synfig-core/src/modules/mod_gradient/curvegradient.cpp

   1 /* === S Y N F I G ========================================================= */
   2 /*!     \file curvegradient.cpp
   3 **      \brief Implementation of the "Curve Gradient" 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 "curvegradient.h"
  36
  37 #include <synfig/string.h>
  38 #include <synfig/time.h>
  39 #include <synfig/context.h>
  40 #include <synfig/paramdesc.h>
  41 #include <synfig/renddesc.h>
  42 #include <synfig/surface.h>
  43 #include <synfig/value.h>
  44 #include <synfig/valuenode.h>
  45 #include <ETL/bezier>
  46 #include <ETL/hermite>
  47 #include <ETL/calculus>
  48
  49 #endif
  50
  51 /* === M A C R O S ========================================================= */
  52
  53 #define FAKE_TANGENT_STEP 0.000001
  54
  55 /* === G L O B A L S ======================================================= */
  56
  57 SYNFIG_LAYER_INIT(CurveGradient);
  58 SYNFIG_LAYER_SET_NAME(CurveGradient,"curve_gradient");
  59 SYNFIG_LAYER_SET_LOCAL_NAME(CurveGradient,N_("Curve Gradient"));
  60 SYNFIG_LAYER_SET_CATEGORY(CurveGradient,N_("Gradients"));
  61 SYNFIG_LAYER_SET_VERSION(CurveGradient,"0.0");
  62 SYNFIG_LAYER_SET_CVS_ID(CurveGradient,"$Id$");
  63
  64 /* === P R O C E D U R E S ================================================= */
  65
  66 inline float calculate_distance(const synfig::BLinePoint& a,const synfig::BLinePoint& b)
  67 {
  68 #if 1
  69         const Point& c1(a.get_vertex());
  70         const Point c2(a.get_vertex()+a.get_tangent2()/3);
  71         const Point c3(b.get_vertex()-b.get_tangent1()/3);
  72         const Point& c4(b.get_vertex());
  73         return (c1-c2).mag()+(c2-c3).mag()+(c3-c4).mag();
  74 #else
  75 #endif
  76 }
  77
  78 inline float calculate_distance(const std::vector<synfig::BLinePoint>& bline, bool bline_loop)
  79 {
  80         std::vector<synfig::BLinePoint>::const_iterator iter,next,ret;
  81         std::vector<synfig::BLinePoint>::const_iterator end(bline.end());
  82
  83         float dist(0);
  84
  85         if (bline.empty()) return dist;
  86
  87         next=bline.begin();
  88
  89         if(bline_loop)
  90                 iter=--bline.end();
  91         else
  92                 iter=next++;
  93
  94         for(;next!=end;iter=next++)
  95         {
  96                 // Setup the curve
  97                 etl::hermite<Vector> curve(
  98                         iter->get_vertex(),
  99                         next->get_vertex(),
 100                         iter->get_tangent2(),
 101                         next->get_tangent1());
 102
 103 //              dist+=calculate_distance(*iter,*next);
 104                 dist+=curve.length();
 105         }
 106
 107         return dist;
 108 }
 109
 110 std::vector<synfig::BLinePoint>::const_iterator
 111 find_closest(bool fast, const std::vector<synfig::BLinePoint>& bline,const Point& p,float& t,bool loop=false,float *bline_dist_ret=0)
 112 {
 113         std::vector<synfig::BLinePoint>::const_iterator iter,next,ret;
 114         std::vector<synfig::BLinePoint>::const_iterator end(bline.end());
 115
 116         ret=bline.end();
 117         float dist(100000000000.0);
 118
 119         next=bline.begin();
 120
 121         float best_bline_dist(0);
 122         float best_bline_len(0);
 123         float total_bline_dist(0);
 124         float best_pos(0);
 125         etl::hermite<Vector> best_curve;
 126
 127         if(loop)
 128                 iter=--bline.end();
 129         else
 130                 iter=next++;
 131
 132         Point bp;
 133
 134         for(;next!=end;iter=next++)
 135         {
 136                 // Setup the curve
 137                 etl::hermite<Vector> curve(
 138                         iter->get_vertex(),
 139                         next->get_vertex(),
 140                         iter->get_tangent2(),
 141                         next->get_tangent1());
 142
 143                 /*
 144                 const float t(curve.find_closest(p,6,0.01,0.99));
 145                 bp=curve(t);if((bp-p).mag_squared()<dist) { ret=iter; dist=(bp-p).mag_squared(); ret_t=t; }
 146                 */
 147
 148                 float thisdist(0);
 149                 float len(0);
 150                 if(bline_dist_ret)
 151                 {
 152                         //len=calculate_distance(*iter,*next);
 153                         len=curve.length();
 154                 }
 155
 156                 if (fast)
 157                 {
 158 #define POINT_CHECK(x) bp=curve(x);     thisdist=(bp-p).mag_squared(); if(thisdist<dist) { ret=iter; dist=thisdist; best_bline_dist=total_bline_dist; best_bline_len=len; best_curve=curve; }
 159                         POINT_CHECK(0.0001);
 160                         POINT_CHECK((1.0/6.0));
 161                         POINT_CHECK((2.0/6.0));
 162                         POINT_CHECK((3.0/6.0));
 163                         POINT_CHECK((4.0/6.0));
 164                         POINT_CHECK((5.0/6.0));
 165                         POINT_CHECK(0.9999);
 166                 }
 167                 else
 168                 {
 169                         float pos = curve.find_closest(fast, p);
 170                         thisdist=(curve(pos)-p).mag_squared();
 171                         if(thisdist<dist)
 172                         {
 173                                 ret=iter;
 174                                 dist=thisdist;
 175                                 best_bline_dist=total_bline_dist;
 176                                 best_bline_len=len;
 177                                 best_curve=curve;
 178                                 best_pos = pos;
 179                         }
 180                 }
 181
 182                 total_bline_dist+=len;
 183         }
 184
 185         t = best_pos;
 186
 187         if(bline_dist_ret)
 188         {
 189                 //! \todo is this a redundant call to find_closest()?
 190                 // note bline_dist_ret is null except when 'perpendicular' is true
 191                 *bline_dist_ret=best_bline_dist+best_curve.find_distance(0,best_curve.find_closest(fast, p));
 192 //              *bline_dist_ret=best_bline_dist+best_curve.find_closest(fast, p)*best_bline_len;
 193         }
 194
 195         return ret;
 196 }
 197
 198 /* === M E T H O D S ======================================================= */
 199
 200 inline void
 201 CurveGradient::sync()
 202 {
 203         curve_length_=calculate_distance(bline, bline_loop);
 204 }
 205
 206
 207 CurveGradient::CurveGradient():
 208         Layer_Composite(1.0,Color::BLEND_COMPOSITE),
 209         origin(0,0),
 210         width(0.25),
 211         gradient(Color::black(), Color::white()),
 212         loop(false),
 213         zigzag(false),
 214         perpendicular(false),
 215         fast(true)
 216 {
 217         bline.push_back(BLinePoint());
 218         bline.push_back(BLinePoint());
 219         bline.push_back(BLinePoint());
 220         bline[0].set_vertex(Point(0,1));
 221         bline[1].set_vertex(Point(0,-1));
 222         bline[2].set_vertex(Point(1,0));
 223         bline[0].set_tangent(bline[1].get_vertex()-bline[2].get_vertex()*0.5f);
 224         bline[1].set_tangent(bline[2].get_vertex()-bline[0].get_vertex()*0.5f);
 225         bline[2].set_tangent(bline[0].get_vertex()-bline[1].get_vertex()*0.5f);
 226         bline[0].set_width(1.0f);
 227         bline[1].set_width(1.0f);
 228         bline[2].set_width(1.0f);
 229         bline_loop=true;
 230
 231         sync();
 232 }
 233
 234 inline Color
 235 CurveGradient::color_func(const Point &point_, int quality, float supersample)const
 236 {
 237         Vector tangent;
 238         Vector diff;
 239         Point p1;
 240         Real thickness;
 241         Real dist;
 242
 243         float perp_dist;
 244         bool edge_case = false;
 245
 246         if(bline.size()==0)
 247                 return Color::alpha();
 248         else if(bline.size()==1)
 249         {
 250                 tangent=bline.front().get_tangent1();
 251                 p1=bline.front().get_vertex();
 252                 thickness=bline.front().get_width();
 253         }
 254         else
 255         {
 256                 float t;
 257                 Point point(point_-origin);
 258
 259                 std::vector<synfig::BLinePoint>::const_iterator iter,next;
 260
 261                 // Figure out the BLinePoints we will be using,
 262                 // Taking into account looping.
 263                 if(perpendicular)
 264                 {
 265                         next=find_closest(fast,bline,point,t,bline_loop,&perp_dist);
 266                         perp_dist/=curve_length_;
 267                 }
 268                 else                                    // not perpendicular
 269                 {
 270                         next=find_closest(fast,bline,point,t,bline_loop);
 271                 }
 272
 273                 iter=next++;
 274                 if(next==bline.end()) next=bline.begin();
 275
 276                 // Setup the curve
 277                 etl::hermite<Vector> curve(
 278                         iter->get_vertex(),
 279                         next->get_vertex(),
 280                         iter->get_tangent2(),
 281                         next->get_tangent1()
 282                         );
 283
 284                 // Setup the derivative function
 285                 etl::derivative<etl::hermite<Vector> > deriv(curve);
 286
 287                 int search_iterations(7);
 288
 289                 /*if(quality==0)search_iterations=8;
 290                   else if(quality<=2)search_iterations=10;
 291                   else if(quality<=4)search_iterations=8;
 292                 */
 293                 if(perpendicular)
 294                 {
 295                         if(quality>7)
 296                                 search_iterations=4;
 297                 }
 298                 else                                    // not perpendicular
 299                 {
 300                         if(quality<=6)search_iterations=7;
 301                         else if(quality<=7)search_iterations=6;
 302                         else if(quality<=8)search_iterations=5;
 303                         else search_iterations=4;
 304                 }
 305
 306                 // Figure out the closest point on the curve
 307                 if (fast)
 308                         t = curve.find_closest(fast, point,search_iterations);
 309
 310                 // Calculate our values
 311                 p1=curve(t);                     // the closest point on the curve
 312                 tangent=deriv(t);                // the tangent at that point
 313
 314                 // if the point we're nearest to is at either end of the
 315                 // bline, our distance from the curve is the distance from the
 316                 // point on the curve.  we need to know which side of the
 317                 // curve we're on, so find the average of the two tangents at
 318                 // this point
 319                 if (t<0.00001 || t>0.99999)
 320                 {
 321                         bool zero_tangent = (tangent[0] == 0 && tangent[1] == 0);
 322
 323                         if (t<0.5)
 324                         {
 325                                 if (iter->get_split_tangent_flag() || zero_tangent)
 326                                 {
 327                                         // fake the current tangent if we need to
 328                                         if (zero_tangent) tangent = curve(FAKE_TANGENT_STEP) - curve(0);
 329
 330                                         // calculate the other tangent
 331                                         Vector other_tangent(iter->get_tangent1());
 332                                         if (other_tangent[0] == 0 && other_tangent[1] == 0)
 333                                         {
 334                                                 // find the previous blinepoint
 335                                                 std::vector<synfig::BLinePoint>::const_iterator prev;
 336                                                 if (iter != bline.begin()) (prev = iter)--;
 337                                                 else if (loop) (prev = bline.end())--;
 338                                                 else prev = iter;
 339
 340                                                 etl::hermite<Vector> other_curve(prev->get_vertex(), iter->get_vertex(), prev->get_tangent2(), iter->get_tangent1());
 341                                                 other_tangent = other_curve(1) - other_curve(1-FAKE_TANGENT_STEP);
 342                                         }
 343
 344                                         // normalise and sum the two tangents
 345                                         tangent=(other_tangent.norm()+tangent.norm());
 346                                         edge_case=true;
 347                                 }
 348                         }
 349                         else
 350                         {
 351                                 if (next->get_split_tangent_flag() || zero_tangent)
 352                                 {
 353                                         // fake the current tangent if we need to
 354                                         if (zero_tangent) tangent = curve(1) - curve(1-FAKE_TANGENT_STEP);
 355
 356                                         // calculate the other tangent
 357                                         Vector other_tangent(next->get_tangent2());
 358                                         if (other_tangent[0] == 0 && other_tangent[1] == 0)
 359                                         {
 360                                                 // find the next blinepoint
 361                                                 std::vector<synfig::BLinePoint>::const_iterator next2(next);
 362                                                 if (++next2 == bline.end())
 363                                                 {
 364                                                         if (loop) next2 = bline.begin();
 365                                                         else next2 = next;
 366                                                 }
 367
 368                                                 etl::hermite<Vector> other_curve(next->get_vertex(), next2->get_vertex(), next->get_tangent2(), next2->get_tangent1());
 369                                                 other_tangent = other_curve(FAKE_TANGENT_STEP) - other_curve(0);
 370                                         }
 371
 372                                         // normalise and sum the two tangents
 373                                         tangent=(other_tangent.norm()+tangent.norm());
 374                                         edge_case=true;
 375                                 }
 376                         }
 377                 }
 378                 tangent = tangent.norm();
 379
 380                 if(perpendicular)
 381                 {
 382                         tangent*=curve_length_;
 383                         p1-=tangent*perp_dist;
 384                         tangent=-tangent.perp();
 385                 }
 386                 else                                    // not perpendicular
 387                         // the width of the bline at the closest point on the curve
 388                         thickness=(next->get_width()-iter->get_width())*t+iter->get_width();
 389         }
 390
 391         if(perpendicular)
 392         {
 393                 if(quality>7)
 394                 {
 395                         dist=perp_dist;
 396 /*                      diff=tangent.perp();
 397                         const Real mag(diff.inv_mag());
 398                         supersample=supersample*mag;
 399 */
 400                         supersample=0;
 401                 }
 402                 else
 403                 {
 404                         diff=tangent.perp();
 405                         //p1-=diff*0.5;
 406                         const Real mag(diff.inv_mag());
 407                         supersample=supersample*mag;
 408                         diff*=mag*mag;
 409                         dist=(point_-origin - p1)*diff;
 410                 }
 411         }
 412         else                                            // not perpendicular
 413         {
 414                 if (edge_case)
 415                 {
 416                         diff=(p1-(point_-origin));
 417                         if(diff*tangent.perp()<0) diff=-diff;
 418                         diff=diff.norm()*thickness*width;
 419                 }
 420                 else
 421                         diff=tangent.perp()*thickness*width;
 422
 423                 p1-=diff*0.5;
 424                 const Real mag(diff.inv_mag());
 425                 supersample=supersample*mag;
 426                 diff*=mag*mag;
 427                 dist=(point_-origin - p1)*diff;
 428         }
 429
 430         if(loop)
 431                 dist-=floor(dist);
 432
 433         if(zigzag)
 434         {
 435                 dist*=2.0;
 436                 supersample*=2.0;
 437                 if(dist>1)dist=2.0-dist;
 438         }
 439
 440         if(loop)
 441         {
 442                 if(dist+supersample*0.5>1.0)
 443                 {
 444                         float  left(supersample*0.5-(dist-1.0));
 445                         float right(supersample*0.5+(dist-1.0));
 446                         Color pool(gradient(1.0-(left*0.5),left).premult_alpha()*left/supersample);
 447                         if (zigzag) pool+=gradient(1.0-right*0.5,right).premult_alpha()*right/supersample;
 448                         else            pool+=gradient(right*0.5,right).premult_alpha()*right/supersample;
 449                         return pool.demult_alpha();
 450                 }
 451                 if(dist-supersample*0.5<0.0)
 452                 {
 453                         float  left(supersample*0.5-dist);
 454                         float right(supersample*0.5+dist);
 455                         Color pool(gradient(right*0.5,right).premult_alpha()*right/supersample);
 456                         if (zigzag) pool+=gradient(left*0.5,left).premult_alpha()*left/supersample;
 457                         else            pool+=gradient(1.0-left*0.5,left).premult_alpha()*left/supersample;
 458                         return pool.demult_alpha();
 459                 }
 460         }
 461         return gradient(dist,supersample);
 462 }
 463
 464 float
 465 CurveGradient::calc_supersample(const synfig::Point &/*x*/, float pw,float /*ph*/)const
 466 {
 467         return pw;
 468 }
 469
 470 synfig::Layer::Handle
 471 CurveGradient::hit_check(synfig::Context context, const synfig::Point &point)const
 472 {
 473         if(get_blend_method()==Color::BLEND_STRAIGHT && get_amount()>=0.5)
 474                 return const_cast<CurveGradient*>(this);
 475         if(get_amount()==0.0)
 476                 return context.hit_check(point);
 477         if((get_blend_method()==Color::BLEND_STRAIGHT || get_blend_method()==Color::BLEND_COMPOSITE|| get_blend_method()==Color::BLEND_ONTO) && color_func(point).get_a()>0.5)
 478                 return const_cast<CurveGradient*>(this);
 479         return context.hit_check(point);
 480 }
 481
 482 bool
 483 CurveGradient::set_param(const String & param, const ValueBase &value)
 484 {
 485
 486
 487         IMPORT(origin);
 488         IMPORT(perpendicular);
 489         IMPORT(fast);
 490
 491         if(param=="bline" && value.get_type()==ValueBase::TYPE_LIST)
 492         {
 493                 bline=value;
 494                 bline_loop=value.get_loop();
 495                 sync();
 496
 497                 return true;
 498         }
 499
 500         IMPORT(width);
 501         IMPORT(gradient);
 502         IMPORT(loop);
 503         IMPORT(zigzag);
 504
 505         IMPORT_AS(origin,"offset");
 506
 507         return Layer_Composite::set_param(param,value);
 508 }
 509
 510 ValueBase
 511 CurveGradient::get_param(const String & param)const
 512 {
 513         EXPORT(origin);
 514         EXPORT(bline);
 515         EXPORT(gradient);
 516         EXPORT(loop);
 517         EXPORT(zigzag);
 518         EXPORT(width);
 519         EXPORT(perpendicular);
 520         EXPORT(fast);
 521
 522         EXPORT_NAME();
 523         EXPORT_VERSION();
 524
 525         return Layer_Composite::get_param(param);
 526 }
 527
 528 Layer::Vocab
 529 CurveGradient::get_param_vocab()const
 530 {
 531         Layer::Vocab ret(Layer_Composite::get_param_vocab());
 532
 533         ret.push_back(ParamDesc("origin")
 534                                   .set_local_name(_("Origin")));
 535
 536         ret.push_back(ParamDesc("width")
 537                                   .set_is_distance()
 538                                   .set_local_name(_("Width")));
 539
 540         ret.push_back(ParamDesc("bline")
 541                                   .set_local_name(_("Vertices"))
 542                                   .set_origin("origin")
 543                                   .set_hint("width")
 544                                   .set_description(_("A list of BLine Points")));
 545
 546         ret.push_back(ParamDesc("gradient")
 547                                   .set_local_name(_("Gradient")));
 548         ret.push_back(ParamDesc("loop")
 549                                   .set_local_name(_("Loop")));
 550         ret.push_back(ParamDesc("zigzag")
 551                                   .set_local_name(_("ZigZag")));
 552         ret.push_back(ParamDesc("perpendicular")
 553                                   .set_local_name(_("Perpendicular")));
 554         ret.push_back(ParamDesc("fast")
 555                                   .set_local_name(_("Fast")));
 556
 557         return ret;
 558 }
 559
 560 Color
 561 CurveGradient::get_color(Context context, const Point &point)const
 562 {
 563         const Color color(color_func(point,0));
 564
 565         if(get_amount()==1.0 && get_blend_method()==Color::BLEND_STRAIGHT)
 566                 return color;
 567         else
 568                 return Color::blend(color,context.get_color(point),get_amount(),get_blend_method());
 569 }
 570
 571 bool
 572 CurveGradient::accelerated_render(Context context,Surface *surface,int quality, const RendDesc &renddesc, ProgressCallback *cb)const
 573 {
 574         SuperCallback supercb(cb,0,9500,10000);
 575
 576         if(get_amount()==1.0 && get_blend_method()==Color::BLEND_STRAIGHT)
 577         {
 578                 surface->set_wh(renddesc.get_w(),renddesc.get_h());
 579         }
 580         else
 581         {
 582                 if(!context.accelerated_render(surface,quality,renddesc,&supercb))
 583                         return false;
 584                 if(get_amount()==0)
 585                         return true;
 586         }
 587
 588
 589         int x,y;
 590
 591         Surface::pen pen(surface->begin());
 592         const Real pw(renddesc.get_pw()),ph(renddesc.get_ph());
 593         Point pos;
 594         Point tl(renddesc.get_tl());
 595         const int w(surface->get_w());
 596         const int h(surface->get_h());
 597
 598         if(get_amount()==1.0 && get_blend_method()==Color::BLEND_STRAIGHT)
 599         {
 600                 for(y=0,pos[1]=tl[1];y<h;y++,pen.inc_y(),pen.dec_x(x),pos[1]+=ph)
 601                         for(x=0,pos[0]=tl[0];x<w;x++,pen.inc_x(),pos[0]+=pw)
 602                                 pen.put_value(color_func(pos,quality,calc_supersample(pos,pw,ph)));
 603         }
 604         else
 605         {
 606                 for(y=0,pos[1]=tl[1];y<h;y++,pen.inc_y(),pen.dec_x(x),pos[1]+=ph)
 607                         for(x=0,pos[0]=tl[0];x<w;x++,pen.inc_x(),pos[0]+=pw)
 608                                 pen.put_value(Color::blend(color_func(pos,quality,calc_supersample(pos,pw,ph)),pen.get_value(),get_amount(),get_blend_method()));
 609         }
 610
 611         // Mark our progress as finished
 612         if(cb && !cb->amount_complete(10000,10000))
 613                 return false;
 614
 615         return true;
 616 }