synfig-core/trunk/src/synfig/valuenode_bline.cpp

   1 /* === S Y N F I G ========================================================= */
   2 /*!     \file valuenode_bline.cpp
   3 **      \brief Template File
   4 **
   5 **      $Id$
   6 **
   7 **      \legal
   8 **      Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
   9 **
  10 **      This package is free software; you can redistribute it and/or
  11 **      modify it under the terms of the GNU General Public License as
  12 **      published by the Free Software Foundation; either version 2 of
  13 **      the License, or (at your option) any later version.
  14 **
  15 **      This package is distributed in the hope that it will be useful,
  16 **      but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 **      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18 **      General Public License for more details.
  19 **      \endlegal
  20 */
  21 /* ========================================================================= */
  22
  23 /* === H E A D E R S ======================================================= */
  24
  25 #ifdef USING_PCH
  26 #       include "pch.h"
  27 #else
  28 #ifdef HAVE_CONFIG_H
  29 #       include <config.h>
  30 #endif
  31
  32 #include "valuenode_bline.h"
  33 #include "valuenode_const.h"
  34 #include "valuenode_composite.h"
  35 #include "general.h"
  36 #include "exception.h"
  37 #include "blinepoint.h"
  38 #include <vector>
  39 #include <list>
  40 #include <algorithm>
  41 #include <ETL/hermite>
  42 #include <ETL/calculus>
  43 #include "segment.h"
  44
  45 #endif
  46
  47 /* === U S I N G =========================================================== */
  48
  49 using namespace std;
  50 using namespace etl;
  51 using namespace synfig;
  52
  53 /* === M A C R O S ========================================================= */
  54
  55 /* === G L O B A L S ======================================================= */
  56
  57 /* === P R O C E D U R E S ================================================= */
  58
  59 inline float
  60 linear_interpolation(const float& a, const float& b, float c)
  61 { return (b-a)*c+a; }
  62
  63 inline Vector
  64 linear_interpolation(const Vector& a, const Vector& b, float c)
  65 { return (b-a)*c+a; }
  66
  67 inline Vector
  68 radial_interpolation(const Vector& a, const Vector& b, float c)
  69 {
  70         // if either extreme is zero then use linear interpolation instead
  71         if (a.is_equal_to(Vector::zero()) || b.is_equal_to(Vector::zero()))
  72                 return linear_interpolation(a, b, c);
  73
  74         affine_combo<Real,float> mag_combo;
  75         affine_combo<Angle,float> ang_combo;
  76
  77         Real mag(mag_combo(a.mag(),b.mag(),c));
  78         Angle ang(ang_combo(Angle::tan(a[1],a[0]),Angle::tan(b[1],b[0]),c));
  79
  80         return Point( mag*Angle::cos(ang).get(),mag*Angle::sin(ang).get() );
  81 }
  82
  83 inline void
  84 transform(Vector in, Vector& out, Point& coord_origin, Point *coord_sys)
  85 {
  86         in -= coord_origin;
  87         out[0] = in * coord_sys[0];
  88         out[1] = in * coord_sys[1];
  89 }
  90
  91 inline void
  92 untransform(const Vector& in, Vector& out, Point& coord_origin, Point *coord_sys)
  93 {
  94         out[0] = in * coord_sys[0];
  95         out[1] = in * coord_sys[1];
  96         out += coord_origin;
  97 }
  98
  99 ValueBase
 100 synfig::convert_bline_to_segment_list(const ValueBase& bline)
 101 {
 102         std::vector<Segment> ret;
 103
 104 //      std::vector<BLinePoint> list(bline.operator std::vector<BLinePoint>());
 105         //std::vector<BLinePoint> list(bline);
 106         std::vector<BLinePoint> list(bline.get_list().begin(),bline.get_list().end());
 107         std::vector<BLinePoint>::const_iterator iter;
 108
 109         BLinePoint prev,first;
 110
 111         //start with prev = first and iter on the second...
 112
 113         if(list.empty()) return ValueBase(ret,bline.get_loop());
 114         first = prev = list.front();
 115
 116         for(iter=++list.begin();iter!=list.end();++iter)
 117         {
 118                 ret.push_back(
 119                         Segment(
 120                                 prev.get_vertex(),
 121                                 prev.get_tangent2(),
 122                                 iter->get_vertex(),
 123                                 iter->get_tangent1()
 124                         )
 125                 );
 126                 prev=*iter;
 127         }
 128         if(bline.get_loop())
 129         {
 130                 ret.push_back(
 131                         Segment(
 132                                 prev.get_vertex(),
 133                                 prev.get_tangent2(),
 134                                 first.get_vertex(),
 135                                 first.get_tangent1()
 136                         )
 137                 );
 138         }
 139         return ValueBase(ret,bline.get_loop());
 140 }
 141
 142 ValueBase
 143 synfig::convert_bline_to_width_list(const ValueBase& bline)
 144 {
 145         std::vector<Real> ret;
 146 //      std::vector<BLinePoint> list(bline.operator std::vector<BLinePoint>());
 147         //std::vector<BLinePoint> list(bline);
 148         std::vector<BLinePoint> list(bline.get_list().begin(),bline.get_list().end());
 149         std::vector<BLinePoint>::const_iterator iter;
 150
 151         if(bline.empty())
 152                 return ValueBase(ValueBase::TYPE_LIST);
 153
 154         for(iter=list.begin();iter!=list.end();++iter)
 155                 ret.push_back(iter->get_width());
 156
 157         if(bline.get_loop())
 158                 ret.push_back(list.front().get_width());
 159
 160         return ValueBase(ret,bline.get_loop());
 161 }
 162
 163
 164 /* === M E T H O D S ======================================================= */
 165
 166
 167 ValueNode_BLine::ValueNode_BLine():
 168         ValueNode_DynamicList(ValueBase::TYPE_BLINEPOINT)
 169 {
 170 }
 171
 172 ValueNode_BLine::~ValueNode_BLine()
 173 {
 174 }
 175
 176 ValueNode_BLine*
 177 ValueNode_BLine::create(const ValueBase &value)
 178 {
 179         if(value.get_type()!=ValueBase::TYPE_LIST)
 180                 return 0;
 181
 182         ValueNode_BLine* value_node(new ValueNode_BLine());
 183
 184         if(!value.empty())
 185         {
 186                 switch(value.get_contained_type())
 187                 {
 188                 case ValueBase::TYPE_BLINEPOINT:
 189                 {
 190 //                      std::vector<BLinePoint> bline_points(value.operator std::vector<BLinePoint>());
 191                         //std::vector<BLinePoint> bline_points(value);
 192                         std::vector<BLinePoint> bline_points(value.get_list().begin(),value.get_list().end());
 193                         std::vector<BLinePoint>::const_iterator iter;
 194
 195                         for(iter=bline_points.begin();iter!=bline_points.end();iter++)
 196                         {
 197                                 value_node->add(ValueNode::Handle(ValueNode_Composite::create(*iter)));
 198                         }
 199                         value_node->set_loop(value.get_loop());
 200                 }
 201                         break;
 202                 case ValueBase::TYPE_SEGMENT:
 203                 {
 204                         // Here, we want to convert a list of segments
 205                         // into a list of BLinePoints. We make an assumption
 206                         // that the segment list is continuous(sp), but not necessarily
 207                         // smooth.
 208
 209                         value_node->set_loop(false);
 210 //                      std::vector<Segment> segments(value.operator std::vector<Segment>());
 211 //                      std::vector<Segment> segments(value);
 212                         std::vector<Segment> segments(value.get_list().begin(),value.get_list().end());
 213                         std::vector<Segment>::const_iterator iter,last(segments.end());
 214                         --last;
 215                         ValueNode_Const::Handle prev,first;
 216
 217                         for(iter=segments.begin();iter!=segments.end();iter++)
 218                         {
 219 #define PREV_POINT      prev->get_value().get(BLinePoint())
 220 #define FIRST_POINT     first->get_value().get(BLinePoint())
 221 #define CURR_POINT      curr->get_value().get(BLinePoint())
 222                                 if(iter==segments.begin())
 223                                 {
 224                                         prev=ValueNode_Const::create(ValueBase::TYPE_BLINEPOINT);
 225                                         {
 226                                                 BLinePoint prev_point(PREV_POINT);
 227                                                 prev_point.set_vertex(iter->p1);
 228                                                 prev_point.set_tangent1(iter->t1);
 229                                                 prev_point.set_width(0.01);
 230                                                 prev_point.set_origin(0.5);
 231                                                 prev_point.set_split_tangent_flag(false);
 232                                                 prev->set_value(prev_point);
 233                                         }
 234                                         first=prev;
 235                                         value_node->add(ValueNode::Handle(prev));
 236
 237                                 }
 238                                 if(iter==last && iter->p2.is_equal_to(FIRST_POINT.get_vertex()))
 239                                 {
 240                                         value_node->set_loop(true);
 241                                         if(!iter->t2.is_equal_to(FIRST_POINT.get_tangent1()))
 242                                         {
 243                                                 BLinePoint first_point(FIRST_POINT);
 244                                                 first_point.set_tangent1(iter->t2);
 245                                                 first->set_value(first_point);
 246                                         }
 247                                         continue;
 248                                 }
 249
 250                                 ValueNode_Const::Handle curr;
 251                                 curr=ValueNode_Const::create(ValueBase::TYPE_BLINEPOINT);
 252                                 {
 253                                         BLinePoint curr_point(CURR_POINT);
 254                                         curr_point.set_vertex(iter->p2);
 255                                         curr_point.set_tangent1(iter->t2);
 256                                         curr_point.set_width(0.01);
 257                                         curr_point.set_origin(0.5);
 258                                         curr_point.set_split_tangent_flag(false);
 259                                         curr->set_value(curr_point);
 260                                 }
 261                                 if(!PREV_POINT.get_tangent1().is_equal_to(iter->t1))
 262                                 {
 263                                         BLinePoint prev_point(PREV_POINT);
 264                                         prev_point.set_split_tangent_flag(true);
 265                                         prev_point.set_tangent2(iter->t1);
 266                                         prev->set_value(prev_point);
 267                                 }
 268                                 value_node->add(ValueNode::Handle(curr));
 269                                 prev=curr;
 270                         }
 271
 272                 }
 273                         break;
 274                 default:
 275                         // We got a list of who-knows-what. We don't have any idea
 276                         // what to do with it.
 277                         return 0;
 278                         break;
 279                 }
 280         }
 281
 282
 283         return value_node;
 284 }
 285
 286 ValueNode_BLine::ListEntry
 287 ValueNode_BLine::create_list_entry(int index, Time time, Real origin)
 288 {
 289         ValueNode_BLine::ListEntry ret;
 290
 291
 292         synfig::BLinePoint prev,next;
 293
 294         int prev_i,next_i;
 295
 296         index=index%link_count();
 297
 298         assert(index>=0);
 299         ret.index=index;
 300         ret.set_parent_value_node(this);
 301
 302         if(!list[index].status_at_time(time))
 303                 next_i=find_next_valid_entry(index,time);
 304         else
 305                 next_i=index;
 306         prev_i=find_prev_valid_entry(index,time);
 307
 308         synfig::info("index=%d, next_i=%d, prev_i=%d",index,next_i,prev_i);
 309
 310         next=(*list[next_i].value_node)(time);
 311         prev=(*list[prev_i].value_node)(time);
 312
 313         etl::hermite<Vector> curve(prev.get_vertex(),next.get_vertex(),prev.get_tangent2(),next.get_tangent1());
 314         etl::derivative< etl::hermite<Vector> > deriv(curve);
 315
 316         synfig::BLinePoint bline_point;
 317         bline_point.set_vertex(curve(origin));
 318         bline_point.set_width((next.get_width()-prev.get_width())*origin+prev.get_width());
 319         bline_point.set_tangent1(deriv(origin)*min(1.0-origin,origin));
 320         bline_point.set_tangent2(bline_point.get_tangent1());
 321         bline_point.set_split_tangent_flag(false);
 322         bline_point.set_origin(origin);
 323
 324         ret.value_node=ValueNode_Composite::create(bline_point);
 325
 326         return ret;
 327 }
 328
 329 ValueBase
 330 ValueNode_BLine::operator()(Time t)const
 331 {
 332         std::vector<BLinePoint> ret_list;
 333
 334         std::vector<ListEntry>::const_iterator iter,first_iter;
 335         bool first_flag(true);
 336         bool rising;
 337         int index(0);
 338         float next_scale(1.0f);
 339
 340         BLinePoint prev,first;
 341         first.set_origin(100.0f);
 342
 343         for(iter=list.begin();iter!=list.end();++iter,index++)
 344         {
 345                 float amount(iter->amount_at_time(t,&rising));
 346
 347                 assert(amount>=0.0f);
 348                 assert(amount<=1.0f);
 349
 350                 if(amount==1.0f)
 351                 {
 352                         if(first_flag)
 353                         {
 354                                 first_iter=iter;
 355                                 first=prev=(*iter->value_node)(t).get(prev);
 356                                 first_flag=false;
 357                                 ret_list.push_back(first);
 358                                 continue;
 359                         }
 360
 361                         BLinePoint curr;
 362                         curr=(*iter->value_node)(t).get(prev);
 363
 364                         if(next_scale!=1.0f)
 365                         {
 366                                 ret_list.back().set_split_tangent_flag(true);
 367                                 ret_list.back().set_tangent2(prev.get_tangent2()*next_scale);
 368
 369                                 ret_list.push_back(curr);
 370
 371                                 ret_list.back().set_split_tangent_flag(true);
 372                                 ret_list.back().set_tangent2(curr.get_tangent2());
 373                                 ret_list.back().set_tangent1(curr.get_tangent1()*next_scale);
 374
 375                                 next_scale=1.0f;
 376                         }
 377                         else
 378                         {
 379                                 ret_list.push_back(curr);
 380                         }
 381
 382                         prev=curr;
 383                 }
 384                 else
 385                 if(amount>0.0f)
 386                 {
 387                         std::vector<ListEntry>::const_iterator begin_iter,end_iter;
 388
 389                         // This is where the interesting stuff happens
 390                         // We need to seek forward in the list to see what the next
 391                         // active point is
 392
 393                         BLinePoint blp_here_on;  // the current vertex, when fully on
 394                         BLinePoint blp_here_off; // the current vertex, when fully off
 395                         BLinePoint blp_here_now; // the current vertex, right now (between on and off)
 396                         BLinePoint blp_prev_off; // the beginning of dynamic group when fully off
 397                         BLinePoint blp_next_off; // end of the dynamic group when fully off
 398
 399                         int dist_from_begin(0), dist_from_end(0);
 400                         Time off_time, on_time;
 401
 402                         if(!rising)
 403                         {
 404                                 try{ on_time=iter->find_prev(t)->get_time(); }
 405                                 catch(...) { on_time=Time::begin(); }
 406                                 try{ off_time=iter->find_next(t)->get_time(); }
 407                                 catch(...) { off_time=Time::end(); }
 408                         }
 409                         else
 410                         {
 411                                 try{ off_time=iter->find_prev(t)->get_time(); }
 412                                 catch(...) { off_time=Time::begin(); }
 413                                 try{ on_time=iter->find_next(t)->get_time(); }
 414                                 catch(...) { on_time=Time::end(); }
 415                         }
 416
 417                         blp_here_on=(*iter->value_node)(on_time).get(blp_here_on);
 418 //                      blp_here_on=(*iter->value_node)(t).get(blp_here_on);
 419
 420                         // Find "end" of dynamic group
 421                         end_iter=iter;
 422 //                      for(++end_iter;begin_iter!=list.end();++end_iter)
 423                         for(++end_iter;end_iter!=list.end();++end_iter)
 424                                 if(end_iter->amount_at_time(t)>amount)
 425                                 {
 426                                         blp_next_off=(*end_iter->value_node)(off_time).get(prev);
 427                                         break;
 428                                 }
 429
 430                         // If we did not find an end of the dynamic group...
 431                         if(end_iter==list.end())
 432                         {
 433                                 if(get_loop())
 434                                 {
 435                                         end_iter=first_iter;
 436                                         blp_next_off=(*end_iter->value_node)(off_time).get(prev);
 437 //                                      end=first;
 438                                 }
 439                                 else
 440                                 {
 441                                         // Writeme!
 442                                         end_iter=first_iter;
 443                                         blp_next_off=(*end_iter->value_node)(off_time).get(prev);
 444 //                                      end=first;
 445                                 }
 446                         }
 447
 448                         // Find "begin" of dynamic group
 449                         begin_iter=iter;
 450                         blp_prev_off.set_origin(100.0f); // set the origin to 100 (which is crazy) so that we can check to see if it was found
 451                         do
 452                         {
 453                                 if(begin_iter==list.begin())
 454                                 {
 455                                         if(get_loop())
 456                                                 begin_iter=list.end();
 457                                         else
 458                                                 break;
 459                                 }
 460
 461                                 --begin_iter;
 462                                 dist_from_begin++;
 463
 464                                 if(begin_iter==iter)
 465                                         break;
 466
 467                                 if(begin_iter->amount_at_time(t)>amount)
 468                                 {
 469                                         blp_prev_off=(*begin_iter->value_node)(off_time).get(prev);
 470                                         break;
 471                                 }
 472                         }while(begin_iter!=iter);
 473
 474                         // If we did not find a begin
 475                         if(blp_prev_off.get_origin()==100.0f)
 476                         {
 477                                 if(get_loop())
 478                                 {
 479                                         begin_iter=first_iter;
 480                                         blp_prev_off=(*begin_iter->value_node)(off_time).get(prev);
 481 //                                      blp_prev_off=first;
 482                                 }
 483                                 else
 484                                 {
 485                                         // Writeme!
 486                                         begin_iter=first_iter;
 487                                         blp_prev_off=(*begin_iter->value_node)(off_time).get(prev);
 488 //                                      blp_prev_off=first;
 489                                 }
 490                         }
 491
 492                         etl::hermite<Vector> curve(blp_prev_off.get_vertex(),   blp_next_off.get_vertex(),
 493                                                                            blp_prev_off.get_tangent2(), blp_next_off.get_tangent1());
 494                         etl::derivative< etl::hermite<Vector> > deriv(curve);
 495
 496                         blp_here_off.set_vertex(curve(blp_here_on.get_origin()));
 497
 498                         blp_here_off.set_width((blp_next_off.get_width()-blp_prev_off.get_width())*blp_here_on.get_origin()+blp_prev_off.get_width());
 499
 500                         blp_here_off.set_tangent1(deriv(blp_here_on.get_origin()));
 501                         blp_here_off.set_tangent2(deriv(blp_here_on.get_origin()));
 502
 503                         float prev_tangent_scalar(1.0f);
 504                         float next_tangent_scalar(1.0f);
 505
 506                         //synfig::info("index_%d:dist_from_begin=%d",index,dist_from_begin);
 507                         //synfig::info("index_%d:dist_from_end=%d",index,dist_from_end);
 508
 509                         // If we are the next to the begin
 510                         if(begin_iter==--std::vector<ListEntry>::const_iterator(iter) || dist_from_begin==1)
 511                                 prev_tangent_scalar=linear_interpolation(blp_here_on.get_origin(), 1.0f, amount);
 512                         else
 513                                 prev_tangent_scalar=linear_interpolation(blp_here_on.get_origin()-prev.get_origin(), 1.0f, amount);
 514
 515                         // If we are the next to the end
 516                         if(end_iter==++std::vector<ListEntry>::const_iterator(iter) || dist_from_end==1)
 517                                 next_tangent_scalar=linear_interpolation(1.0-blp_here_on.get_origin(), 1.0f, amount);
 518                         else if(list.end()!=++std::vector<ListEntry>::const_iterator(iter))
 519                         {
 520                                 BLinePoint next;
 521                                 next=((*(++std::vector<ListEntry>::const_iterator(iter))->value_node)(t).get(prev));
 522                                 next_tangent_scalar=linear_interpolation(next.get_origin()-blp_here_on.get_origin(), 1.0f, amount);
 523                         }
 524                         else
 525                                 //! \todo this isn't quite right; we should handle looped blines identically no matter where the loop happens
 526                                 //! and we currently don't.  this at least makes it a lot better than it was before
 527                                 next_tangent_scalar=linear_interpolation(blp_next_off.get_origin()-blp_here_on.get_origin(), 1.0f, amount);
 528                         next_scale=next_tangent_scalar;
 529
 530                         //blp_here_now.set_vertex(linear_interpolation(blp_here_off.get_vertex(), blp_here_on.get_vertex(), amount));
 531                         // if(false)
 532                         // {
 533                         //      // My first try
 534                         //      Point ref_point_begin(((*begin_iter->value_node)(off_time).get(prev).get_vertex() +
 535                         //                                                 (*end_iter->value_node)(off_time).get(prev).get_vertex()) * 0.5);
 536                         //      Point ref_point_end(((*begin_iter->value_node)(on_time).get(prev).get_vertex() +
 537                         //                                               (*end_iter->value_node)(on_time).get(prev).get_vertex()) * 0.5);
 538                         //      Point ref_point_now(((*begin_iter->value_node)(t).get(prev).get_vertex() +
 539                         //                                               (*end_iter->value_node)(t).get(prev).get_vertex()) * 0.5);
 540                         //      Point ref_point_linear(linear_interpolation(ref_point_begin, ref_point_end, amount));
 541                         //
 542                         //      blp_here_now.set_vertex(linear_interpolation(blp_here_off.get_vertex(), blp_here_on.get_vertex(), amount) +
 543                         //                                                      (ref_point_now-ref_point_linear));
 544                         //      blp_here_now.set_tangent1(linear_interpolation(blp_here_off.get_tangent1(), blp_here_on.get_tangent1(), amount));
 545                         //      blp_here_now.set_split_tangent_flag(blp_here_on.get_split_tangent_flag());
 546                         //      if(blp_here_now.get_split_tangent_flag())
 547                         //              blp_here_now.set_tangent2(linear_interpolation(blp_here_off.get_tangent2(), blp_here_on.get_tangent2(), amount));
 548                         // }
 549                         // else
 550                         {
 551                                 // My second try
 552
 553                                 // define 3 coordinate systems:
 554                                 Point off_coord_sys[2],   off_coord_origin; // when the current vertex is completely off
 555                                 Point on_coord_sys[2] ,    on_coord_origin; // when the current vertex is completely on
 556                                 Point curr_coord_sys[2], curr_coord_origin; // the current state - somewhere in between
 557
 558                                 // for each of the 3 systems, the origin is half way between the previous and next active point
 559                                 // and the axes are based on a vector from the next active point to the previous
 560                                 {
 561                                         const Point   end_pos_at_off_time((  *end_iter->value_node)(off_time).get(prev).get_vertex());
 562                                         const Point begin_pos_at_off_time((*begin_iter->value_node)(off_time).get(prev).get_vertex());
 563                                         off_coord_origin=(begin_pos_at_off_time + end_pos_at_off_time)/2;
 564                                         off_coord_sys[0]=(begin_pos_at_off_time - end_pos_at_off_time).norm();
 565                                         off_coord_sys[1]=off_coord_sys[0].perp();
 566
 567                                         const Point   end_pos_at_on_time((  *end_iter->value_node)(on_time).get(prev).get_vertex());
 568                                         const Point begin_pos_at_on_time((*begin_iter->value_node)(on_time).get(prev).get_vertex());
 569                                         on_coord_origin=(begin_pos_at_on_time + end_pos_at_on_time)/2;
 570                                         on_coord_sys[0]=(begin_pos_at_on_time - end_pos_at_on_time).norm();
 571                                         on_coord_sys[1]=on_coord_sys[0].perp();
 572
 573                                         const Point   end_pos_at_current_time((  *end_iter->value_node)(t).get(prev).get_vertex());
 574                                         const Point begin_pos_at_current_time((*begin_iter->value_node)(t).get(prev).get_vertex());
 575                                         curr_coord_origin=(begin_pos_at_current_time + end_pos_at_current_time)/2;
 576                                         curr_coord_sys[0]=(begin_pos_at_current_time - end_pos_at_current_time).norm();
 577                                         curr_coord_sys[1]=curr_coord_sys[0].perp();
 578                                 }
 579
 580                                 /* The code that was here before used just end_iter as the origin, rather than the mid-point */
 581
 582                                 // For each of the 3 coordinate systems we've just defined, we convert a point and tangent(s) into that system
 583                                 Point trans_on_point, trans_off_point, untrans_curr_point;
 584                                 Vector trans_on_t1, trans_on_t2, trans_off_t1, trans_off_t2, untrans_curr_t1, untrans_curr_t2;
 585
 586                                 // Convert points where vertex is fully on and fully off
 587                                 transform(blp_here_on.get_vertex(),  trans_on_point,  on_coord_origin,  on_coord_sys);
 588                                 transform(blp_here_off.get_vertex(), trans_off_point, off_coord_origin, off_coord_sys);
 589
 590 #define COORD_SYS_RADIAL_TAN_INTERP 1
 591
 592 #ifdef COORD_SYS_RADIAL_TAN_INTERP
 593                                 // this I don't understand.  why add on this bit ---v
 594                                 transform(blp_here_on.get_tangent1()  + blp_here_on.get_vertex(),  trans_on_t1,  on_coord_origin,  on_coord_sys);
 595                                 transform(blp_here_off.get_tangent1() + blp_here_off.get_vertex(), trans_off_t1, off_coord_origin, off_coord_sys);
 596
 597                                 if(blp_here_on.get_split_tangent_flag())
 598                                 {
 599                                         transform(blp_here_on.get_tangent2()+blp_here_on.get_vertex(),   trans_on_t2,  on_coord_origin,  on_coord_sys);
 600                                         transform(blp_here_off.get_tangent2()+blp_here_off.get_vertex(), trans_off_t2, off_coord_origin, off_coord_sys);
 601                                 }
 602 #endif
 603                                 // Convert current point
 604                                 // Transpose (invert)
 605                                 swap(curr_coord_sys[0][1],curr_coord_sys[1][0]);
 606
 607                                 // interpolate between the 'on' point and the 'off' point and untransform to get our point's location
 608                                 untransform(linear_interpolation(trans_off_point, trans_on_point, amount),
 609                                                         untrans_curr_point, curr_coord_origin, curr_coord_sys);
 610
 611 #define INTERP_FUNCTION         radial_interpolation
 612 //#define INTERP_FUNCTION       linear_interpolation
 613
 614 #ifdef COORD_SYS_RADIAL_TAN_INTERP
 615                                 untransform(INTERP_FUNCTION(trans_off_t1,trans_on_t1,amount),
 616                                                         untrans_curr_t1, curr_coord_origin, curr_coord_sys);
 617                                 untrans_curr_t1 -= untrans_curr_point;
 618
 619                                 if(blp_here_on.get_split_tangent_flag())
 620                                 {
 621                                         untransform(INTERP_FUNCTION(trans_off_t2,trans_on_t2,amount),
 622                                                                 untrans_curr_t2, curr_coord_origin, curr_coord_sys);
 623                                         untrans_curr_t2 -= untrans_curr_point;
 624                                 }
 625 #endif
 626
 627                                 blp_here_now.set_vertex(untrans_curr_point);
 628 #ifndef COORD_SYS_RADIAL_TAN_INTERP
 629                                 blp_here_now.set_tangent1(radial_interpolation(blp_here_off.get_tangent1(),blp_here_on.get_tangent1(),amount));
 630                                 blp_here_now.set_split_tangent_flag(blp_here_on.get_split_tangent_flag());
 631                                 if(blp_here_now.get_split_tangent_flag())
 632                                         blp_here_now.set_tangent2(radial_interpolation(blp_here_off.get_tangent2(),blp_here_on.get_tangent2(),amount));
 633 #else
 634                                 blp_here_now.set_tangent1(untrans_curr_t1);
 635                                 blp_here_now.set_split_tangent_flag(blp_here_on.get_split_tangent_flag());
 636                                 if(blp_here_now.get_split_tangent_flag())
 637                                         blp_here_now.set_tangent2(untrans_curr_t2);
 638 #endif
 639                         }
 640
 641                         blp_here_now.set_origin(blp_here_on.get_origin());
 642                         blp_here_now.set_width(linear_interpolation(blp_here_off.get_width(), blp_here_on.get_width(), amount));
 643
 644
 645                         // Handle the case where we are the first vertex
 646                         if(first_flag)
 647                         {
 648                                 blp_here_now.set_tangent1(blp_here_now.get_tangent1()*prev_tangent_scalar);
 649                                 first_iter=iter;
 650                                 first=prev=blp_here_now;
 651                                 first_flag=false;
 652                                 ret_list.push_back(blp_here_now);
 653                                 continue;
 654                         }
 655
 656                         ret_list.back().set_split_tangent_flag(true);
 657                         ret_list.back().set_tangent2(prev.get_tangent2()*prev_tangent_scalar);
 658                         ret_list.push_back(blp_here_now);
 659                         ret_list.back().set_split_tangent_flag(true);
 660                         //ret_list.back().set_tangent2(blp_here_now.get_tangent1());
 661                         ret_list.back().set_tangent1(blp_here_now.get_tangent1()*prev_tangent_scalar);
 662
 663                         prev=blp_here_now;
 664                 }
 665         }
 666
 667         if(next_scale!=1.0f)
 668         {
 669                 ret_list.back().set_split_tangent_flag(true);
 670                 ret_list.back().set_tangent2(prev.get_tangent2()*next_scale);
 671         }
 672
 673 /*
 674         if(get_loop() && !first_flag)
 675         {
 676                 ret_list.push_back(
 677                         Segment(
 678                         prev.get_vertex(),
 679                         prev.get_tangent2(),
 680                         first.get_vertex(),
 681                         first.get_tangent1()
 682                         )
 683                 );
 684         }
 685 */
 686
 687         if(list.empty())
 688                 synfig::warning(string("ValueNode_BLine::operator()():")+_("No entries in list"));
 689         else
 690         if(ret_list.empty())
 691                 synfig::warning(string("ValueNode_BLine::operator()():")+_("No entries in ret_list"));
 692
 693         return ValueBase(ret_list,get_loop());
 694 }
 695
 696 String
 697 ValueNode_BLine::link_local_name(int i)const
 698 {
 699         assert(i>=0 && (unsigned)i<list.size());
 700         return etl::strprintf(_("Vertex %03d"),i+1);
 701 }
 702
 703 ValueNode*
 704 ValueNode_BLine::clone(const GUID& deriv_guid)const
 705 {
 706         { ValueNode* x(find_value_node(get_guid()^deriv_guid).get()); if(x)return x; }
 707
 708         ValueNode_BLine* ret=new ValueNode_BLine();
 709         ret->set_guid(get_guid()^deriv_guid);
 710
 711         std::vector<ListEntry>::const_iterator iter;
 712
 713         for(iter=list.begin();iter!=list.end();++iter)
 714         {
 715                 if(iter->value_node->is_exported())
 716                         ret->add(*iter);
 717                 else
 718                 {
 719                         ListEntry list_entry(*iter);
 720                         //list_entry.value_node=find_value_node(iter->value_node->get_guid()^deriv_guid).get();
 721                         //if(!list_entry.value_node)
 722                                 list_entry.value_node=iter->value_node->clone(deriv_guid);
 723                         ret->add(list_entry);
 724                         //ret->list.back().value_node=iter->value_node.clone();
 725                 }
 726         }
 727         ret->set_loop(get_loop());
 728
 729         return ret;
 730 }
 731
 732 String
 733 ValueNode_BLine::get_name()const
 734 {
 735         return "bline";
 736 }
 737
 738 String
 739 ValueNode_BLine::get_local_name()const
 740 {
 741         return _("BLine");
 742 }
 743
 744 LinkableValueNode*
 745 ValueNode_BLine::create_new()const
 746 {
 747         assert(0);
 748         return 0;
 749 }
 750
 751 bool
 752 ValueNode_BLine::check_type(ValueBase::Type type)
 753 {
 754         return type==ValueBase::TYPE_LIST;
 755 }