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         Layer::Vocab voc(get_param_vocab());
 233         Layer::fill_static(voc);
 234 }
 235
 236 inline Color
 237 CurveGradient::color_func(const Point &point_, int quality, float supersample)const
 238 {
 239         Vector tangent;
 240         Vector diff;
 241         Point p1;
 242         Real thickness;
 243         Real dist;
 244
 245         float perp_dist;
 246         bool edge_case = false;
 247
 248         if(bline.size()==0)
 249                 return Color::alpha();
 250         else if(bline.size()==1)
 251         {
 252                 tangent=bline.front().get_tangent1();
 253                 p1=bline.front().get_vertex();
 254                 thickness=bline.front().get_width();
 255         }
 256         else
 257         {
 258                 float t;
 259                 Point point(point_-origin);
 260
 261                 std::vector<synfig::BLinePoint>::const_iterator iter,next;
 262
 263                 // Figure out the BLinePoints we will be using,
 264                 // Taking into account looping.
 265                 if(perpendicular)
 266                 {
 267                         next=find_closest(fast,bline,point,t,bline_loop,&perp_dist);
 268                         perp_dist/=curve_length_;
 269                 }
 270                 else                                    // not perpendicular
 271                 {
 272                         next=find_closest(fast,bline,point,t,bline_loop);
 273                 }
 274
 275                 iter=next++;
 276                 if(next==bline.end()) next=bline.begin();
 277
 278                 // Setup the curve
 279                 etl::hermite<Vector> curve(
 280                         iter->get_vertex(),
 281                         next->get_vertex(),
 282                         iter->get_tangent2(),
 283                         next->get_tangent1()
 284                         );
 285
 286                 // Setup the derivative function
 287                 etl::derivative<etl::hermite<Vector> > deriv(curve);
 288
 289                 int search_iterations(7);
 290
 291                 /*if(quality==0)search_iterations=8;
 292                   else if(quality<=2)search_iterations=10;
 293                   else if(quality<=4)search_iterations=8;
 294                 */
 295                 if(perpendicular)
 296                 {
 297                         if(quality>7)
 298                                 search_iterations=4;
 299                 }
 300                 else                                    // not perpendicular
 301                 {
 302                         if(quality<=6)search_iterations=7;
 303                         else if(quality<=7)search_iterations=6;
 304                         else if(quality<=8)search_iterations=5;
 305                         else search_iterations=4;
 306                 }
 307
 308                 // Figure out the closest point on the curve
 309                 if (fast)
 310                         t = curve.find_closest(fast, point,search_iterations);
 311
 312                 // Calculate our values
 313                 p1=curve(t);                     // the closest point on the curve
 314                 tangent=deriv(t);                // the tangent at that point
 315
 316                 // if the point we're nearest to is at either end of the
 317                 // bline, our distance from the curve is the distance from the
 318                 // point on the curve.  we need to know which side of the
 319                 // curve we're on, so find the average of the two tangents at
 320                 // this point
 321                 if (t<0.00001 || t>0.99999)
 322                 {
 323                         bool zero_tangent = (tangent[0] == 0 && tangent[1] == 0);
 324
 325                         if (t<0.5)
 326                         {
 327                                 if (iter->get_split_tangent_flag() || zero_tangent)
 328                                 {
 329                                         // fake the current tangent if we need to
 330                                         if (zero_tangent) tangent = curve(FAKE_TANGENT_STEP) - curve(0);
 331
 332                                         // calculate the other tangent
 333                                         Vector other_tangent(iter->get_tangent1());
 334                                         if (other_tangent[0] == 0 && other_tangent[1] == 0)
 335                                         {
 336                                                 // find the previous blinepoint
 337                                                 std::vector<synfig::BLinePoint>::const_iterator prev;
 338                                                 if (iter != bline.begin()) (prev = iter)--;
 339                                                 else if (loop) (prev = bline.end())--;
 340                                                 else prev = iter;
 341
 342                                                 etl::hermite<Vector> other_curve(prev->get_vertex(), iter->get_vertex(), prev->get_tangent2(), iter->get_tangent1());
 343                                                 other_tangent = other_curve(1) - other_curve(1-FAKE_TANGENT_STEP);
 344                                         }
 345
 346                                         // normalise and sum the two tangents
 347                                         tangent=(other_tangent.norm()+tangent.norm());
 348                                         edge_case=true;
 349                                 }
 350                         }
 351                         else
 352                         {
 353                                 if (next->get_split_tangent_flag() || zero_tangent)
 354                                 {
 355                                         // fake the current tangent if we need to
 356                                         if (zero_tangent) tangent = curve(1) - curve(1-FAKE_TANGENT_STEP);
 357
 358                                         // calculate the other tangent
 359                                         Vector other_tangent(next->get_tangent2());
 360                                         if (other_tangent[0] == 0 && other_tangent[1] == 0)
 361                                         {
 362                                                 // find the next blinepoint
 363                                                 std::vector<synfig::BLinePoint>::const_iterator next2(next);
 364                                                 if (++next2 == bline.end())
 365                                                 {
 366                                                         if (loop) next2 = bline.begin();
 367                                                         else next2 = next;
 368                                                 }
 369
 370                                                 etl::hermite<Vector> other_curve(next->get_vertex(), next2->get_vertex(), next->get_tangent2(), next2->get_tangent1());
 371                                                 other_tangent = other_curve(FAKE_TANGENT_STEP) - other_curve(0);
 372                                         }
 373
 374                                         // normalise and sum the two tangents
 375                                         tangent=(other_tangent.norm()+tangent.norm());
 376                                         edge_case=true;
 377                                 }
 378                         }
 379                 }
 380                 tangent = tangent.norm();
 381
 382                 if(perpendicular)
 383                 {
 384                         tangent*=curve_length_;
 385                         p1-=tangent*perp_dist;
 386                         tangent=-tangent.perp();
 387                 }
 388                 else                                    // not perpendicular
 389                         // the width of the bline at the closest point on the curve
 390                         thickness=(next->get_width()-iter->get_width())*t+iter->get_width();
 391         }
 392
 393         if(perpendicular)
 394         {
 395                 if(quality>7)
 396                 {
 397                         dist=perp_dist;
 398 /*                      diff=tangent.perp();
 399                         const Real mag(diff.inv_mag());
 400                         supersample=supersample*mag;
 401 */
 402                         supersample=0;
 403                 }
 404                 else
 405                 {
 406                         diff=tangent.perp();
 407                         //p1-=diff*0.5;
 408                         const Real mag(diff.inv_mag());
 409                         supersample=supersample*mag;
 410                         diff*=mag*mag;
 411                         dist=(point_-origin - p1)*diff;
 412                 }
 413         }
 414         else                                            // not perpendicular
 415         {
 416                 if (edge_case)
 417                 {
 418                         diff=(p1-(point_-origin));
 419                         if(diff*tangent.perp()<0) diff=-diff;
 420                         diff=diff.norm()*thickness*width;
 421                 }
 422                 else
 423                         diff=tangent.perp()*thickness*width;
 424
 425                 p1-=diff*0.5;
 426                 const Real mag(diff.inv_mag());
 427                 supersample=supersample*mag;
 428                 diff*=mag*mag;
 429                 dist=(point_-origin - p1)*diff;
 430         }
 431
 432         if(loop)
 433                 dist-=floor(dist);
 434
 435         if(zigzag)
 436         {
 437                 dist*=2.0;
 438                 supersample*=2.0;
 439                 if(dist>1)dist=2.0-dist;
 440         }
 441
 442         if(loop)
 443         {
 444                 if(dist+supersample*0.5>1.0)
 445                 {
 446                         float  left(supersample*0.5-(dist-1.0));
 447                         float right(supersample*0.5+(dist-1.0));
 448                         Color pool(gradient(1.0-(left*0.5),left).premult_alpha()*left/supersample);
 449                         if (zigzag) pool+=gradient(1.0-right*0.5,right).premult_alpha()*right/supersample;
 450                         else            pool+=gradient(right*0.5,right).premult_alpha()*right/supersample;
 451                         return pool.demult_alpha();
 452                 }
 453                 if(dist-supersample*0.5<0.0)
 454                 {
 455                         float  left(supersample*0.5-dist);
 456                         float right(supersample*0.5+dist);
 457                         Color pool(gradient(right*0.5,right).premult_alpha()*right/supersample);
 458                         if (zigzag) pool+=gradient(left*0.5,left).premult_alpha()*left/supersample;
 459                         else            pool+=gradient(1.0-left*0.5,left).premult_alpha()*left/supersample;
 460                         return pool.demult_alpha();
 461                 }
 462         }
 463         return gradient(dist,supersample);
 464 }
 465
 466 float
 467 CurveGradient::calc_supersample(const synfig::Point &/*x*/, float pw,float /*ph*/)const
 468 {
 469         return pw;
 470 }
 471
 472 synfig::Layer::Handle
 473 CurveGradient::hit_check(synfig::Context context, const synfig::Point &point)const
 474 {
 475         if(get_blend_method()==Color::BLEND_STRAIGHT && get_amount()>=0.5)
 476                 return const_cast<CurveGradient*>(this);
 477         if(get_amount()==0.0)
 478                 return context.hit_check(point);
 479         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)
 480                 return const_cast<CurveGradient*>(this);
 481         return context.hit_check(point);
 482 }
 483
 484 bool
 485 CurveGradient::set_param(const String & param, const ValueBase &value)
 486 {
 487
 488
 489         IMPORT(origin);
 490         IMPORT(perpendicular);
 491         IMPORT(fast);
 492
 493         if(param=="bline" && value.get_type()==ValueBase::TYPE_LIST)
 494         {
 495                 bline=value;
 496                 bline_loop=value.get_loop();
 497                 sync();
 498
 499                 return true;
 500         }
 501
 502         IMPORT(width);
 503         IMPORT(gradient);
 504         IMPORT(loop);
 505         IMPORT(zigzag);
 506
 507         IMPORT_AS(origin,"offset");
 508
 509         return Layer_Composite::set_param(param,value);
 510 }
 511
 512 ValueBase
 513 CurveGradient::get_param(const String & param)const
 514 {
 515         EXPORT(origin);
 516         EXPORT(bline);
 517         EXPORT(gradient);
 518         EXPORT(loop);
 519         EXPORT(zigzag);
 520         EXPORT(width);
 521         EXPORT(perpendicular);
 522         EXPORT(fast);
 523
 524         EXPORT_NAME();
 525         EXPORT_VERSION();
 526
 527         return Layer_Composite::get_param(param);
 528 }
 529
 530 Layer::Vocab
 531 CurveGradient::get_param_vocab()const
 532 {
 533         Layer::Vocab ret(Layer_Composite::get_param_vocab());
 534
 535         ret.push_back(ParamDesc("origin")
 536                                   .set_local_name(_("Origin")));
 537
 538         ret.push_back(ParamDesc("width")
 539                                   .set_is_distance()
 540                                   .set_local_name(_("Width")));
 541
 542         ret.push_back(ParamDesc("bline")
 543                                   .set_local_name(_("Vertices"))
 544                                   .set_origin("origin")
 545                                   .set_hint("width")
 546                                   .set_description(_("A list of BLine Points")));
 547
 548         ret.push_back(ParamDesc("gradient")
 549                                   .set_local_name(_("Gradient")));
 550         ret.push_back(ParamDesc("loop")
 551                                   .set_local_name(_("Loop")));
 552         ret.push_back(ParamDesc("zigzag")
 553                                   .set_local_name(_("ZigZag")));
 554         ret.push_back(ParamDesc("perpendicular")
 555                                   .set_local_name(_("Perpendicular")));
 556         ret.push_back(ParamDesc("fast")
 557                                   .set_local_name(_("Fast")));
 558
 559         return ret;
 560 }
 561
 562 Color
 563 CurveGradient::get_color(Context context, const Point &point)const
 564 {
 565         const Color color(color_func(point,0));
 566
 567         if(get_amount()==1.0 && get_blend_method()==Color::BLEND_STRAIGHT)
 568                 return color;
 569         else
 570                 return Color::blend(color,context.get_color(point),get_amount(),get_blend_method());
 571 }
 572
 573 bool
 574 CurveGradient::accelerated_render(Context context,Surface *surface,int quality, const RendDesc &renddesc, ProgressCallback *cb)const
 575 {
 576         SuperCallback supercb(cb,0,9500,10000);
 577
 578         if(get_amount()==1.0 && get_blend_method()==Color::BLEND_STRAIGHT)
 579         {
 580                 surface->set_wh(renddesc.get_w(),renddesc.get_h());
 581         }
 582         else
 583         {
 584                 if(!context.accelerated_render(surface,quality,renddesc,&supercb))
 585                         return false;
 586                 if(get_amount()==0)
 587                         return true;
 588         }
 589
 590
 591         int x,y;
 592
 593         Surface::pen pen(surface->begin());
 594         const Real pw(renddesc.get_pw()),ph(renddesc.get_ph());
 595         Point pos;
 596         Point tl(renddesc.get_tl());
 597         const int w(surface->get_w());
 598         const int h(surface->get_h());
 599
 600         if(get_amount()==1.0 && get_blend_method()==Color::BLEND_STRAIGHT)
 601         {
 602                 for(y=0,pos[1]=tl[1];y<h;y++,pen.inc_y(),pen.dec_x(x),pos[1]+=ph)
 603                         for(x=0,pos[0]=tl[0];x<w;x++,pen.inc_x(),pos[0]+=pw)
 604                                 pen.put_value(color_func(pos,quality,calc_supersample(pos,pw,ph)));
 605         }
 606         else
 607         {
 608                 for(y=0,pos[1]=tl[1];y<h;y++,pen.inc_y(),pen.dec_x(x),pos[1]+=ph)
 609                         for(x=0,pos[0]=tl[0];x<w;x++,pen.inc_x(),pos[0]+=pw)
 610                                 pen.put_value(Color::blend(color_func(pos,quality,calc_supersample(pos,pw,ph)),pen.get_value(),get_amount(),get_blend_method()));
 611         }
 612
 613         // Mark our progress as finished
 614         if(cb && !cb->amount_complete(10000,10000))
 615                 return false;
 616
 617         return true;
 618 }