gap_endpoints);
 407
 408     renderer_ops->draw_line_with_arrows(renderer,
 409                                         &gap_endpoints[0], &gap_endpoints[1],
 410                                         line->line_width,
 411                                         &line->line_color,
 412                                         &line->start_arrow,
 413                                         &line->end_arrow);
 414   } else {
 415         renderer_ops->draw_line_with_arrows(renderer,
 416                                             &line->connection.endpoints[0],
 417                                             &line->connection.endpoints[1],
 418                                             line->line_width,
 419                                             &line->line_color,
 420                                             &line->start_arrow,
 421                                             &line->end_arrow);
 422
 423   }
 424 }
 425
 426 static DiaObject *
 427 line_create(Point *startpoint,
 428             void *user_data,
 429             Handle **handle1,
 430             Handle **handle2)
 431 {
 432   Line *line;
 433   Connection *conn;
 434   DiaObject *obj;
 435   Point defaultlen = { 1.0, 1.0 };
 436
 437   line_init_defaults();
 438
 439   line = g_malloc0(sizeof(Line));
 440
 441   line->line_width = attributes_get_default_linewidth();
 442   line->line_color = attributes_get_foreground();
 443   line->absolute_start_gap = default_properties.absolute_start_gap;
 444   line->absolute_end_gap = default_properties.absolute_end_gap;
 445
 446   conn = &line->connection;
 447   conn->endpoints[0] = *startpoint;
 448   conn->endpoints[1] = *startpoint;
 449   point_add(&conn->endpoints[1], &defaultlen);
 450
 451   obj = &conn->object;
 452
 453   obj->type = &line_type;
 454   obj->ops = &line_ops;
 455
 456   connection_init(conn, 2, 0);
 457
 458   line->cpl = connpointline_create(obj,1);
 459
 460   attributes_get_default_line_style(&line->line_style, &line->dashlength);
 461   line->start_arrow = attributes_get_default_start_arrow();
 462   line->end_arrow = attributes_get_default_end_arrow();
 463   line_update_data(line);
 464
 465   *handle1 = obj->handles[0];
 466   *handle2 = obj->handles[1];
 467   return &line->connection.object;
 468 }
 469
 470 static void
 471 line_destroy(Line *line)
 472 {
 473   connection_destroy(&line->connection);
 474 }
 475
 476 static DiaObject *
 477 line_copy(Line *line)
 478 {
 479   Line *newline;
 480   Connection *conn, *newconn;
 481   DiaObject *newobj;
 482   int rcc = 0;
 483
 484   conn = &line->connection;
 485
 486   newline = g_malloc0(sizeof(Line));
 487   newconn = &newline->connection;
 488   newobj = &newconn->object;
 489
 490   connection_copy(conn, newconn);
 491
 492   newline->cpl = connpointline_copy(newobj,line->cpl,&rcc);
 493
 494   newline->line_color = line->line_color;
 495   newline->line_width = line->line_width;
 496   newline->line_style = line->line_style;
 497   newline->dashlength = line->dashlength;
 498   newline->start_arrow = line->start_arrow;
 499   newline->end_arrow = line->end_arrow;
 500   newline->absolute_start_gap = line->absolute_start_gap;
 501   newline->absolute_end_gap = line->absolute_end_gap;
 502
 503   line_update_data(line);
 504
 505   return &newline->connection.object;
 506 }
 507
 508 static void
 509 line_update_data(Line *line)
 510 {
 511   Connection *conn = &line->connection;
 512   DiaObject *obj = &conn->object;
 513   LineBBExtras *extra = &conn->extra_spacing;
 514   Point start, end;
 515
 516   extra->start_trans = (line->line_width / 2.0);
 517   extra->end_trans   = (line->line_width / 2.0);
 518   extra->start_long  = (line->line_width / 2.0);
 519   extra->end_long    = (line->line_width / 2.0);
 520   if (line->start_arrow.type != ARROW_NONE)
 521     extra->start_trans = MAX(extra->start_trans,line->start_arrow.width);
 522   if (line->end_arrow.type != ARROW_NONE)
 523     extra->end_trans = MAX(extra->end_trans,line->end_arrow.width);
 524
 525   if (connpoint_is_autogap(line->connection.endpoint_handles[0].connected_to) ||
 526       connpoint_is_autogap(line->connection.endpoint_handles[1].connected_to)) {
 527     connection_adjust_for_autogap(line);
 528   }
 529   if (line->absolute_start_gap || line->absolute_end_gap ) {
 530     Point gap_endpoints[2];
 531
 532     line_adjust_for_absolute_gap(line, gap_endpoints);
 533     line_bbox(&gap_endpoints[0],&gap_endpoints[1],
 534               &conn->extra_spacing,&conn->object.bounding_box);
 535     start = gap_endpoints[0];
 536     end = gap_endpoints[1];
 537   } else {
 538     connection_update_boundingbox(conn);
 539     start = conn->endpoints[0];
 540     end = conn->endpoints[1];
 541   }
 542
 543   obj->position = conn->endpoints[0];
 544
 545   connpointline_update(line->cpl);
 546   connpointline_putonaline(line->cpl,&start, &end);
 547
 548   connection_update_handles(conn);
 549 }
 550
 551
 552 static void
 553 line_save(Line *line, ObjectNode obj_node, const char *filename)
 554 {
 555   dia_object_sanity_check((DiaObject*)line, "Saving line");
 556
 557   connection_save(&line->connection, obj_node);
 558
 559   connpointline_save(line->cpl,obj_node,"numcp");
 560
 561   if (!color_equals(&line->line_color, &color_black))
 562     data_add_color(new_attribute(obj_node, "line_color"),
 563                    &line->line_color);
 564
 565   if (line->line_width != 0.1)
 566     data_add_real(new_attribute(obj_node, "line_width"),
 567                   line->line_width);
 568
 569   if (line->line_style != LINESTYLE_SOLID)
 570     data_add_enum(new_attribute(obj_node, "line_style"),
 571                   line->line_style);
 572
 573   if (line->start_arrow.type != ARROW_NONE) {
 574     save_arrow(obj_node, &line->start_arrow,
 575                "start_arrow", "start_arrow_length", "startend_arrow_width");
 576   }
 577
 578   if (line->end_arrow.type != ARROW_NONE) {
 579     save_arrow(obj_node, &line->end_arrow,
 580                "end_arrow", "end_arrow_length", "end_arrow_width");
 581   }
 582
 583   if (line->absolute_start_gap)
 584     data_add_real(new_attribute(obj_node, "absolute_start_gap"),
 585                  line->absolute_start_gap);
 586   if (line->absolute_end_gap)
 587     data_add_real(new_attribute(obj_node, "absolute_end_gap"),
 588                  line->absolute_end_gap);
 589
 590   if (line->line_style != LINESTYLE_SOLID && line->dashlength != DEFAULT_LINESTYLE_DASHLEN)
 591     data_add_real(new_attribute(obj_node, "dashlength"),
 592                   line->dashlength);
 593 }
 594
 595 static DiaObject *
 596 line_load(ObjectNode obj_node, int version, const char *filename)
 597 {
 598   Line *line;
 599   Connection *conn;
 600   DiaObject *obj;
 601   AttributeNode attr;
 602
 603   line = g_malloc0(sizeof(Line));
 604
 605   conn = &line->connection;
 606   obj = &conn->object;
 607
 608   obj->type = &line_type;
 609   obj->ops = &line_ops;
 610
 611   connection_load(conn, obj_node);
 612
 613   line->line_color = color_black;
 614   attr = object_find_attribute(obj_node, "line_color");
 615   if (attr != NULL)
 616     data_color(attribute_first_data(attr), &line->line_color);
 617
 618   line->line_width = 0.1;
 619   attr = object_find_attribute(obj_node, "line_width");
 620   if (attr != NULL)
 621     line->line_width = data_real(attribute_first_data(attr));
 622
 623   line->line_style = LINESTYLE_SOLID;
 624   attr = object_find_attribute(obj_node, "line_style");
 625   if (attr != NULL)
 626     line->line_style = data_enum(attribute_first_data(attr));
 627
 628   load_arrow(obj_node, &line->start_arrow,
 629              "start_arrow", "start_arrow_length", "start_arrow_width");
 630
 631   load_arrow(obj_node, &line->end_arrow,
 632              "end_arrow", "end_arrow_length", "end_arrow_width");
 633
 634   line->absolute_start_gap = 0.0;
 635   attr = object_find_attribute(obj_node, "absolute_start_gap");
 636   if (attr != NULL)
 637     line->absolute_start_gap =  data_real( attribute_first_data(attr) );
 638   line->absolute_end_gap = 0.0;
 639   attr = object_find_attribute(obj_node, "absolute_end_gap");
 640   if (attr != NULL)
 641     line->absolute_end_gap =  data_real( attribute_first_data(attr) );
 642
 643   line->dashlength = DEFAULT_LINESTYLE_DASHLEN;
 644   attr = object_find_attribute(obj_node, "dashlength");
 645   if (attr != NULL)
 646     line->dashlength = data_real(attribute_first_data(attr));
 647
 648   connection_init(conn, 2, 0);
 649
 650   line->cpl = connpointline_load(obj,obj_node,"numcp",1,NULL);
 651   line_update_data(line);
 652
 653   return &line->connection.object;
 654 }