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         /// \p wait whether to wait for the process to complete or, instead,
 211         /// to do it in the background.
 212         void startLoading(bool wait = false);
 213         ///
 214         void refreshPreviews();
 215
 216         /// Emit this signal when an image is ready for display.
 217         boost::signal<void(PreviewImage const &)> imageReady;
 218
 219         Buffer const & buffer() const { return buffer_; }
 220
 221 private:
 222         /// Called by the ForkedCall process that generated the bitmap files.
 223         void finishedGenerating(pid_t, int);
 224         ///
 225         void dumpPreamble(otexstream &, OutputParams::FLAVOR) const;
 226         ///
 227         void dumpData(odocstream &, BitmapFile const &) const;
 228
 229         /** cache_ allows easy retrieval of already-generated images
 230          *  using the LaTeX snippet as the identifier.
 231          */
 232         typedef shared_ptr<PreviewImage> PreviewImagePtr;
 233         ///
 234         typedef map<string, PreviewImagePtr> Cache;
 235         ///
 236         Cache cache_;
 237
 238         /** pending_ stores the LaTeX snippets in anticipation of them being
 239          *  sent to the converter.
 240          */
 241         PendingSnippets pending_;
 242
 243         /** in_progress_ stores all forked processes so that we can proceed
 244          *  thereafter.
 245             The map uses the conversion commands as its identifiers.
 246          */
 247         InProgressProcesses in_progress_;
 248
 249         ///
 250         PreviewLoader & parent_;
 251         ///
 252         Buffer const & buffer_;
 253         ///
 254         mutable int font_scaling_factor_;
 255         ///
 256         QTimer * delay_refresh_;
 257
 258         /// We don't own this
 259         static lyx::Converter const * pconverter_;
 260 };
 261
 262
 263 lyx::Converter const * PreviewLoader::Impl::pconverter_;
 264
 265
 266 //
 267 // The public interface, defined in PreviewLoader.h
 268 //
 269
 270 PreviewLoader::PreviewLoader(Buffer const & b)
 271         : pimpl_(new Impl(*this, b))
 272 {}
 273
 274
 275 PreviewLoader::~PreviewLoader()
 276 {
 277         delete pimpl_;
 278 }
 279
 280
 281 PreviewImage const * PreviewLoader::preview(string const & latex_snippet) const
 282 {
 283         return pimpl_->preview(latex_snippet);
 284 }
 285
 286
 287 PreviewLoader::Status PreviewLoader::status(string const & latex_snippet) const
 288 {
 289         return pimpl_->status(latex_snippet);
 290 }
 291
 292
 293 void PreviewLoader::add(string const & latex_snippet) const
 294 {
 295         pimpl_->add(latex_snippet);
 296 }
 297
 298
 299 void PreviewLoader::remove(string const & latex_snippet) const
 300 {
 301         pimpl_->remove(latex_snippet);
 302 }
 303
 304
 305 void PreviewLoader::startLoading(bool wait) const
 306 {
 307         pimpl_->startLoading(wait);
 308 }
 309
 310
 311 void PreviewLoader::refreshPreviews()
 312 {
 313         pimpl_->refreshPreviews();
 314 }
 315
 316
 317 boost::signals::connection PreviewLoader::connect(slot_type const & slot) const
 318 {
 319         return pimpl_->imageReady.connect(slot);
 320 }
 321
 322
 323 void PreviewLoader::emitSignal(PreviewImage const & pimage) const
 324 {
 325         pimpl_->imageReady(pimage);
 326 }
 327
 328
 329 Buffer const & PreviewLoader::buffer() const
 330 {
 331         return pimpl_->buffer();
 332 }
 333
 334 } // namespace graphics
 335 } // namespace lyx
 336
 337
 338 // The details of the Impl
 339 // =======================
 340
 341 namespace {
 342
 343 class IncrementedFileName {
 344 public:
 345         IncrementedFileName(string const & to_format,
 346                             string const & filename_base)
 347                 : to_format_(to_format), base_(filename_base), counter_(1)
 348         {}
 349
 350         SnippetPair const operator()(string const & snippet)
 351         {
 352                 ostringstream os;
 353                 os << base_ << counter_++ << '.' << to_format_;
 354                 string const file = os.str();
 355
 356                 return make_pair(snippet, FileName(file));
 357         }
 358
 359 private:
 360         string const & to_format_;
 361         string const & base_;
 362         int counter_;
 363 };
 364
 365
 366 InProgress::InProgress(string const & filename_base,
 367                        PendingSnippets const & pending,
 368                        string const & to_format)
 369         : pid(0),
 370           metrics_file(filename_base + ".metrics"),
 371           snippets(pending.size())
 372 {
 373         PendingSnippets::const_iterator pit  = pending.begin();
 374         PendingSnippets::const_iterator pend = pending.end();
 375         BitmapFile::iterator sit = snippets.begin();
 376
 377         transform(pit, pend, sit,
 378                        IncrementedFileName(to_format, filename_base));
 379 }
 380
 381
 382 void InProgress::stop() const
 383 {
 384         if (pid)
 385                 ForkedCallsController::kill(pid, 0);
 386
 387         if (!metrics_file.empty())
 388                 metrics_file.removeFile();
 389
 390         BitmapFile::const_iterator vit  = snippets.begin();
 391         BitmapFile::const_iterator vend = snippets.end();
 392         for (; vit != vend; ++vit) {
 393                 if (!vit->second.empty())
 394                         vit->second.removeFile();
 395         }
 396 }
 397
 398 } // namespace anon
 399
 400
 401 namespace lyx {
 402 namespace graphics {
 403
 404 PreviewLoader::Impl::Impl(PreviewLoader & p, Buffer const & b)
 405         : parent_(p), buffer_(b)
 406 {
 407         font_scaling_factor_ = int(buffer_.fontScalingFactor());
 408         if (!pconverter_)
 409                 pconverter_ = setConverter("lyxpreview");
 410
 411         delay_refresh_ = new QTimer(&parent_);
 412         delay_refresh_->setSingleShot(true);
 413         QObject::connect(delay_refresh_, SIGNAL(timeout()),
 414                          &parent_, SLOT(refreshPreviews()));
 415 }
 416
 417
 418 PreviewLoader::Impl::~Impl()
 419 {
 420         delete delay_refresh_;
 421
 422         InProgressProcesses::iterator ipit  = in_progress_.begin();
 423         InProgressProcesses::iterator ipend = in_progress_.end();
 424
 425         for (; ipit != ipend; ++ipit)
 426                 ipit->second.stop();
 427 }
 428
 429
 430 PreviewImage const *
 431 PreviewLoader::Impl::preview(string const & latex_snippet) const
 432 {
 433         int fs = int(buffer_.fontScalingFactor());
 434         if (font_scaling_factor_ != fs) {
 435                 // Schedule refresh of all previews on zoom changes.
 436                 // The previews are regenerated only after the zoom factor
 437                 // has not been changed for about 1 second.
 438                 delay_refresh_->start(1000);
 439         }
 440         // Don't try to access the cache until we are finished.
 441         if (delay_refresh_->isActive())
 442                 return 0;
 443         Cache::const_iterator it = cache_.find(latex_snippet);
 444         return (it == cache_.end()) ? 0 : it->second.get();
 445 }
 446
 447
 448 void PreviewLoader::Impl::refreshPreviews()
 449 {
 450         font_scaling_factor_ = int(buffer_.fontScalingFactor());
 451         Cache::const_iterator cit = cache_.begin();
 452         Cache::const_iterator cend = cache_.end();
 453         while (cit != cend)
 454                 parent_.remove((cit++)->first);
 455         buffer_.updatePreviews();
 456 }
 457
 458
 459 namespace {
 460
 461 class FindSnippet {
 462 public:
 463         FindSnippet(string const & s) : snippet_(s) {}
 464         bool operator()(InProgressProcess const & process) const
 465         {
 466                 BitmapFile const & snippets = process.second.snippets;
 467                 BitmapFile::const_iterator beg  = snippets.begin();
 468                 BitmapFile::const_iterator end = snippets.end();
 469                 return find_if(beg, end, FindFirst(snippet_)) != end;
 470         }
 471
 472 private:
 473         string const snippet_;
 474 };
 475
 476 } // namespace anon
 477
 478 PreviewLoader::Status
 479 PreviewLoader::Impl::status(string const & latex_snippet) const
 480 {
 481         Cache::const_iterator cit = cache_.find(latex_snippet);
 482         if (cit != cache_.end())
 483                 return Ready;
 484
 485         PendingSnippets::const_iterator pit  = pending_.begin();
 486         PendingSnippets::const_iterator pend = pending_.end();
 487
 488         pit = find(pit, pend, latex_snippet);
 489         if (pit != pend)
 490                 return InQueue;
 491
 492         InProgressProcesses::const_iterator ipit  = in_progress_.begin();
 493         InProgressProcesses::const_iterator ipend = in_progress_.end();
 494
 495         ipit = find_if(ipit, ipend, FindSnippet(latex_snippet));
 496         if (ipit != ipend)
 497                 return Processing;
 498
 499         return NotFound;
 500 }
 501
 502
 503 void PreviewLoader::Impl::add(string const & latex_snippet)
 504 {
 505         if (!pconverter_ || status(latex_snippet) != NotFound)
 506                 return;
 507
 508         string const snippet = trim(latex_snippet);
 509         if (snippet.empty())
 510                 return;
 511
 512         LYXERR(Debug::GRAPHICS, "adding snippet:\n" << snippet);
 513
 514         pending_.push_back(snippet);
 515 }
 516
 517
 518 namespace {
 519
 520 class EraseSnippet {
 521 public:
 522         EraseSnippet(string const & s) : snippet_(s) {}
 523         void operator()(InProgressProcess & process)
 524         {
 525                 BitmapFile & snippets = process.second.snippets;
 526                 BitmapFile::iterator it  = snippets.begin();
 527                 BitmapFile::iterator end = snippets.end();
 528
 529                 it = find_if(it, end, FindFirst(snippet_));
 530                 if (it != end)
 531                         snippets.erase(it, it+1);
 532         }
 533
 534 private:
 535         string const & snippet_;
 536 };
 537
 538 } // namespace anon
 539
 540
 541 void PreviewLoader::Impl::remove(string const & latex_snippet)
 542 {
 543         Cache::iterator cit = cache_.find(latex_snippet);
 544         if (cit != cache_.end())
 545                 cache_.erase(cit);
 546
 547         PendingSnippets::iterator pit  = pending_.begin();
 548         PendingSnippets::iterator pend = pending_.end();
 549
 550         pending_.erase(std::remove(pit, pend, latex_snippet), pend);
 551
 552         InProgressProcesses::iterator ipit  = in_progress_.begin();
 553         InProgressProcesses::iterator ipend = in_progress_.end();
 554
 555         for_each(ipit, ipend, EraseSnippet(latex_snippet));
 556
 557         while (ipit != ipend) {
 558                 InProgressProcesses::iterator curr = ipit++;
 559                 if (curr->second.snippets.empty())
 560                         in_progress_.erase(curr);
 561         }
 562 }
 563
 564
 565 void PreviewLoader::Impl::startLoading(bool wait)
 566 {
 567         if (pending_.empty() || !pconverter_)
 568                 return;
 569
 570         // Only start the process off after the buffer is loaded from file.
 571         if (!buffer_.isFullyLoaded())
 572                 return;
 573
 574         LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()");
 575
 576         // As used by the LaTeX file and by the resulting image files
 577         FileName const directory(buffer_.temppath());
 578
 579         FileName const latexfile = unique_tex_filename(directory);
 580         string const filename_base = removeExtension(latexfile.absFileName());
 581
 582         // Create an InProgress instance to place in the map of all
 583         // such processes if it starts correctly.
 584         InProgress inprogress(filename_base, pending_, pconverter_->to());
 585
 586         // clear pending_, so we're ready to start afresh.
 587         pending_.clear();
 588
 589         // Output the LaTeX file.
 590         // we use the encoding of the buffer
 591         Encoding const & enc = buffer_.params().encoding();
 592         ofdocstream of;
 593         try { of.reset(enc.iconvName()); }
 594         catch (iconv_codecvt_facet_exception const & e) {
 595                 LYXERR0("Caught iconv exception: " << e.what()
 596                         << "\nUnable to create LaTeX file: " << latexfile);
 597                 return;
 598         }
 599
 600         TexRow texrow;
 601         otexstream os(of, texrow);
 602         OutputParams runparams(&enc);
 603         LaTeXFeatures features(buffer_, buffer_.params(), runparams);
 604
 605         if (!openFileWrite(of, latexfile))
 606                 return;
 607
 608         if (!of) {
 609                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 610                                         << "Unable to create LaTeX file\n" << latexfile);
 611                 return;
 612         }
 613         of << "\\batchmode\n";
 614
 615         LYXERR(Debug::LATEX, "Format = " << buffer_.params().getDefaultOutputFormat());
 616         string latexparam = "";
 617         bool docformat = !buffer_.params().default_output_format.empty()
 618                         && buffer_.params().default_output_format != "default";
 619         // Use LATEX flavor if the document does not specify a specific
 620         // output format (see bug 9371).
 621         OutputParams::FLAVOR flavor = docformat
 622                                         ? buffer_.params().getOutputFlavor()
 623                                         : OutputParams::LATEX;
 624         if (buffer_.params().encoding().package() == Encoding::japanese) {
 625                 latexparam = " --latex=platex";
 626                 flavor = OutputParams::LATEX;
 627         }
 628         else if (buffer_.params().useNonTeXFonts) {
 629                 if (flavor == OutputParams::LUATEX)
 630                         latexparam = " --latex=lualatex";
 631                 else {
 632                         flavor = OutputParams::XETEX;
 633                         latexparam = " --latex=xelatex";
 634                 }
 635         }
 636         else {
 637                 switch (flavor) {
 638                         case OutputParams::PDFLATEX:
 639                                 latexparam = " --latex=pdflatex";
 640                                 break;
 641                         case OutputParams::XETEX:
 642                                 latexparam = " --latex=xelatex";
 643                                 break;
 644                         case OutputParams::LUATEX:
 645                                 latexparam = " --latex=lualatex";
 646                                 break;
 647                         case OutputParams::DVILUATEX:
 648                                 latexparam = " --latex=dvilualatex";
 649                                 break;
 650                         default:
 651                                 flavor = OutputParams::LATEX;
 652                 }
 653         }
 654         dumpPreamble(os, flavor);
 655         // handle inputenc etc.
 656         // I think, this is already hadled by dumpPreamble(): Kornel
 657         // buffer_.params().writeEncodingPreamble(os, features);
 658         of << "\n\\begin{document}\n";
 659         dumpData(of, inprogress.snippets);
 660         of << "\n\\end{document}\n";
 661         of.close();
 662         if (of.fail()) {
 663                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 664                                          << "File was not closed properly.");
 665                 return;
 666         }
 667
 668         // The conversion command.
 669         ostringstream cs;
 670         cs << pconverter_->command()
 671            << " " << quoteName(latexfile.toFilesystemEncoding())
 672            << " --dpi " << font_scaling_factor_;
 673
 674         // FIXME XHTML
 675         // The colors should be customizable.
 676         if (!buffer_.isExporting()) {
 677                 ColorCode const fg = PreviewLoader::foregroundColor();
 678                 ColorCode const bg = PreviewLoader::backgroundColor();
 679                 cs << " --fg " << theApp()->hexName(fg)
 680                    << " --bg " << theApp()->hexName(bg);
 681         }
 682
 683         cs << latexparam;
 684         if (buffer_.params().bibtex_command != "default")
 685                 cs << " --bibtex=" << quoteName(buffer_.params().bibtex_command);
 686         else if (buffer_.params().encoding().package() == Encoding::japanese)
 687                 cs << " --bibtex=" << quoteName(lyxrc.jbibtex_command);
 688         else
 689                 cs << " --bibtex=" << quoteName(lyxrc.bibtex_command);
 690         if (buffer_.params().bufferFormat() == "lilypond-book")
 691                 cs << " --lilypond";
 692
 693         string const command = cs.str();
 694
 695         if (wait) {
 696                 ForkedCall call(buffer_.filePath(), buffer_.layoutPos());
 697                 int ret = call.startScript(ForkedProcess::Wait, command);
 698                 // FIXME THREAD
 699                 static int fake = (2^20) + 1;
 700                 int pid = fake++;
 701                 inprogress.pid = pid;
 702                 inprogress.command = command;
 703                 in_progress_[pid] = inprogress;
 704                 finishedGenerating(pid, ret);
 705                 return;
 706         }
 707
 708         // Initiate the conversion from LaTeX to bitmap images files.
 709         ForkedCall::SignalTypePtr
 710                 convert_ptr(new ForkedCall::SignalType);
 711         convert_ptr->connect(bind(&Impl::finishedGenerating, this, _1, _2));
 712
 713         ForkedCall call(buffer_.filePath());
 714         int ret = call.startScript(command, convert_ptr);
 715
 716         if (ret != 0) {
 717                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 718                                         << "Unable to start process\n" << command);
 719                 return;
 720         }
 721
 722         // Store the generation process in a list of all such processes
 723         inprogress.pid = call.pid();
 724         inprogress.command = command;
 725         in_progress_[inprogress.pid] = inprogress;
 726 }
 727
 728
 729 double PreviewLoader::displayPixelRatio() const
 730 {
 731         return buffer().params().display_pixel_ratio;
 732 }
 733
 734 void PreviewLoader::Impl::finishedGenerating(pid_t pid, int retval)
 735 {
 736         // Paranoia check!
 737         InProgressProcesses::iterator git = in_progress_.find(pid);
 738         if (git == in_progress_.end()) {
 739                 lyxerr << "PreviewLoader::finishedGenerating(): unable to find "
 740                         "data for PID " << pid << endl;
 741                 return;
 742         }
 743
 744         string const command = git->second.command;
 745         string const status = retval > 0 ? "failed" : "succeeded";
 746         LYXERR(Debug::GRAPHICS, "PreviewLoader::finishedInProgress("
 747                                 << retval << "): processing " << status
 748                                 << " for " << command);
 749         if (retval > 0)
 750                 return;
 751
 752         // Read the metrics file, if it exists
 753         vector<double> ascent_fractions(git->second.snippets.size());
 754         setAscentFractions(ascent_fractions, git->second.metrics_file);
 755
 756         // Add these newly generated bitmap files to the cache and
 757         // start loading them into LyX.
 758         BitmapFile::const_iterator it  = git->second.snippets.begin();
 759         BitmapFile::const_iterator end = git->second.snippets.end();
 760
 761         list<PreviewImagePtr> newimages;
 762
 763         int metrics_counter = 0;
 764         for (; it != end; ++it, ++metrics_counter) {
 765                 string const & snip = it->first;
 766                 FileName const & file = it->second;
 767                 double af = ascent_fractions[metrics_counter];
 768
 769                 // Add the image to the cache only if it's actually present
 770                 // and not empty (an empty image is signaled by af < 0)
 771                 if (af >= 0 && file.isReadableFile()) {
 772                         PreviewImagePtr ptr(new PreviewImage(parent_, snip, file, af));
 773                         cache_[snip] = ptr;
 774
 775                         newimages.push_back(ptr);
 776                 }
 777
 778         }
 779
 780         // Remove the item from the list of still-executing processes.
 781         in_progress_.erase(git);
 782
 783         // Tell the outside world
 784         list<PreviewImagePtr>::const_reverse_iterator
 785                 nit  = newimages.rbegin();
 786         list<PreviewImagePtr>::const_reverse_iterator
 787                 nend = newimages.rend();
 788         for (; nit != nend; ++nit) {
 789                 imageReady(*nit->get());
 790         }
 791 }
 792
 793
 794 void PreviewLoader::Impl::dumpPreamble(otexstream & os, OutputParams::FLAVOR flavor) const
 795 {
 796         // Dump the preamble only.
 797         LYXERR(Debug::LATEX, "dumpPreamble, flavor == " << flavor);
 798         OutputParams runparams(&buffer_.params().encoding());
 799         runparams.flavor = flavor;
 800         runparams.nice = true;
 801         runparams.moving_arg = true;
 802         runparams.free_spacing = true;
 803         runparams.is_child = buffer_.parent();
 804         buffer_.writeLaTeXSource(os, buffer_.filePath(), runparams, Buffer::OnlyPreamble);
 805
 806         // FIXME! This is a HACK! The proper fix is to control the 'true'
 807         // passed to WriteStream below:
 808         // int InsetMathNest::latex(Buffer const &, odocstream & os,
 809         //                          OutputParams const & runparams) const
 810         // {
 811         //      WriteStream wi(os, runparams.moving_arg, true);
 812         //      par_->write(wi);
 813         //      return wi.line();
 814         // }
 815         os << "\n"
 816            << "\\def\\lyxlock{}\n"
 817            << "\n";
 818
 819         // All equation labels appear as "(#)" + preview.sty's rendering of
 820         // the label name
 821         if (lyxrc.preview_hashed_labels)
 822                 os << "\\renewcommand{\\theequation}{\\#}\n";
 823
 824         // Use the preview style file to ensure that each snippet appears on a
 825         // fresh page.
 826         // Also support PDF output (automatically generated e.g. when
 827         // \usepackage[pdftex]{hyperref} is used and XeTeX.
 828         os << "\n"
 829            << "\\usepackage[active,delayed,showlabels,lyx]{preview}\n"
 830            << "\n";
 831 }
 832
 833
 834 void PreviewLoader::Impl::dumpData(odocstream & os,
 835                                    BitmapFile const & vec) const
 836 {
 837         if (vec.empty())
 838                 return;
 839
 840         BitmapFile::const_iterator it  = vec.begin();
 841         BitmapFile::const_iterator end = vec.end();
 842
 843         for (; it != end; ++it) {
 844                 // FIXME UNICODE
 845                 os << "\\begin{preview}\n"
 846                    << from_utf8(it->first)
 847                    << "\n\\end{preview}\n\n";
 848         }
 849 }
 850
 851 } // namespace graphics
 852 } // namespace lyx
 853
 854 #include "moc_PreviewLoader.cpp"