synfig-core/trunk/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/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(CurveWarp);
  58 SYNFIG_LAYER_SET_NAME(CurveWarp,"curve_warp");
  59 SYNFIG_LAYER_SET_LOCAL_NAME(CurveWarp,N_("Curve Warp"));
  60 SYNFIG_LAYER_SET_CATEGORY(CurveWarp,N_("Distortions"));
  61 SYNFIG_LAYER_SET_VERSION(CurveWarp,"0.0");
  62 SYNFIG_LAYER_SET_CVS_ID(CurveWarp,"$Id$");
  63
  64 /* === P R O C E D U R E S ================================================= */
  65
  66 inline float calculate_distance(const std::vector<synfig::BLinePoint>& bline)
  67 {
  68         std::vector<synfig::BLinePoint>::const_iterator iter,next,ret;
  69         std::vector<synfig::BLinePoint>::const_iterator end(bline.end());
  70
  71         float dist(0);
  72
  73         if (bline.empty()) return dist;
  74
  75         next=bline.begin();
  76         iter=next++;
  77
  78         for(;next!=end;iter=next++)
  79         {
  80                 // Setup the curve
  81                 etl::hermite<Vector> curve(iter->get_vertex(), next->get_vertex(), iter->get_tangent2(), next->get_tangent1());
  82                 dist+=curve.length();
  83         }
  84
  85         return dist;
  86 }
  87
  88 std::vector<synfig::BLinePoint>::const_iterator
  89 find_closest_to_bline(bool fast, const std::vector<synfig::BLinePoint>& bline,const Point& p,float& t, float& len, bool& extreme)
  90 {
  91         std::vector<synfig::BLinePoint>::const_iterator iter,next,ret;
  92         std::vector<synfig::BLinePoint>::const_iterator end(bline.end());
  93
  94         ret=bline.end();
  95         float dist(100000000000.0);
  96         next=bline.begin();
  97         float best_pos(0), best_len(0);
  98         etl::hermite<Vector> best_curve;
  99         iter=next++;
 100         Point bp;
 101         float total_len(0);
 102         bool first = true, last = false;
 103         extreme = false;
 104
 105         for(;next!=end;iter=next++)
 106         {
 107                 // Setup the curve
 108                 etl::hermite<Vector> curve(iter->get_vertex(), next->get_vertex(), iter->get_tangent2(), next->get_tangent1());
 109                 float thisdist(0);
 110                 last = false;
 111
 112                 if (fast)
 113                 {
 114 #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;}
 115                         POINT_CHECK(0.0001);  POINT_CHECK((1.0/6)); POINT_CHECK((2.0/6)); POINT_CHECK((3.0/6));
 116                         POINT_CHECK((4.0/6)); POINT_CHECK((5.0/6)); POINT_CHECK(0.9999);
 117                 }
 118                 else
 119                 {
 120                         float pos = curve.find_closest(fast, p);
 121                         thisdist=(curve(pos)-p).mag_squared();
 122                         if(thisdist<dist)
 123                         {
 124                                 extreme = (first && pos == 0);
 125                                 ret=iter;
 126                                 dist=thisdist;
 127                                 best_pos = pos;
 128                                 best_curve = curve;
 129                                 best_len = total_len;
 130                                 last = true;
 131                         }
 132                 }
 133                 total_len += curve.length();
 134                 first = false;
 135         }
 136
 137         t = best_pos;
 138         if (fast)
 139         {
 140                 len = best_len + best_curve.find_distance(0,best_curve.find_closest(fast, p));
 141                 if (last && t > .99) extreme = true;
 142         }
 143         else
 144         {
 145                 len = best_len + best_curve.find_distance(0,best_pos);
 146                 if (last && t == 1) extreme = true;
 147         }
 148         return ret;
 149 }
 150
 151 /* === M E T H O D S ======================================================= */
 152
 153 inline void
 154 CurveWarp::sync()
 155 {
 156         curve_length_=calculate_distance(bline);
 157         perp_ = (end_point - start_point).perp().norm();
 158 }
 159
 160 CurveWarp::CurveWarp():
 161         origin(0,0),
 162         width(1),
 163         start_point(-3,-1),
 164         end_point(3,1),
 165         fast(true)
 166 {
 167         bline.push_back(BLinePoint());
 168         bline.push_back(BLinePoint());
 169         bline[0].set_vertex(Point(-2.5,0));
 170         bline[1].set_vertex(Point(2.5,0));
 171         bline[0].set_tangent(Point(1, 1));
 172         bline[1].set_tangent(Point(1, -1));
 173         bline[0].set_width(1.0f);
 174         bline[1].set_width(1.0f);
 175
 176         sync();
 177 }
 178
 179 inline Point
 180 CurveWarp::transform(const Point &point_, int quality, float supersample)const
 181 {
 182         Vector tangent;
 183         Vector diff;
 184         Point p1;
 185         Real thickness;
 186         Real dist;
 187         bool edge_case = false;
 188         float len(0);
 189         bool extreme;
 190         float t;
 191
 192         if(bline.size()==0)
 193                 return Point();
 194         else if(bline.size()==1)
 195         {
 196                 tangent=bline.front().get_tangent1();
 197                 p1=bline.front().get_vertex();
 198                 thickness=bline.front().get_width();
 199                 t = 0.5;
 200                 extreme = false;
 201         }
 202         else
 203         {
 204                 Point point(point_-origin);
 205
 206                 std::vector<synfig::BLinePoint>::const_iterator iter,next;
 207
 208                 // Figure out the BLinePoint we will be using,
 209                 next=find_closest_to_bline(fast,bline,point,t,len,extreme);
 210
 211                 iter=next++;
 212                 if(next==bline.end()) next=bline.begin();
 213
 214                 // Setup the curve
 215                 etl::hermite<Vector> curve(iter->get_vertex(), next->get_vertex(), iter->get_tangent2(), next->get_tangent1());
 216
 217                 // Setup the derivative function
 218                 etl::derivative<etl::hermite<Vector> > deriv(curve);
 219
 220                 int search_iterations(7);
 221
 222                 if(quality<=6)search_iterations=7;
 223                 else if(quality<=7)search_iterations=6;
 224                 else if(quality<=8)search_iterations=5;
 225                 else search_iterations=4;
 226
 227                 // Figure out the closest point on the curve
 228                 if (fast) t = curve.find_closest(fast, point,search_iterations);
 229
 230                 // Calculate our values
 231                 p1=curve(t);                     // the closest point on the curve
 232                 tangent=deriv(t);                // the tangent at that point
 233
 234                 // if the point we're nearest to is at either end of the
 235                 // bline, our distance from the curve is the distance from the
 236                 // point on the curve.  we need to know which side of the
 237                 // curve we're on, so find the average of the two tangents at
 238                 // this point
 239                 if (t<0.00001 || t>0.99999)
 240                 {
 241                         bool zero_tangent = (tangent[0] == 0 && tangent[1] == 0);
 242
 243                         if (t<0.5)
 244                         {
 245                                 if (iter->get_split_tangent_flag() || zero_tangent)
 246                                 {
 247                                         // fake the current tangent if we need to
 248                                         if (zero_tangent) tangent = curve(FAKE_TANGENT_STEP) - curve(0);
 249
 250                                         // calculate the other tangent
 251                                         Vector other_tangent(iter->get_tangent1());
 252                                         if (other_tangent[0] == 0 && other_tangent[1] == 0)
 253                                         {
 254                                                 // find the previous blinepoint
 255                                                 std::vector<synfig::BLinePoint>::const_iterator prev;
 256                                                 if (iter != bline.begin()) (prev = iter)--;
 257                                                 else prev = iter;
 258
 259                                                 etl::hermite<Vector> other_curve(prev->get_vertex(), iter->get_vertex(), prev->get_tangent2(), iter->get_tangent1());
 260                                                 other_tangent = other_curve(1) - other_curve(1-FAKE_TANGENT_STEP);
 261                                         }
 262
 263                                         // normalise and sum the two tangents
 264                                         tangent=(other_tangent.norm()+tangent.norm());
 265                                         edge_case=true;
 266                                 }
 267                         }
 268                         else
 269                         {
 270                                 if (next->get_split_tangent_flag() || zero_tangent)
 271                                 {
 272                                         // fake the current tangent if we need to
 273                                         if (zero_tangent) tangent = curve(1) - curve(1-FAKE_TANGENT_STEP);
 274
 275                                         // calculate the other tangent
 276                                         Vector other_tangent(next->get_tangent2());
 277                                         if (other_tangent[0] == 0 && other_tangent[1] == 0)
 278                                         {
 279                                                 // find the next blinepoint
 280                                                 std::vector<synfig::BLinePoint>::const_iterator next2(next);
 281                                                 if (++next2 == bline.end())
 282                                                         next2 = next;
 283
 284                                                 etl::hermite<Vector> other_curve(next->get_vertex(), next2->get_vertex(), next->get_tangent2(), next2->get_tangent1());
 285                                                 other_tangent = other_curve(FAKE_TANGENT_STEP) - other_curve(0);
 286                                         }
 287
 288                                         // normalise and sum the two tangents
 289                                         tangent=(other_tangent.norm()+tangent.norm());
 290                                         edge_case=true;
 291                                 }
 292                         }
 293                 }
 294                 tangent = tangent.norm();
 295
 296                 // the width of the bline at the closest point on the curve
 297                 thickness=(next->get_width()-iter->get_width())*t+iter->get_width();
 298         }
 299
 300         if (extreme)
 301         {
 302                 Vector tangent, perp;
 303
 304                 if (t < 0.5)
 305                 {
 306                         synfig::BLinePoint start(bline[0]);
 307                         // Point a(start.get_vertex());
 308                         tangent = start.get_tangent1().norm();
 309                         diff = tangent.perp()*thickness*width;
 310                         len = (point_-origin - p1)*tangent;
 311                 }
 312                 else
 313                 {
 314                         std::vector<synfig::BLinePoint>::const_iterator iter;
 315                         iter=bline.end();
 316                         iter--;
 317                         tangent = iter->get_tangent2().norm();
 318                         diff = tangent.perp()*thickness*width;
 319                         len = (point_-origin - p1)*tangent + curve_length_;
 320                 }
 321         }
 322         else if (edge_case)
 323         {
 324                 diff=(p1-(point_-origin));
 325                 if(diff*tangent.perp()<0) diff=-diff;
 326                 diff=diff.norm()*thickness*width;
 327         }
 328         else
 329                 diff=tangent.perp()*thickness*width;
 330
 331                 const Real mag(diff.inv_mag());
 332                 supersample=supersample*mag;
 333                 diff*=mag*mag;
 334                 dist=(point_-origin - p1)*diff;
 335
 336         len /= curve_length_;
 337
 338         return (start_point + (end_point - start_point) * len) + perp_ * dist;
 339 }
 340
 341 float
 342 CurveWarp::calc_supersample(const synfig::Point &/*x*/, float pw,float /*ph*/)const
 343 {
 344         return pw;
 345 }
 346
 347 synfig::Layer::Handle
 348 CurveWarp::hit_check(synfig::Context context, const synfig::Point &point)const
 349 {
 350         return context.hit_check(transform(point));
 351 }
 352
 353 bool
 354 CurveWarp::set_param(const String & param, const ValueBase &value)
 355 {
 356         IMPORT(origin);
 357         IMPORT(start_point);
 358         IMPORT(end_point);
 359         IMPORT(fast);
 360         IMPORT(width);
 361
 362         if(param=="bline" && value.get_type()==ValueBase::TYPE_LIST)
 363         {
 364                 bline=value;
 365                 sync();
 366
 367                 return true;
 368         }
 369
 370         IMPORT_AS(origin,"offset");
 371
 372         return false;
 373 }
 374
 375 ValueBase
 376 CurveWarp::get_param(const String & param)const
 377 {
 378         EXPORT(origin);
 379         EXPORT(start_point);
 380         EXPORT(end_point);
 381         EXPORT(bline);
 382         EXPORT(fast);
 383         EXPORT(width);
 384
 385         EXPORT_NAME();
 386         EXPORT_VERSION();
 387
 388         return ValueBase();
 389 }
 390
 391 Layer::Vocab
 392 CurveWarp::get_param_vocab()const
 393 {
 394         Layer::Vocab ret;
 395
 396         ret.push_back(ParamDesc("origin")
 397                                   .set_local_name(_("Origin")));
 398
 399         ret.push_back(ParamDesc("width")
 400                                   .set_local_name(_("Width")));
 401
 402         ret.push_back(ParamDesc("start_point")
 403                                   .set_local_name(_("Start Point")));
 404
 405         ret.push_back(ParamDesc("end_point")
 406                                   .set_local_name(_("End Point")));
 407
 408         ret.push_back(ParamDesc("bline")
 409                                   .set_local_name(_("Vertices"))
 410                                   .set_origin("origin")
 411                                   .set_hint("width")
 412                                   .set_description(_("A list of BLine Points")));
 413
 414         ret.push_back(ParamDesc("fast")
 415                                   .set_local_name(_("Fast")));
 416
 417         return ret;
 418 }
 419
 420 Color
 421 CurveWarp::get_color(Context context, const Point &point)const
 422 {
 423         return context.get_color(transform(point));
 424 }
 425
 426 bool
 427 CurveWarp::accelerated_render(Context context,Surface *surface,int quality, const RendDesc &renddesc, ProgressCallback *cb)const
 428 {
 429         SuperCallback supercb(cb,0,9500,10000);
 430
 431         if(!context.accelerated_render(surface,quality,renddesc,&supercb))
 432                 return false;
 433
 434         int x,y;
 435
 436         const Real pw(renddesc.get_pw()),ph(renddesc.get_ph());
 437         Point pos;
 438         Point tl(renddesc.get_tl());
 439         const int w(surface->get_w());
 440         const int h(surface->get_h());
 441
 442         for(y=0,pos[1]=tl[1];y<h;y++,pos[1]+=ph)
 443                 for(x=0,pos[0]=tl[0];x<w;x++,pos[0]+=pw)
 444                         if (1)
 445                                 (*surface)[y][x]=context.get_color(transform(pos));
 446                         else
 447                                 (*surface)[y][x]=context.get_color(transform(pos));
 448
 449         // Mark our progress as finished
 450         if(cb && !cb->amount_complete(10000,10000))
 451                 return false;
 452
 453         return true;
 454 }