synfig-core/src/modules/lyr_std/curvewarp.cpp

   1 /* === S Y N F I G ========================================================= */
   2 /*!     \file curvewarp.cpp
   3 **      \brief Implementation of the "Curve Warp" layer
   4 **
   5 **      $Id$
   6 **
   7 **      \legal
   8 **      Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
   9 **      Copyright (c) 2007-2008 Chris Moore
  10 **
  11 **      This package is free software; you can redistribute it and/or
  12 **      modify it under the terms of the GNU General Public License as
  13 **      published by the Free Software Foundation; either version 2 of
  14 **      the License, or (at your option) any later version.
  15 **
  16 **      This package is distributed in the hope that it will be useful,
  17 **      but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 **      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  19 **      General Public License for more details.
  20 **      \endlegal
  21 **
  22 ** === N O T E S ===========================================================
  23 **
  24 ** ========================================================================= */
  25
  26 /* === H E A D E R S ======================================================= */
  27
  28 #ifdef USING_PCH
  29 #       include "pch.h"
  30 #else
  31 #ifdef HAVE_CONFIG_H
  32 #       include <config.h>
  33 #endif
  34
  35 #include "curvewarp.h"
  36
  37 #include <synfig/context.h>
  38 #include <synfig/paramdesc.h>
  39 #include <synfig/surface.h>
  40 #include <synfig/valuenode.h>
  41 #include <ETL/calculus>
  42
  43 #endif
  44
  45 /* === M A C R O S ========================================================= */
  46
  47 #define FAKE_TANGENT_STEP 0.000001
  48 #define TOO_THIN 0.01
  49
  50 /* === G L O B A L S ======================================================= */
  51
  52 SYNFIG_LAYER_INIT(CurveWarp);
  53 SYNFIG_LAYER_SET_NAME(CurveWarp,"curve_warp");
  54 SYNFIG_LAYER_SET_LOCAL_NAME(CurveWarp,N_("Curve Warp"));
  55 SYNFIG_LAYER_SET_CATEGORY(CurveWarp,N_("Distortions"));
  56 SYNFIG_LAYER_SET_VERSION(CurveWarp,"0.0");
  57 SYNFIG_LAYER_SET_CVS_ID(CurveWarp,"$Id$");
  58
  59 /* === P R O C E D U R E S ================================================= */
  60
  61 inline float calculate_distance(const std::vector<synfig::BLinePoint>& bline)
  62 {
  63         std::vector<synfig::BLinePoint>::const_iterator iter,next,ret;
  64         std::vector<synfig::BLinePoint>::const_iterator end(bline.end());
  65
  66         float dist(0);
  67
  68         if (bline.empty()) return dist;
  69
  70         next=bline.begin();
  71         iter=next++;
  72
  73         for(;next!=end;iter=next++)
  74         {
  75                 // Setup the curve
  76                 etl::hermite<Vector> curve(iter->get_vertex(), next->get_vertex(), iter->get_tangent2(), next->get_tangent1());
  77                 dist+=curve.length();
  78         }
  79
  80         return dist;
  81 }
  82
  83 std::vector<synfig::BLinePoint>::const_iterator
  84 find_closest_to_bline(bool fast, const std::vector<synfig::BLinePoint>& bline,const Point& p,float& t, float& len, bool& extreme)
  85 {
  86         std::vector<synfig::BLinePoint>::const_iterator iter,next,ret;
  87         std::vector<synfig::BLinePoint>::const_iterator end(bline.end());
  88
  89         ret=bline.end();
  90         float dist(100000000000.0);
  91         next=bline.begin();
  92         float best_pos(0), best_len(0);
  93         etl::hermite<Vector> best_curve;
  94         iter=next++;
  95         Point bp;
  96         float total_len(0);
  97         bool first = true, last = false;
  98         extreme = false;
  99
 100         for(;next!=end;iter=next++)
 101         {
 102                 // Setup the curve
 103                 etl::hermite<Vector> curve(iter->get_vertex(), next->get_vertex(), iter->get_tangent2(), next->get_tangent1());
 104                 float thisdist(0);
 105                 last = false;
 106
 107                 if (fast)
 108                 {
 109 #define POINT_CHECK(x) bp=curve(x);     thisdist=(bp-p).mag_squared(); if(thisdist<dist) { extreme = (first&&x<0.01); ret=iter; best_len = total_len; dist=thisdist; best_curve=curve; last=true; best_pos=x;}
 110                         POINT_CHECK(0.0001);  POINT_CHECK((1.0/6)); POINT_CHECK((2.0/6)); POINT_CHECK((3.0/6));
 111                         POINT_CHECK((4.0/6)); POINT_CHECK((5.0/6)); POINT_CHECK(0.9999);
 112                 }
 113                 else
 114                 {
 115                         float pos = curve.find_closest(fast, p);
 116                         thisdist=(curve(pos)-p).mag_squared();
 117                         if(thisdist<dist)
 118                         {
 119                                 extreme = (first && pos == 0);
 120                                 ret=iter;
 121                                 dist=thisdist;
 122                                 best_pos = pos;
 123                                 best_curve = curve;
 124                                 best_len = total_len;
 125                                 last = true;
 126                         }
 127                 }
 128                 total_len += curve.length();
 129                 first = false;
 130         }
 131
 132         t = best_pos;
 133         if (fast)
 134         {
 135                 len = best_len + best_curve.find_distance(0,best_curve.find_closest(fast, p));
 136                 if (last && t > .99) extreme = true;
 137         }
 138         else
 139         {
 140                 len = best_len + best_curve.find_distance(0,best_pos);
 141                 if (last && t == 1) extreme = true;
 142         }
 143         return ret;
 144 }
 145
 146 /* === M E T H O D S ======================================================= */
 147
 148 inline void
 149 CurveWarp::sync()
 150 {
 151         curve_length_=calculate_distance(bline);
 152         perp_ = (end_point - start_point).perp().norm();
 153 }
 154
 155 CurveWarp::CurveWarp():
 156         origin(0,0),
 157         perp_width(1),
 158         start_point(-2.5,-0.5),
 159         end_point(2.5,-0.3),
 160         fast(true)
 161 {
 162         bline.push_back(BLinePoint());
 163         bline.push_back(BLinePoint());
 164         bline[0].set_vertex(Point(-2.5,0));
 165         bline[1].set_vertex(Point( 2.5,0));
 166         bline[0].set_tangent(Point(1,  0.1));
 167         bline[1].set_tangent(Point(1, -0.1));
 168         bline[0].set_width(1.0f);
 169         bline[1].set_width(1.0f);
 170
 171         sync();
 172 }
 173
 174 inline Point
 175 CurveWarp::transform(const Point &point_, Real *dist, Real *along, int quality)const
 176 {
 177         Vector tangent;
 178         Vector diff;
 179         Point p1;
 180         Real thickness;
 181         bool edge_case = false;
 182         float len(0);
 183         bool extreme;
 184         float t;
 185
 186         if(bline.size()==0)
 187                 return Point();
 188         else if(bline.size()==1)
 189         {
 190                 tangent=bline.front().get_tangent1();
 191                 p1=bline.front().get_vertex();
 192                 thickness=bline.front().get_width();
 193                 t = 0.5;
 194                 extreme = false;
 195         }
 196         else
 197         {
 198                 Point point(point_-origin);
 199
 200                 std::vector<synfig::BLinePoint>::const_iterator iter,next;
 201
 202                 // Figure out the BLinePoint we will be using,
 203                 next=find_closest_to_bline(fast,bline,point,t,len,extreme);
 204
 205                 iter=next++;
 206                 if(next==bline.end()) next=bline.begin();
 207
 208                 // Setup the curve
 209                 etl::hermite<Vector> curve(iter->get_vertex(), next->get_vertex(), iter->get_tangent2(), next->get_tangent1());
 210
 211                 // Setup the derivative function
 212                 etl::derivative<etl::hermite<Vector> > deriv(curve);
 213
 214                 int search_iterations(7);
 215
 216                 if(quality<=6)search_iterations=7;
 217                 else if(quality<=7)search_iterations=6;
 218                 else if(quality<=8)search_iterations=5;
 219                 else search_iterations=4;
 220
 221                 // Figure out the closest point on the curve
 222                 if (fast) t = curve.find_closest(fast, point,search_iterations);
 223
 224                 // Calculate our values
 225                 p1=curve(t);                     // the closest point on the curve
 226                 tangent=deriv(t);                // the tangent at that point
 227
 228                 // if the point we're nearest to is at either end of the
 229                 // bline, our distance from the curve is the distance from the
 230                 // point on the curve.  we need to know which side of the
 231                 // curve we're on, so find the average of the two tangents at
 232                 // this point
 233                 if (t<0.00001 || t>0.99999)
 234                 {
 235                         bool zero_tangent = (tangent[0] == 0 && tangent[1] == 0);
 236
 237                         if (t<0.5)
 238                         {
 239                                 if (iter->get_split_tangent_flag() || zero_tangent)
 240                                 {
 241                                         // fake the current tangent if we need to
 242                                         if (zero_tangent) tangent = curve(FAKE_TANGENT_STEP) - curve(0);
 243
 244                                         // calculate the other tangent
 245                                         Vector other_tangent(iter->get_tangent1());
 246                                         if (other_tangent[0] == 0 && other_tangent[1] == 0)
 247                                         {
 248                                                 // find the previous blinepoint
 249                                                 std::vector<synfig::BLinePoint>::const_iterator prev;
 250                                                 if (iter != bline.begin()) (prev = iter)--;
 251                                                 else prev = iter;
 252
 253                                                 etl::hermite<Vector> other_curve(prev->get_vertex(), iter->get_vertex(), prev->get_tangent2(), iter->get_tangent1());
 254                                                 other_tangent = other_curve(1) - other_curve(1-FAKE_TANGENT_STEP);
 255                                         }
 256
 257                                         // normalise and sum the two tangents
 258                                         tangent=(other_tangent.norm()+tangent.norm());
 259                                         edge_case=true;
 260                                 }
 261                         }
 262                         else
 263                         {
 264                                 if (next->get_split_tangent_flag() || zero_tangent)
 265                                 {
 266                                         // fake the current tangent if we need to
 267                                         if (zero_tangent) tangent = curve(1) - curve(1-FAKE_TANGENT_STEP);
 268
 269                                         // calculate the other tangent
 270                                         Vector other_tangent(next->get_tangent2());
 271                                         if (other_tangent[0] == 0 && other_tangent[1] == 0)
 272                                         {
 273                                                 // find the next blinepoint
 274                                                 std::vector<synfig::BLinePoint>::const_iterator next2(next);
 275                                                 if (++next2 == bline.end())
 276                                                         next2 = next;
 277
 278                                                 etl::hermite<Vector> other_curve(next->get_vertex(), next2->get_vertex(), next->get_tangent2(), next2->get_tangent1());
 279                                                 other_tangent = other_curve(FAKE_TANGENT_STEP) - other_curve(0);
 280                                         }
 281
 282                                         // normalise and sum the two tangents
 283                                         tangent=(other_tangent.norm()+tangent.norm());
 284                                         edge_case=true;
 285                                 }
 286                         }
 287                 }
 288                 tangent = tangent.norm();
 289
 290                 // the width of the bline at the closest point on the curve
 291                 thickness=(next->get_width()-iter->get_width())*t+iter->get_width();
 292         }
 293
 294         if (thickness < TOO_THIN && thickness > -TOO_THIN)
 295         {
 296                 if (thickness > 0) thickness = TOO_THIN;
 297                 else thickness = -TOO_THIN;
 298         }
 299
 300         if (extreme)
 301         {
 302                 Vector tangent;
 303
 304                 if (t < 0.5)
 305                 {
 306                         std::vector<synfig::BLinePoint>::const_iterator iter(bline.begin());
 307                         tangent = iter->get_tangent1().norm();
 308                         len = 0;
 309                 }
 310                 else
 311                 {
 312                         std::vector<synfig::BLinePoint>::const_iterator iter(--bline.end());
 313                         tangent = iter->get_tangent2().norm();
 314                         len = curve_length_;
 315                 }
 316                 len += (point_-origin - p1)*tangent;
 317                 diff = tangent.perp();
 318         }
 319         else if (edge_case)
 320         {
 321                 diff=(p1-(point_-origin));
 322                 if(diff*tangent.perp()<0) diff=-diff;
 323                 diff=diff.norm();
 324         }
 325         else
 326                 diff=tangent.perp();
 327
 328         // diff is a unit vector perpendicular to the bline
 329         const Real unscaled_distance((point_-origin - p1)*diff);
 330         if (dist) *dist = unscaled_distance;
 331         if (along) *along = len;
 332         return ((start_point + (end_point - start_point) * len / curve_length_) +
 333                         perp_ * unscaled_distance/(thickness*perp_width));
 334 }
 335
 336 synfig::Layer::Handle
 337 CurveWarp::hit_check(synfig::Context context, const synfig::Point &point)const
 338 {
 339         return context.hit_check(transform(point));
 340 }
 341
 342 bool
 343 CurveWarp::set_param(const String & param, const ValueBase &value)
 344 {
 345         IMPORT(origin);
 346         IMPORT(start_point);
 347         IMPORT(end_point);
 348         IMPORT(fast);
 349         IMPORT(perp_width);
 350
 351         if(param=="bline" && value.get_type()==ValueBase::TYPE_LIST)
 352         {
 353                 bline=value;
 354                 sync();
 355
 356                 return true;
 357         }
 358
 359         IMPORT_AS(origin,"offset");
 360
 361         return false;
 362 }
 363
 364 ValueBase
 365 CurveWarp::get_param(const String & param)const
 366 {
 367         EXPORT(origin);
 368         EXPORT(start_point);
 369         EXPORT(end_point);
 370         EXPORT(bline);
 371         EXPORT(fast);
 372         EXPORT(perp_width);
 373
 374         EXPORT_NAME();
 375         EXPORT_VERSION();
 376
 377         return ValueBase();
 378 }
 379
 380 Layer::Vocab
 381 CurveWarp::get_param_vocab()const
 382 {
 383         Layer::Vocab ret;
 384
 385         ret.push_back(ParamDesc("origin")
 386                                   .set_local_name(_("Origin")));
 387
 388         ret.push_back(ParamDesc("perp_width")
 389                                   .set_local_name(_("Width"))
 390                                   .set_origin("start_point"));
 391
 392         ret.push_back(ParamDesc("start_point")
 393                                   .set_local_name(_("Start Point"))
 394                                   .set_connect("end_point"));
 395
 396         ret.push_back(ParamDesc("end_point")
 397                                   .set_local_name(_("End Point")));
 398
 399         ret.push_back(ParamDesc("bline")
 400                                   .set_local_name(_("Vertices"))
 401                                   .set_origin("origin")
 402                                   .set_hint("width")
 403                                   .set_description(_("A list of BLine Points")));
 404
 405         ret.push_back(ParamDesc("fast")
 406                                   .set_local_name(_("Fast")));
 407
 408         return ret;
 409 }
 410
 411 Color
 412 CurveWarp::get_color(Context context, const Point &point)const
 413 {
 414         return context.get_color(transform(point));
 415 }
 416
 417 bool
 418 CurveWarp::accelerated_render(Context context,Surface *surface,int quality, const RendDesc &renddesc, ProgressCallback *cb)const
 419 {
 420         SuperCallback stageone(cb,0,9000,10000);
 421         SuperCallback stagetwo(cb,9000,10000,10000);
 422
 423         int x,y;
 424
 425         const Real pw(renddesc.get_pw()),ph(renddesc.get_ph());
 426         Point tl(renddesc.get_tl());
 427         Point br(renddesc.get_br());
 428         const int w(renddesc.get_w());
 429         const int h(renddesc.get_h());
 430
 431         // find a bounding rectangle for the context we need to render
 432         // todo: find a better way of doing this - this way doesn't work
 433         Rect src_rect(transform(tl));
 434         Point pos1, pos2;
 435         Real dist, along;
 436         Real min_dist(999999), max_dist(-999999), min_along(999999), max_along(-999999);
 437
 438 #define UPDATE_DIST \
 439         if (dist < min_dist) min_dist = dist; \
 440         if (dist > max_dist) max_dist = dist; \
 441         if (along < min_along) min_along = along; \
 442         if (along > max_along) max_along = along
 443
 444         // look along the top and bottom edges
 445         pos1[0] = pos2[0] = tl[0]; pos1[1] = tl[1]; pos2[1] = br[1];
 446         for (x = 0; x < w; x++, pos1[0] += pw, pos2[0] += pw)
 447         {
 448                 src_rect.expand(transform(pos1, &dist, &along)); UPDATE_DIST;
 449                 src_rect.expand(transform(pos2, &dist, &along)); UPDATE_DIST;
 450         }
 451
 452         // look along the left and right edges
 453         pos1[0] = tl[0]; pos2[0] = br[0]; pos1[1] = pos2[1] = tl[1];
 454         for (y = 0; y < h; y++, pos1[1] += ph, pos2[1] += ph)
 455         {
 456                 src_rect.expand(transform(pos1, &dist, &along)); UPDATE_DIST;
 457                 src_rect.expand(transform(pos2, &dist, &along)); UPDATE_DIST;
 458         }
 459
 460         // look along the diagonals
 461         const int max_wh(std::max(w,h));
 462         const Real inc_x((br[0]-tl[0])/max_wh),inc_y((br[1]-tl[1])/max_wh);
 463         pos1[0] = pos2[0] = tl[0]; pos1[1] = tl[1]; pos2[1] = br[1];
 464         for (x = 0; x < max_wh; x++, pos1[0] += inc_x, pos2[0] = pos1[0], pos1[1]+=inc_y, pos2[1]-=inc_y)
 465         {
 466                 src_rect.expand(transform(pos1, &dist, &along)); UPDATE_DIST;
 467                 src_rect.expand(transform(pos2, &dist, &along)); UPDATE_DIST;
 468         }
 469
 470 #if 0
 471         // look at each blinepoint
 472         std::vector<synfig::BLinePoint>::const_iterator iter;
 473         for (iter=bline.begin(); iter!=bline.end(); iter++)
 474                 src_rect.expand(transform(iter->get_vertex()+origin, &dist, &along)); UPDATE_DIST;
 475 #endif
 476
 477         Point src_tl(src_rect.get_min());
 478         Point src_br(src_rect.get_max());
 479
 480         Vector ab((end_point - start_point).norm());
 481         Angle::tan ab_angle(ab[1], ab[0]);
 482
 483         Real used_length = max_along - min_along;
 484         Real render_width = max_dist - min_dist;
 485
 486         int src_w = (abs(used_length*Angle::cos(ab_angle).get()) +
 487                                  abs(render_width*Angle::sin(ab_angle).get())) / abs(pw);
 488         int src_h = (abs(used_length*Angle::sin(ab_angle).get()) +
 489                                  abs(render_width*Angle::cos(ab_angle).get())) / abs(ph);
 490
 491         Real src_pw((src_br[0] - src_tl[0]) / src_w);
 492         Real src_ph((src_br[1] - src_tl[1]) / src_h);
 493
 494         if (src_pw > abs(pw))
 495         {
 496                 src_w = int((src_br[0] - src_tl[0]) / abs(pw));
 497                 src_pw = (src_br[0] - src_tl[0]) / src_w;
 498         }
 499
 500         if (src_ph > abs(ph))
 501         {
 502                 src_h = int((src_br[1] - src_tl[1]) / abs(ph));
 503                 src_ph = (src_br[1] - src_tl[1]) / src_h;
 504         }
 505
 506 #define MAXPIX 10000
 507         if (src_w > MAXPIX) src_w = MAXPIX;
 508         if (src_h > MAXPIX) src_h = MAXPIX;
 509
 510         // this is an attempt to remove artifacts around tile edges - the
 511         // cubic interpolation uses at most 2 pixels either side of the
 512         // target pixel, so add an extra 2 pixels around the tile on all
 513         // sides
 514         src_tl -= (Point(src_pw,src_ph)*2);
 515         src_br += (Point(src_pw,src_ph)*2);
 516         src_w += 4;
 517         src_h += 4;
 518         src_pw = (src_br[0] - src_tl[0]) / src_w;
 519         src_ph = (src_br[1] - src_tl[1]) / src_h;
 520
 521         // set up a renddesc for the context to render
 522         RendDesc src_desc(renddesc);
 523         src_desc.clear_flags();
 524         src_desc.set_tl(src_tl);
 525         src_desc.set_br(src_br);
 526         src_desc.set_wh(src_w, src_h);
 527
 528         // render the context onto a new surface
 529         Surface source;
 530         source.set_wh(src_w,src_h);
 531         if(!context.accelerated_render(&source,quality,src_desc,&stageone))
 532                 return false;
 533
 534         float u,v;
 535         Point pos, tmp;
 536
 537         surface->set_wh(w,h);
 538         surface->clear();
 539
 540         if(quality<=4)                          // CUBIC
 541                 for(y=0,pos[1]=tl[1];y<h;y++,pos[1]+=ph)
 542                 {
 543                         for(x=0,pos[0]=tl[0];x<w;x++,pos[0]+=pw)
 544                         {
 545                                 tmp=transform(pos);
 546                                 u=(tmp[0]-src_tl[0])/src_pw;
 547                                 v=(tmp[1]-src_tl[1])/src_ph;
 548                                 if(u<0 || v<0 || u>=src_w || v>=src_h || isnan(u) || isnan(v))
 549                                         (*surface)[y][x]=context.get_color(tmp);
 550                                 else
 551                                         (*surface)[y][x]=source.cubic_sample(u,v);
 552                         }
 553                         if((y&31)==0 && cb && !stagetwo.amount_complete(y,h)) return false;
 554                 }
 555         else if (quality<=6)            // INTERPOLATION_LINEAR
 556                 for(y=0,pos[1]=tl[1];y<h;y++,pos[1]+=ph)
 557                 {
 558                         for(x=0,pos[0]=tl[0];x<w;x++,pos[0]+=pw)
 559                         {
 560                                 tmp=transform(pos);
 561                                 u=(tmp[0]-src_tl[0])/src_pw;
 562                                 v=(tmp[1]-src_tl[1])/src_ph;
 563                                 if(u<0 || v<0 || u>=src_w || v>=src_h || isnan(u) || isnan(v))
 564                                         (*surface)[y][x]=context.get_color(tmp);
 565                                 else
 566                                         (*surface)[y][x]=source.linear_sample(u,v);
 567                         }
 568                         if((y&31)==0 && cb && !stagetwo.amount_complete(y,h)) return false;
 569                 }
 570         else                                            // NEAREST_NEIGHBOR
 571                 for(y=0,pos[1]=tl[1];y<h;y++,pos[1]+=ph)
 572                 {
 573                         for(x=0,pos[0]=tl[0];x<w;x++,pos[0]+=pw)
 574                         {
 575                                 tmp=transform(pos);
 576                                 u=(tmp[0]-src_tl[0])/src_pw;
 577                                 v=(tmp[1]-src_tl[1])/src_ph;
 578                                 if(u<0 || v<0 || u>=src_w || v>=src_h || isnan(u) || isnan(v))
 579                                         (*surface)[y][x]=context.get_color(tmp);
 580                                 else
 581                                         (*surface)[y][x]=source[floor_to_int(v)][floor_to_int(u)];
 582                         }
 583                         if((y&31)==0 && cb && !stagetwo.amount_complete(y,h)) return false;
 584                 }
 585
 586         // Mark our progress as finished
 587         if(cb && !cb->amount_complete(10000,10000))
 588                 return false;
 589
 590         return true;
 591 }