src/graphics/PreviewLoader.cpp

   1 /**
   2  * \file PreviewLoader.cpp
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author Angus Leeming
   7  *
   8  * Full author contact details are available in file CREDITS.
   9  */
  10
  11 #include <config.h>
  12
  13 #include "PreviewLoader.h"
  14 #include "PreviewImage.h"
  15 #include "GraphicsCache.h"
  16
  17 #include "Buffer.h"
  18 #include "BufferParams.h"
  19 #include "Converter.h"
  20 #include "Encoding.h"
  21 #include "Format.h"
  22 #include "InsetIterator.h"
  23 #include "LaTeXFeatures.h"
  24 #include "LyXRC.h"
  25 #include "output.h"
  26 #include "OutputParams.h"
  27 #include "TexRow.h"
  28
  29 #include "frontends/Application.h" // hexName
  30
  31 #include "insets/Inset.h"
  32
  33 #include "support/convert.h"
  34 #include "support/debug.h"
  35 #include "support/FileName.h"
  36 #include "support/filetools.h"
  37 #include "support/ForkedCalls.h"
  38 #include "support/lstrings.h"
  39
  40 #include "support/bind.h"
  41 #include "support/TempFile.h"
  42
  43 #include <sstream>
  44 #include <fstream>
  45 #include <iomanip>
  46
  47 #include <QTimer>
  48
  49 using namespace std;
  50 using namespace lyx::support;
  51
  52
  53
  54 namespace {
  55
  56 typedef pair<string, FileName> SnippetPair;
  57
  58 // A list of all snippets to be converted to previews
  59 typedef list<string> PendingSnippets;
  60
  61 // Each item in the vector is a pair<snippet, image file name>.
  62 typedef vector<SnippetPair> BitmapFile;
  63
  64
  65 FileName const unique_tex_filename(FileName const & bufferpath)
  66 {
  67         TempFile tempfile(bufferpath, "lyxpreviewXXXXXX.tex");
  68         tempfile.setAutoRemove(false);
  69         return tempfile.name();
  70 }
  71
  72
  73 lyx::Converter const * setConverter(string const & from)
  74 {
  75         typedef vector<string> FmtList;
  76         typedef lyx::graphics::Cache GCache;
  77         FmtList const & loadableFormats = GCache::get().loadableFormats();
  78         FmtList::const_iterator it = loadableFormats.begin();
  79         FmtList::const_iterator const end = loadableFormats.end();
  80
  81         for (; it != end; ++it) {
  82                 string const to = *it;
  83                 if (from == to)
  84                         continue;
  85
  86                 lyx::Converter const * ptr = lyx::theConverters().getConverter(from, to);
  87                 if (ptr)
  88                         return ptr;
  89         }
  90
  91         // FIXME THREAD
  92         static bool first = true;
  93         if (first) {
  94                 first = false;
  95                 LYXERR0("PreviewLoader::startLoading()\n"
  96                         << "No converter from \"" << from << "\" format has been defined.");
  97         }
  98         return 0;
  99 }
 100
 101
 102 void setAscentFractions(vector<double> & ascent_fractions,
 103                         FileName const & metrics_file)
 104 {
 105         // If all else fails, then the images will have equal ascents and
 106         // descents.
 107         vector<double>::iterator it  = ascent_fractions.begin();
 108         vector<double>::iterator end = ascent_fractions.end();
 109         fill(it, end, 0.5);
 110
 111         ifstream in(metrics_file.toFilesystemEncoding().c_str());
 112         if (!in.good()) {
 113                 LYXERR(lyx::Debug::GRAPHICS, "setAscentFractions(" << metrics_file << ")\n"
 114                         << "Unable to open file!");
 115                 return;
 116         }
 117
 118         bool error = false;
 119
 120         int snippet_counter = 1;
 121         while (!in.eof() && it != end) {
 122                 string snippet;
 123                 int id;
 124                 double ascent_fraction;
 125
 126                 in >> snippet >> id >> ascent_fraction;
 127
 128                 if (!in.good())
 129                         // eof after all
 130                         break;
 131
 132                 error = snippet != "Snippet";
 133                 if (error)
 134                         break;
 135
 136                 error = id != snippet_counter;
 137                 if (error)
 138                         break;
 139
 140                 *it = ascent_fraction;
 141
 142                 ++snippet_counter;
 143                 ++it;
 144         }
 145
 146         if (error) {
 147                 LYXERR(lyx::Debug::GRAPHICS, "setAscentFractions(" << metrics_file << ")\n"
 148                         << "Error reading file!\n");
 149         }
 150 }
 151
 152
 153 class FindFirst
 154 {
 155 public:
 156         FindFirst(string const & comp) : comp_(comp) {}
 157         bool operator()(SnippetPair const & sp) const { return sp.first == comp_; }
 158 private:
 159         string const comp_;
 160 };
 161
 162
 163 /// Store info on a currently executing, forked process.
 164 class InProgress {
 165 public:
 166         ///
 167         InProgress() : pid(0) {}
 168         ///
 169         InProgress(string const & filename_base,
 170                    PendingSnippets const & pending,
 171                    string const & to_format);
 172         /// Remove any files left lying around and kill the forked process.
 173         void stop() const;
 174
 175         ///
 176         pid_t pid;
 177         ///
 178         string command;
 179         ///
 180         FileName metrics_file;
 181         ///
 182         BitmapFile snippets;
 183 };
 184
 185 typedef map<pid_t, InProgress>  InProgressProcesses;
 186
 187 typedef InProgressProcesses::value_type InProgressProcess;
 188
 189 } // namespace anon
 190
 191
 192
 193 namespace lyx {
 194 namespace graphics {
 195
 196 class PreviewLoader::Impl : public boost::signals::trackable {
 197 public:
 198         ///
 199         Impl(PreviewLoader & p, Buffer const & b);
 200         /// Stop any InProgress items still executing.
 201         ~Impl();
 202         ///
 203         PreviewImage const * preview(string const & latex_snippet) const;
 204         ///
 205         PreviewLoader::Status status(string const & latex_snippet) const;
 206         ///
 207         void add(string const & latex_snippet);
 208         ///
 209         void remove(string const & latex_snippet);
 210         /// Record math macro definitions added to the loader
 211         void addMacroDef(docstring const & latex_snippet);
 212         /// Has a math macro definition already been added to the loader?
 213         bool hasMacroDef(docstring const & latex_snippet) const;
 214         /// \p wait whether to wait for the process to complete or, instead,
 215         /// to do it in the background.
 216         void startLoading(bool wait = false);
 217         ///
 218         void refreshPreviews();
 219
 220         /// Emit this signal when an image is ready for display.
 221         boost::signal<void(PreviewImage const &)> imageReady;
 222
 223         Buffer const & buffer() const { return buffer_; }
 224
 225 private:
 226         /// Called by the ForkedCall process that generated the bitmap files.
 227         void finishedGenerating(pid_t, int);
 228         ///
 229         void dumpPreamble(otexstream &, OutputParams::FLAVOR) const;
 230         ///
 231         void dumpData(odocstream &, BitmapFile const &) const;
 232
 233         /** cache_ allows easy retrieval of already-generated images
 234          *  using the LaTeX snippet as the identifier.
 235          */
 236         typedef shared_ptr<PreviewImage> PreviewImagePtr;
 237         ///
 238         typedef map<string, PreviewImagePtr> Cache;
 239         ///
 240         Cache cache_;
 241
 242         /** pending_ stores the LaTeX snippets in anticipation of them being
 243          *  sent to the converter.
 244          */
 245         PendingSnippets pending_;
 246
 247         /** in_progress_ stores all forked processes so that we can proceed
 248          *  thereafter.
 249             The map uses the conversion commands as its identifiers.
 250          */
 251         InProgressProcesses in_progress_;
 252
 253         ///
 254         set<docstring> macrodefs_;
 255
 256         ///
 257         PreviewLoader & parent_;
 258         ///
 259         Buffer const & buffer_;
 260         ///
 261         mutable int font_scaling_factor_;
 262         ///
 263         QTimer * delay_refresh_;
 264
 265         /// We don't own this
 266         static lyx::Converter const * pconverter_;
 267 };
 268
 269
 270 lyx::Converter const * PreviewLoader::Impl::pconverter_;
 271
 272
 273 //
 274 // The public interface, defined in PreviewLoader.h
 275 //
 276
 277 PreviewLoader::PreviewLoader(Buffer const & b)
 278         : pimpl_(new Impl(*this, b))
 279 {}
 280
 281
 282 PreviewLoader::~PreviewLoader()
 283 {
 284         delete pimpl_;
 285 }
 286
 287
 288 PreviewImage const * PreviewLoader::preview(string const & latex_snippet) const
 289 {
 290         return pimpl_->preview(latex_snippet);
 291 }
 292
 293
 294 PreviewLoader::Status PreviewLoader::status(string const & latex_snippet) const
 295 {
 296         return pimpl_->status(latex_snippet);
 297 }
 298
 299
 300 void PreviewLoader::add(string const & latex_snippet) const
 301 {
 302         pimpl_->add(latex_snippet);
 303 }
 304
 305
 306 void PreviewLoader::remove(string const & latex_snippet) const
 307 {
 308         pimpl_->remove(latex_snippet);
 309 }
 310
 311
 312 void PreviewLoader::addMacroDef(docstring const & latex_snippet) const
 313 {
 314         pimpl_->addMacroDef(latex_snippet);
 315 }
 316
 317
 318 bool PreviewLoader::hasMacroDef(docstring const & latex_snippet) const
 319 {
 320         return pimpl_->hasMacroDef(latex_snippet);
 321 }
 322
 323
 324 void PreviewLoader::startLoading(bool wait) const
 325 {
 326         pimpl_->startLoading(wait);
 327 }
 328
 329
 330 void PreviewLoader::refreshPreviews()
 331 {
 332         pimpl_->refreshPreviews();
 333 }
 334
 335
 336 boost::signals::connection PreviewLoader::connect(slot_type const & slot) const
 337 {
 338         return pimpl_->imageReady.connect(slot);
 339 }
 340
 341
 342 void PreviewLoader::emitSignal(PreviewImage const & pimage) const
 343 {
 344         pimpl_->imageReady(pimage);
 345 }
 346
 347
 348 Buffer const & PreviewLoader::buffer() const
 349 {
 350         return pimpl_->buffer();
 351 }
 352
 353 } // namespace graphics
 354 } // namespace lyx
 355
 356
 357 // The details of the Impl
 358 // =======================
 359
 360 namespace {
 361
 362 class IncrementedFileName {
 363 public:
 364         IncrementedFileName(string const & to_format,
 365                             string const & filename_base)
 366                 : to_format_(to_format), base_(filename_base), counter_(1)
 367         {}
 368
 369         SnippetPair const operator()(string const & snippet)
 370         {
 371                 ostringstream os;
 372                 os << base_ << counter_++ << '.' << to_format_;
 373                 string const file = os.str();
 374
 375                 return make_pair(snippet, FileName(file));
 376         }
 377
 378 private:
 379         string const & to_format_;
 380         string const & base_;
 381         int counter_;
 382 };
 383
 384
 385 InProgress::InProgress(string const & filename_base,
 386                        PendingSnippets const & pending,
 387                        string const & to_format)
 388         : pid(0),
 389           metrics_file(filename_base + ".metrics"),
 390           snippets(pending.size())
 391 {
 392         PendingSnippets::const_iterator pit  = pending.begin();
 393         PendingSnippets::const_iterator pend = pending.end();
 394         BitmapFile::iterator sit = snippets.begin();
 395
 396         transform(pit, pend, sit,
 397                        IncrementedFileName(to_format, filename_base));
 398 }
 399
 400
 401 void InProgress::stop() const
 402 {
 403         if (pid)
 404                 ForkedCallsController::kill(pid, 0);
 405
 406         if (!metrics_file.empty())
 407                 metrics_file.removeFile();
 408
 409         BitmapFile::const_iterator vit  = snippets.begin();
 410         BitmapFile::const_iterator vend = snippets.end();
 411         for (; vit != vend; ++vit) {
 412                 if (!vit->second.empty())
 413                         vit->second.removeFile();
 414         }
 415 }
 416
 417 } // namespace anon
 418
 419
 420 namespace lyx {
 421 namespace graphics {
 422
 423 PreviewLoader::Impl::Impl(PreviewLoader & p, Buffer const & b)
 424         : parent_(p), buffer_(b)
 425 {
 426         font_scaling_factor_ = int(buffer_.fontScalingFactor());
 427         if (!pconverter_)
 428                 pconverter_ = setConverter("lyxpreview");
 429
 430         delay_refresh_ = new QTimer(&parent_);
 431         delay_refresh_->setSingleShot(true);
 432         QObject::connect(delay_refresh_, SIGNAL(timeout()),
 433                          &parent_, SLOT(refreshPreviews()));
 434 }
 435
 436
 437 PreviewLoader::Impl::~Impl()
 438 {
 439         InProgressProcesses::iterator ipit  = in_progress_.begin();
 440         InProgressProcesses::iterator ipend = in_progress_.end();
 441
 442         for (; ipit != ipend; ++ipit)
 443                 ipit->second.stop();
 444 }
 445
 446
 447 PreviewImage const *
 448 PreviewLoader::Impl::preview(string const & latex_snippet) const
 449 {
 450         int fs = int(buffer_.fontScalingFactor());
 451         if (font_scaling_factor_ != fs) {
 452                 // Schedule refresh of all previews on zoom changes.
 453                 // The previews are regenerated only after the zoom factor
 454                 // has not been changed for about 1 second.
 455                 delay_refresh_->start(1000);
 456         }
 457         // Don't try to access the cache until we are finished.
 458         if (delay_refresh_->isActive())
 459                 return 0;
 460         Cache::const_iterator it = cache_.find(latex_snippet);
 461         return (it == cache_.end()) ? 0 : it->second.get();
 462 }
 463
 464
 465 void PreviewLoader::Impl::refreshPreviews()
 466 {
 467         font_scaling_factor_ = int(buffer_.fontScalingFactor());
 468         Cache::const_iterator cit = cache_.begin();
 469         Cache::const_iterator cend = cache_.end();
 470         while (cit != cend)
 471                 parent_.remove((cit++)->first);
 472         buffer_.updatePreviews();
 473 }
 474
 475
 476 namespace {
 477
 478 class FindSnippet {
 479 public:
 480         FindSnippet(string const & s) : snippet_(s) {}
 481         bool operator()(InProgressProcess const & process) const
 482         {
 483                 BitmapFile const & snippets = process.second.snippets;
 484                 BitmapFile::const_iterator beg  = snippets.begin();
 485                 BitmapFile::const_iterator end = snippets.end();
 486                 return find_if(beg, end, FindFirst(snippet_)) != end;
 487         }
 488
 489 private:
 490         string const snippet_;
 491 };
 492
 493 } // namespace anon
 494
 495 PreviewLoader::Status
 496 PreviewLoader::Impl::status(string const & latex_snippet) const
 497 {
 498         Cache::const_iterator cit = cache_.find(latex_snippet);
 499         if (cit != cache_.end())
 500                 return Ready;
 501
 502         PendingSnippets::const_iterator pit  = pending_.begin();
 503         PendingSnippets::const_iterator pend = pending_.end();
 504
 505         pit = find(pit, pend, latex_snippet);
 506         if (pit != pend)
 507                 return InQueue;
 508
 509         InProgressProcesses::const_iterator ipit  = in_progress_.begin();
 510         InProgressProcesses::const_iterator ipend = in_progress_.end();
 511
 512         ipit = find_if(ipit, ipend, FindSnippet(latex_snippet));
 513         if (ipit != ipend)
 514                 return Processing;
 515
 516         return NotFound;
 517 }
 518
 519
 520 void PreviewLoader::Impl::add(string const & latex_snippet)
 521 {
 522         if (!pconverter_ || status(latex_snippet) != NotFound)
 523                 return;
 524
 525         string const snippet = trim(latex_snippet);
 526         if (snippet.empty())
 527                 return;
 528
 529         LYXERR(Debug::GRAPHICS, "adding snippet:\n" << snippet);
 530
 531         pending_.push_back(snippet);
 532 }
 533
 534
 535 namespace {
 536
 537 class EraseSnippet {
 538 public:
 539         EraseSnippet(string const & s) : snippet_(s) {}
 540         void operator()(InProgressProcess & process)
 541         {
 542                 BitmapFile & snippets = process.second.snippets;
 543                 BitmapFile::iterator it  = snippets.begin();
 544                 BitmapFile::iterator end = snippets.end();
 545
 546                 it = find_if(it, end, FindFirst(snippet_));
 547                 if (it != end)
 548                         snippets.erase(it, it+1);
 549         }
 550
 551 private:
 552         string const & snippet_;
 553 };
 554
 555 } // namespace anon
 556
 557
 558 void PreviewLoader::Impl::remove(string const & latex_snippet)
 559 {
 560         Cache::iterator cit = cache_.find(latex_snippet);
 561         if (cit != cache_.end())
 562                 cache_.erase(cit);
 563
 564         PendingSnippets::iterator pit  = pending_.begin();
 565         PendingSnippets::iterator pend = pending_.end();
 566
 567         pending_.erase(std::remove(pit, pend, latex_snippet), pend);
 568
 569         InProgressProcesses::iterator ipit  = in_progress_.begin();
 570         InProgressProcesses::iterator ipend = in_progress_.end();
 571
 572         for_each(ipit, ipend, EraseSnippet(latex_snippet));
 573
 574         while (ipit != ipend) {
 575                 InProgressProcesses::iterator curr = ipit++;
 576                 if (curr->second.snippets.empty())
 577                         in_progress_.erase(curr);
 578         }
 579 }
 580
 581
 582 void PreviewLoader::Impl::addMacroDef(docstring const & latex_snippet)
 583 {
 584         macrodefs_.insert(latex_snippet);
 585 }
 586
 587
 588 bool PreviewLoader::Impl::hasMacroDef(docstring const & latex_snippet) const
 589 {
 590         return macrodefs_.find(latex_snippet) != macrodefs_.end();
 591 }
 592
 593
 594 void PreviewLoader::Impl::startLoading(bool wait)
 595 {
 596         if (pending_.empty() || !pconverter_)
 597                 return;
 598
 599         // Only start the process off after the buffer is loaded from file.
 600         if (!buffer_.isFullyLoaded())
 601                 return;
 602
 603         LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()");
 604
 605         // As used by the LaTeX file and by the resulting image files
 606         FileName const directory(buffer_.temppath());
 607
 608         FileName const latexfile = unique_tex_filename(directory);
 609         string const filename_base = removeExtension(latexfile.absFileName());
 610
 611         // Create an InProgress instance to place in the map of all
 612         // such processes if it starts correctly.
 613         InProgress inprogress(filename_base, pending_, pconverter_->to());
 614
 615         // clear pending_, so we're ready to start afresh.
 616         pending_.clear();
 617
 618         // Output the LaTeX file.
 619         // we use the encoding of the buffer
 620         Encoding const & enc = buffer_.params().encoding();
 621         ofdocstream of;
 622         try { of.reset(enc.iconvName()); }
 623         catch (iconv_codecvt_facet_exception const & e) {
 624                 LYXERR0("Caught iconv exception: " << e.what()
 625                         << "\nUnable to create LaTeX file: " << latexfile);
 626                 return;
 627         }
 628
 629         TexRow texrow;
 630         otexstream os(of, texrow);
 631         OutputParams runparams(&enc);
 632         LaTeXFeatures features(buffer_, buffer_.params(), runparams);
 633
 634         if (!openFileWrite(of, latexfile))
 635                 return;
 636
 637         if (!of) {
 638                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 639                                         << "Unable to create LaTeX file\n" << latexfile);
 640                 return;
 641         }
 642         of << "\\batchmode\n";
 643
 644         LYXERR(Debug::LATEX, "Format = " << buffer_.params().getDefaultOutputFormat());
 645         string latexparam = "";
 646         bool docformat = !buffer_.params().default_output_format.empty()
 647                         && buffer_.params().default_output_format != "default";
 648         // Use LATEX flavor if the document does not specify a specific
 649         // output format (see bug 9371).
 650         OutputParams::FLAVOR flavor = docformat
 651                                         ? buffer_.params().getOutputFlavor()
 652                                         : OutputParams::LATEX;
 653         if (buffer_.params().encoding().package() == Encoding::japanese) {
 654                 latexparam = " --latex=platex";
 655                 flavor = OutputParams::LATEX;
 656         }
 657         else if (buffer_.params().useNonTeXFonts) {
 658                 if (flavor == OutputParams::LUATEX)
 659                         latexparam = " --latex=lualatex";
 660                 else {
 661                         flavor = OutputParams::XETEX;
 662                         latexparam = " --latex=xelatex";
 663                 }
 664         }
 665         else {
 666                 switch (flavor) {
 667                         case OutputParams::PDFLATEX:
 668                                 latexparam = " --latex=pdflatex";
 669                                 break;
 670                         case OutputParams::XETEX:
 671                                 latexparam = " --latex=xelatex";
 672                                 break;
 673                         case OutputParams::LUATEX:
 674                                 latexparam = " --latex=lualatex";
 675                                 break;
 676                         case OutputParams::DVILUATEX:
 677                                 latexparam = " --latex=dvilualatex";
 678                                 break;
 679                         default:
 680                                 flavor = OutputParams::LATEX;
 681                 }
 682         }
 683         dumpPreamble(os, flavor);
 684         // handle inputenc etc.
 685         // I think, this is already hadled by dumpPreamble(): Kornel
 686         // buffer_.params().writeEncodingPreamble(os, features);
 687         of << "\n\\begin{document}\n";
 688         dumpData(of, inprogress.snippets);
 689         of << "\n\\end{document}\n";
 690         of.close();
 691         if (of.fail()) {
 692                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 693                                          << "File was not closed properly.");
 694                 return;
 695         }
 696
 697         // The conversion command.
 698         ostringstream cs;
 699         cs << pconverter_->command()
 700            << " " << quoteName(latexfile.toFilesystemEncoding())
 701            << " --dpi " << font_scaling_factor_;
 702
 703         // FIXME XHTML
 704         // The colors should be customizable.
 705         if (!buffer_.isExporting()) {
 706                 ColorCode const fg = PreviewLoader::foregroundColor();
 707                 ColorCode const bg = PreviewLoader::backgroundColor();
 708                 cs << " --fg " << theApp()->hexName(fg)
 709                    << " --bg " << theApp()->hexName(bg);
 710         }
 711
 712         cs << latexparam;
 713         if (buffer_.params().bibtex_command != "default")
 714                 cs << " --bibtex=" << quoteName(buffer_.params().bibtex_command);
 715         else if (buffer_.params().encoding().package() == Encoding::japanese)
 716                 cs << " --bibtex=" << quoteName(lyxrc.jbibtex_command);
 717         else
 718                 cs << " --bibtex=" << quoteName(lyxrc.bibtex_command);
 719         if (buffer_.params().bufferFormat() == "lilypond-book")
 720                 cs << " --lilypond";
 721
 722         string const command = cs.str();
 723
 724         if (wait) {
 725                 ForkedCall call(buffer_.filePath(), buffer_.layoutPos());
 726                 int ret = call.startScript(ForkedProcess::Wait, command);
 727                 // FIXME THREAD
 728                 static int fake = (2^20) + 1;
 729                 int pid = fake++;
 730                 inprogress.pid = pid;
 731                 inprogress.command = command;
 732                 in_progress_[pid] = inprogress;
 733                 finishedGenerating(pid, ret);
 734                 return;
 735         }
 736
 737         // Initiate the conversion from LaTeX to bitmap images files.
 738         ForkedCall::SignalTypePtr
 739                 convert_ptr(new ForkedCall::SignalType);
 740         convert_ptr->connect(bind(&Impl::finishedGenerating, this, _1, _2));
 741
 742         ForkedCall call(buffer_.filePath());
 743         int ret = call.startScript(command, convert_ptr);
 744
 745         if (ret != 0) {
 746                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 747                                         << "Unable to start process\n" << command);
 748                 return;
 749         }
 750
 751         // Store the generation process in a list of all such processes
 752         inprogress.pid = call.pid();
 753         inprogress.command = command;
 754         in_progress_[inprogress.pid] = inprogress;
 755 }
 756
 757
 758 double PreviewLoader::displayPixelRatio() const
 759 {
 760         return buffer().params().display_pixel_ratio;
 761 }
 762
 763 void PreviewLoader::Impl::finishedGenerating(pid_t pid, int retval)
 764 {
 765         // Paranoia check!
 766         InProgressProcesses::iterator git = in_progress_.find(pid);
 767         if (git == in_progress_.end()) {
 768                 lyxerr << "PreviewLoader::finishedGenerating(): unable to find "
 769                         "data for PID " << pid << endl;
 770                 return;
 771         }
 772
 773         string const command = git->second.command;
 774         string const status = retval > 0 ? "failed" : "succeeded";
 775         LYXERR(Debug::GRAPHICS, "PreviewLoader::finishedInProgress("
 776                                 << retval << "): processing " << status
 777                                 << " for " << command);
 778         if (retval > 0)
 779                 return;
 780
 781         // Read the metrics file, if it exists
 782         vector<double> ascent_fractions(git->second.snippets.size());
 783         setAscentFractions(ascent_fractions, git->second.metrics_file);
 784
 785         // Add these newly generated bitmap files to the cache and
 786         // start loading them into LyX.
 787         BitmapFile::const_iterator it  = git->second.snippets.begin();
 788         BitmapFile::const_iterator end = git->second.snippets.end();
 789
 790         list<PreviewImagePtr> newimages;
 791
 792         int metrics_counter = 0;
 793         for (; it != end; ++it, ++metrics_counter) {
 794                 string const & snip = it->first;
 795                 FileName const & file = it->second;
 796                 double af = ascent_fractions[metrics_counter];
 797
 798                 // Add the image to the cache only if it's actually present
 799                 // and not empty (an empty image is signaled by af < 0)
 800                 if (af >= 0 && file.isReadableFile()) {
 801                         PreviewImagePtr ptr(new PreviewImage(parent_, snip, file, af));
 802                         cache_[snip] = ptr;
 803
 804                         newimages.push_back(ptr);
 805                 }
 806
 807         }
 808
 809         // Remove the item from the list of still-executing processes.
 810         in_progress_.erase(git);
 811
 812         // Tell the outside world
 813         list<PreviewImagePtr>::const_reverse_iterator
 814                 nit  = newimages.rbegin();
 815         list<PreviewImagePtr>::const_reverse_iterator
 816                 nend = newimages.rend();
 817         for (; nit != nend; ++nit) {
 818                 imageReady(*nit->get());
 819         }
 820 }
 821
 822
 823 void PreviewLoader::Impl::dumpPreamble(otexstream & os, OutputParams::FLAVOR flavor) const
 824 {
 825         // Dump the preamble only.
 826         LYXERR(Debug::LATEX, "dumpPreamble, flavor == " << flavor);
 827         OutputParams runparams(&buffer_.params().encoding());
 828         runparams.flavor = flavor;
 829         runparams.nice = true;
 830         runparams.moving_arg = true;
 831         runparams.free_spacing = true;
 832         runparams.is_child = buffer_.parent();
 833         buffer_.writeLaTeXSource(os, buffer_.filePath(), runparams, Buffer::OnlyPreamble);
 834
 835         // FIXME! This is a HACK! The proper fix is to control the 'true'
 836         // passed to WriteStream below:
 837         // int InsetMathNest::latex(Buffer const &, odocstream & os,
 838         //                          OutputParams const & runparams) const
 839         // {
 840         //      WriteStream wi(os, runparams.moving_arg, true);
 841         //      par_->write(wi);
 842         //      return wi.line();
 843         // }
 844         os << "\n"
 845            << "\\def\\lyxlock{}\n"
 846            << "\n";
 847
 848         // All equation labels appear as "(#)" + preview.sty's rendering of
 849         // the label name
 850         if (lyxrc.preview_hashed_labels)
 851                 os << "\\renewcommand{\\theequation}{\\#}\n";
 852
 853         // Use the preview style file to ensure that each snippet appears on a
 854         // fresh page.
 855         // Also support PDF output (automatically generated e.g. when
 856         // \usepackage[pdftex]{hyperref} is used and XeTeX.
 857         os << "\n"
 858            << "\\usepackage[active,delayed,showlabels,lyx]{preview}\n"
 859            << "\n";
 860 }
 861
 862
 863 void PreviewLoader::Impl::dumpData(odocstream & os,
 864                                    BitmapFile const & vec) const
 865 {
 866         if (vec.empty())
 867                 return;
 868
 869         BitmapFile::const_iterator it  = vec.begin();
 870         BitmapFile::const_iterator end = vec.end();
 871
 872         for (; it != end; ++it) {
 873                 // FIXME UNICODE
 874                 os << "\\begin{preview}\n"
 875                    << from_utf8(it->first)
 876                    << "\n\\end{preview}\n\n";
 877         }
 878 }
 879
 880 } // namespace graphics
 881 } // namespace lyx
 882
 883 #include "moc_PreviewLoader.cpp"