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         mutable int fg_color_;
 257         ///
 258         mutable int bg_color_;
 259         ///
 260         QTimer * delay_refresh_;
 261         ///
 262         bool finished_generating_;
 263
 264         /// We don't own this
 265         static lyx::Converter const * pconverter_;
 266 };
 267
 268
 269 lyx::Converter const * PreviewLoader::Impl::pconverter_;
 270
 271
 272 //
 273 // The public interface, defined in PreviewLoader.h
 274 //
 275
 276 PreviewLoader::PreviewLoader(Buffer const & b)
 277         : pimpl_(new Impl(*this, b))
 278 {}
 279
 280
 281 PreviewLoader::~PreviewLoader()
 282 {
 283         delete pimpl_;
 284 }
 285
 286
 287 PreviewImage const * PreviewLoader::preview(string const & latex_snippet) const
 288 {
 289         return pimpl_->preview(latex_snippet);
 290 }
 291
 292
 293 PreviewLoader::Status PreviewLoader::status(string const & latex_snippet) const
 294 {
 295         return pimpl_->status(latex_snippet);
 296 }
 297
 298
 299 void PreviewLoader::add(string const & latex_snippet) const
 300 {
 301         pimpl_->add(latex_snippet);
 302 }
 303
 304
 305 void PreviewLoader::remove(string const & latex_snippet) const
 306 {
 307         pimpl_->remove(latex_snippet);
 308 }
 309
 310
 311 void PreviewLoader::startLoading(bool wait) const
 312 {
 313         pimpl_->startLoading(wait);
 314 }
 315
 316
 317 void PreviewLoader::refreshPreviews()
 318 {
 319         pimpl_->refreshPreviews();
 320 }
 321
 322
 323 boost::signals::connection PreviewLoader::connect(slot_type const & slot) const
 324 {
 325         return pimpl_->imageReady.connect(slot);
 326 }
 327
 328
 329 void PreviewLoader::emitSignal(PreviewImage const & pimage) const
 330 {
 331         pimpl_->imageReady(pimage);
 332 }
 333
 334
 335 Buffer const & PreviewLoader::buffer() const
 336 {
 337         return pimpl_->buffer();
 338 }
 339
 340 } // namespace graphics
 341 } // namespace lyx
 342
 343
 344 // The details of the Impl
 345 // =======================
 346
 347 namespace {
 348
 349 class IncrementedFileName {
 350 public:
 351         IncrementedFileName(string const & to_format,
 352                             string const & filename_base)
 353                 : to_format_(to_format), base_(filename_base), counter_(1)
 354         {}
 355
 356         SnippetPair const operator()(string const & snippet)
 357         {
 358                 ostringstream os;
 359                 os << base_ << counter_++ << '.' << to_format_;
 360                 string const file = os.str();
 361
 362                 return make_pair(snippet, FileName(file));
 363         }
 364
 365 private:
 366         string const & to_format_;
 367         string const & base_;
 368         int counter_;
 369 };
 370
 371
 372 InProgress::InProgress(string const & filename_base,
 373                        PendingSnippets const & pending,
 374                        string const & to_format)
 375         : pid(0),
 376           metrics_file(filename_base + ".metrics"),
 377           snippets(pending.size())
 378 {
 379         PendingSnippets::const_iterator pit  = pending.begin();
 380         PendingSnippets::const_iterator pend = pending.end();
 381         BitmapFile::iterator sit = snippets.begin();
 382
 383         transform(pit, pend, sit,
 384                        IncrementedFileName(to_format, filename_base));
 385 }
 386
 387
 388 void InProgress::stop() const
 389 {
 390         if (pid)
 391                 ForkedCallsController::kill(pid, 0);
 392
 393         if (!metrics_file.empty())
 394                 metrics_file.removeFile();
 395
 396         BitmapFile::const_iterator vit  = snippets.begin();
 397         BitmapFile::const_iterator vend = snippets.end();
 398         for (; vit != vend; ++vit) {
 399                 if (!vit->second.empty())
 400                         vit->second.removeFile();
 401         }
 402 }
 403
 404 } // namespace anon
 405
 406
 407 namespace lyx {
 408 namespace graphics {
 409
 410 PreviewLoader::Impl::Impl(PreviewLoader & p, Buffer const & b)
 411         : parent_(p), buffer_(b), finished_generating_(true)
 412 {
 413         font_scaling_factor_ = int(buffer_.fontScalingFactor());
 414         if (theApp()) {
 415                 fg_color_ = strtol(theApp()->hexName(foregroundColor()).c_str(), 0, 16);
 416                 bg_color_ = strtol(theApp()->hexName(backgroundColor()).c_str(), 0, 16);
 417         } else {
 418                 fg_color_ = 0x0;
 419                 bg_color_ = 0xffffff;
 420         }
 421         if (!pconverter_)
 422                 pconverter_ = setConverter("lyxpreview");
 423
 424         delay_refresh_ = new QTimer(&parent_);
 425         delay_refresh_->setSingleShot(true);
 426         QObject::connect(delay_refresh_, SIGNAL(timeout()),
 427                          &parent_, SLOT(refreshPreviews()));
 428 }
 429
 430
 431 PreviewLoader::Impl::~Impl()
 432 {
 433         delete delay_refresh_;
 434
 435         InProgressProcesses::iterator ipit  = in_progress_.begin();
 436         InProgressProcesses::iterator ipend = in_progress_.end();
 437
 438         for (; ipit != ipend; ++ipit)
 439                 ipit->second.stop();
 440 }
 441
 442
 443 PreviewImage const *
 444 PreviewLoader::Impl::preview(string const & latex_snippet) const
 445 {
 446         int fs = int(buffer_.fontScalingFactor());
 447         int fg = 0x0;
 448         int bg = 0xffffff;
 449         if (theApp()) {
 450                 fg = strtol(theApp()->hexName(foregroundColor()).c_str(), 0, 16);
 451                 bg = strtol(theApp()->hexName(backgroundColor()).c_str(), 0, 16);
 452         }
 453         if (font_scaling_factor_ != fs || fg_color_ != fg || bg_color_ != bg) {
 454                 // Schedule refresh of all previews on zoom or color changes.
 455                 // The previews are regenerated only after the zoom factor
 456                 // has not been changed for about 1 second.
 457                 fg_color_ = fg;
 458                 bg_color_ = bg;
 459                 delay_refresh_->start(1000);
 460         }
 461         // Don't try to access the cache until we are done.
 462         if (delay_refresh_->isActive() || !finished_generating_)
 463                 return 0;
 464         Cache::const_iterator it = cache_.find(latex_snippet);
 465         return (it == cache_.end()) ? 0 : it->second.get();
 466 }
 467
 468
 469 void PreviewLoader::Impl::refreshPreviews()
 470 {
 471         font_scaling_factor_ = int(buffer_.fontScalingFactor());
 472         // Reschedule refresh until the previous process completed.
 473         if (!finished_generating_) {
 474                 delay_refresh_->start(1000);
 475                 return;
 476         }
 477         Cache::const_iterator cit = cache_.begin();
 478         Cache::const_iterator cend = cache_.end();
 479         while (cit != cend)
 480                 parent_.remove((cit++)->first);
 481         finished_generating_ = false;
 482         buffer_.updatePreviews();
 483 }
 484
 485
 486 namespace {
 487
 488 class FindSnippet {
 489 public:
 490         FindSnippet(string const & s) : snippet_(s) {}
 491         bool operator()(InProgressProcess const & process) const
 492         {
 493                 BitmapFile const & snippets = process.second.snippets;
 494                 BitmapFile::const_iterator beg  = snippets.begin();
 495                 BitmapFile::const_iterator end = snippets.end();
 496                 return find_if(beg, end, FindFirst(snippet_)) != end;
 497         }
 498
 499 private:
 500         string const snippet_;
 501 };
 502
 503 } // namespace anon
 504
 505 PreviewLoader::Status
 506 PreviewLoader::Impl::status(string const & latex_snippet) const
 507 {
 508         Cache::const_iterator cit = cache_.find(latex_snippet);
 509         if (cit != cache_.end())
 510                 return Ready;
 511
 512         PendingSnippets::const_iterator pit  = pending_.begin();
 513         PendingSnippets::const_iterator pend = pending_.end();
 514
 515         pit = find(pit, pend, latex_snippet);
 516         if (pit != pend)
 517                 return InQueue;
 518
 519         InProgressProcesses::const_iterator ipit  = in_progress_.begin();
 520         InProgressProcesses::const_iterator ipend = in_progress_.end();
 521
 522         ipit = find_if(ipit, ipend, FindSnippet(latex_snippet));
 523         if (ipit != ipend)
 524                 return Processing;
 525
 526         return NotFound;
 527 }
 528
 529
 530 void PreviewLoader::Impl::add(string const & latex_snippet)
 531 {
 532         if (!pconverter_ || status(latex_snippet) != NotFound)
 533                 return;
 534
 535         string const snippet = trim(latex_snippet);
 536         if (snippet.empty())
 537                 return;
 538
 539         LYXERR(Debug::GRAPHICS, "adding snippet:\n" << snippet);
 540
 541         pending_.push_back(snippet);
 542 }
 543
 544
 545 namespace {
 546
 547 class EraseSnippet {
 548 public:
 549         EraseSnippet(string const & s) : snippet_(s) {}
 550         void operator()(InProgressProcess & process)
 551         {
 552                 BitmapFile & snippets = process.second.snippets;
 553                 BitmapFile::iterator it  = snippets.begin();
 554                 BitmapFile::iterator end = snippets.end();
 555
 556                 it = find_if(it, end, FindFirst(snippet_));
 557                 if (it != end)
 558                         snippets.erase(it, it+1);
 559         }
 560
 561 private:
 562         string const & snippet_;
 563 };
 564
 565 } // namespace anon
 566
 567
 568 void PreviewLoader::Impl::remove(string const & latex_snippet)
 569 {
 570         Cache::iterator cit = cache_.find(latex_snippet);
 571         if (cit != cache_.end())
 572                 cache_.erase(cit);
 573
 574         PendingSnippets::iterator pit  = pending_.begin();
 575         PendingSnippets::iterator pend = pending_.end();
 576
 577         pending_.erase(std::remove(pit, pend, latex_snippet), pend);
 578
 579         InProgressProcesses::iterator ipit  = in_progress_.begin();
 580         InProgressProcesses::iterator ipend = in_progress_.end();
 581
 582         for_each(ipit, ipend, EraseSnippet(latex_snippet));
 583
 584         while (ipit != ipend) {
 585                 InProgressProcesses::iterator curr = ipit++;
 586                 if (curr->second.snippets.empty())
 587                         in_progress_.erase(curr);
 588         }
 589 }
 590
 591
 592 void PreviewLoader::Impl::startLoading(bool wait)
 593 {
 594         if (pending_.empty() || !pconverter_)
 595                 return;
 596
 597         // Only start the process off after the buffer is loaded from file.
 598         if (!buffer_.isFullyLoaded())
 599                 return;
 600
 601         LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()");
 602
 603         // As used by the LaTeX file and by the resulting image files
 604         FileName const directory(buffer_.temppath());
 605
 606         FileName const latexfile = unique_tex_filename(directory);
 607         string const filename_base = removeExtension(latexfile.absFileName());
 608
 609         // Create an InProgress instance to place in the map of all
 610         // such processes if it starts correctly.
 611         InProgress inprogress(filename_base, pending_, pconverter_->to());
 612
 613         // clear pending_, so we're ready to start afresh.
 614         pending_.clear();
 615
 616         // Output the LaTeX file.
 617         // we use the encoding of the buffer
 618         Encoding const & enc = buffer_.params().encoding();
 619         ofdocstream of;
 620         try { of.reset(enc.iconvName()); }
 621         catch (iconv_codecvt_facet_exception const & e) {
 622                 LYXERR0("Caught iconv exception: " << e.what()
 623                         << "\nUnable to create LaTeX file: " << latexfile);
 624                 return;
 625         }
 626
 627         TexRow texrow;
 628         otexstream os(of, texrow);
 629         OutputParams runparams(&enc);
 630         LaTeXFeatures features(buffer_, buffer_.params(), runparams);
 631
 632         if (!openFileWrite(of, latexfile))
 633                 return;
 634
 635         if (!of) {
 636                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 637                                         << "Unable to create LaTeX file\n" << latexfile);
 638                 return;
 639         }
 640         of << "\\batchmode\n";
 641
 642         LYXERR(Debug::LATEX, "Format = " << buffer_.params().getDefaultOutputFormat());
 643         string latexparam = "";
 644         bool docformat = !buffer_.params().default_output_format.empty()
 645                         && buffer_.params().default_output_format != "default";
 646         // Use LATEX flavor if the document does not specify a specific
 647         // output format (see bug 9371).
 648         OutputParams::FLAVOR flavor = docformat
 649                                         ? buffer_.params().getOutputFlavor()
 650                                         : OutputParams::LATEX;
 651         if (buffer_.params().encoding().package() == Encoding::japanese) {
 652                 latexparam = " --latex=platex";
 653                 flavor = OutputParams::LATEX;
 654         }
 655         else if (buffer_.params().useNonTeXFonts) {
 656                 if (flavor == OutputParams::LUATEX)
 657                         latexparam = " --latex=lualatex";
 658                 else {
 659                         flavor = OutputParams::XETEX;
 660                         latexparam = " --latex=xelatex";
 661                 }
 662         }
 663         else {
 664                 switch (flavor) {
 665                         case OutputParams::PDFLATEX:
 666                                 latexparam = " --latex=pdflatex";
 667                                 break;
 668                         case OutputParams::XETEX:
 669                                 latexparam = " --latex=xelatex";
 670                                 break;
 671                         case OutputParams::LUATEX:
 672                                 latexparam = " --latex=lualatex";
 673                                 break;
 674                         case OutputParams::DVILUATEX:
 675                                 latexparam = " --latex=dvilualatex";
 676                                 break;
 677                         default:
 678                                 flavor = OutputParams::LATEX;
 679                 }
 680         }
 681         dumpPreamble(os, flavor);
 682         // handle inputenc etc.
 683         // I think, this is already hadled by dumpPreamble(): Kornel
 684         // buffer_.params().writeEncodingPreamble(os, features);
 685         of << "\n\\begin{document}\n";
 686         dumpData(of, inprogress.snippets);
 687         of << "\n\\end{document}\n";
 688         of.close();
 689         if (of.fail()) {
 690                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 691                                          << "File was not closed properly.");
 692                 return;
 693         }
 694
 695         // The conversion command.
 696         ostringstream cs;
 697         cs << pconverter_->command()
 698            << " " << quoteName(latexfile.toFilesystemEncoding())
 699            << " --dpi " << font_scaling_factor_;
 700
 701         // FIXME XHTML
 702         // The colors should be customizable.
 703         if (!buffer_.isExporting()) {
 704                 ColorCode const fg = PreviewLoader::foregroundColor();
 705                 ColorCode const bg = PreviewLoader::backgroundColor();
 706                 cs << " --fg " << theApp()->hexName(fg)
 707                    << " --bg " << theApp()->hexName(bg);
 708         }
 709
 710         cs << latexparam;
 711         if (buffer_.params().bibtex_command != "default")
 712                 cs << " --bibtex=" << quoteName(buffer_.params().bibtex_command);
 713         else if (buffer_.params().encoding().package() == Encoding::japanese)
 714                 cs << " --bibtex=" << quoteName(lyxrc.jbibtex_command);
 715         else
 716                 cs << " --bibtex=" << quoteName(lyxrc.bibtex_command);
 717         if (buffer_.params().bufferFormat() == "lilypond-book")
 718                 cs << " --lilypond";
 719
 720         string const command = cs.str();
 721
 722         if (wait) {
 723                 ForkedCall call(buffer_.filePath(), buffer_.layoutPos());
 724                 int ret = call.startScript(ForkedProcess::Wait, command);
 725                 // FIXME THREAD
 726                 static int fake = (2^20) + 1;
 727                 int pid = fake++;
 728                 inprogress.pid = pid;
 729                 inprogress.command = command;
 730                 in_progress_[pid] = inprogress;
 731                 finishedGenerating(pid, ret);
 732                 return;
 733         }
 734
 735         // Initiate the conversion from LaTeX to bitmap images files.
 736         ForkedCall::SignalTypePtr
 737                 convert_ptr(new ForkedCall::SignalType);
 738         convert_ptr->connect(bind(&Impl::finishedGenerating, this, _1, _2));
 739
 740         ForkedCall call(buffer_.filePath());
 741         int ret = call.startScript(command, convert_ptr);
 742
 743         if (ret != 0) {
 744                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 745                                         << "Unable to start process\n" << command);
 746                 return;
 747         }
 748
 749         // Store the generation process in a list of all such processes
 750         inprogress.pid = call.pid();
 751         inprogress.command = command;
 752         in_progress_[inprogress.pid] = inprogress;
 753 }
 754
 755
 756 double PreviewLoader::displayPixelRatio() const
 757 {
 758         return buffer().params().display_pixel_ratio;
 759 }
 760
 761 void PreviewLoader::Impl::finishedGenerating(pid_t pid, int retval)
 762 {
 763         // Paranoia check!
 764         InProgressProcesses::iterator git = in_progress_.find(pid);
 765         if (git == in_progress_.end()) {
 766                 lyxerr << "PreviewLoader::finishedGenerating(): unable to find "
 767                         "data for PID " << pid << endl;
 768                 finished_generating_ = true;
 769                 return;
 770         }
 771
 772         string const command = git->second.command;
 773         string const status = retval > 0 ? "failed" : "succeeded";
 774         LYXERR(Debug::GRAPHICS, "PreviewLoader::finishedInProgress("
 775                                 << retval << "): processing " << status
 776                                 << " for " << command);
 777         if (retval > 0) {
 778                 in_progress_.erase(git);
 779                 finished_generating_ = true;
 780                 return;
 781         }
 782
 783         // Read the metrics file, if it exists
 784         vector<double> ascent_fractions(git->second.snippets.size());
 785         setAscentFractions(ascent_fractions, git->second.metrics_file);
 786
 787         // Add these newly generated bitmap files to the cache and
 788         // start loading them into LyX.
 789         BitmapFile::const_iterator it  = git->second.snippets.begin();
 790         BitmapFile::const_iterator end = git->second.snippets.end();
 791
 792         list<PreviewImagePtr> newimages;
 793
 794         int metrics_counter = 0;
 795         for (; it != end; ++it, ++metrics_counter) {
 796                 string const & snip = it->first;
 797                 FileName const & file = it->second;
 798                 double af = ascent_fractions[metrics_counter];
 799
 800                 // Add the image to the cache only if it's actually present
 801                 // and not empty (an empty image is signaled by af < 0)
 802                 if (af >= 0 && file.isReadableFile()) {
 803                         PreviewImagePtr ptr(new PreviewImage(parent_, snip, file, af));
 804                         cache_[snip] = ptr;
 805
 806                         newimages.push_back(ptr);
 807                 }
 808
 809         }
 810
 811         // Remove the item from the list of still-executing processes.
 812         in_progress_.erase(git);
 813
 814         // Tell the outside world
 815         list<PreviewImagePtr>::const_reverse_iterator
 816                 nit  = newimages.rbegin();
 817         list<PreviewImagePtr>::const_reverse_iterator
 818                 nend = newimages.rend();
 819         for (; nit != nend; ++nit) {
 820                 imageReady(*nit->get());
 821         }
 822         finished_generating_ = true;
 823 }
 824
 825
 826 void PreviewLoader::Impl::dumpPreamble(otexstream & os, OutputParams::FLAVOR flavor) const
 827 {
 828         // Dump the preamble only.
 829         LYXERR(Debug::LATEX, "dumpPreamble, flavor == " << flavor);
 830         OutputParams runparams(&buffer_.params().encoding());
 831         runparams.flavor = flavor;
 832         runparams.nice = true;
 833         runparams.moving_arg = true;
 834         runparams.free_spacing = true;
 835         runparams.is_child = buffer_.parent();
 836         buffer_.writeLaTeXSource(os, buffer_.filePath(), runparams, Buffer::OnlyPreamble);
 837
 838         // FIXME! This is a HACK! The proper fix is to control the 'true'
 839         // passed to WriteStream below:
 840         // int InsetMathNest::latex(Buffer const &, odocstream & os,
 841         //                          OutputParams const & runparams) const
 842         // {
 843         //      WriteStream wi(os, runparams.moving_arg, true);
 844         //      par_->write(wi);
 845         //      return wi.line();
 846         // }
 847         os << "\n"
 848            << "\\def\\lyxlock{}\n"
 849            << "\n";
 850
 851         // All equation labels appear as "(#)" + preview.sty's rendering of
 852         // the label name
 853         if (lyxrc.preview_hashed_labels)
 854                 os << "\\renewcommand{\\theequation}{\\#}\n";
 855
 856         // Use the preview style file to ensure that each snippet appears on a
 857         // fresh page.
 858         // Also support PDF output (automatically generated e.g. when
 859         // \usepackage[pdftex]{hyperref} is used and XeTeX.
 860         os << "\n"
 861            << "\\usepackage[active,delayed,showlabels,lyx]{preview}\n"
 862            << "\n";
 863 }
 864
 865
 866 void PreviewLoader::Impl::dumpData(odocstream & os,
 867                                    BitmapFile const & vec) const
 868 {
 869         if (vec.empty())
 870                 return;
 871
 872         BitmapFile::const_iterator it  = vec.begin();
 873         BitmapFile::const_iterator end = vec.end();
 874
 875         for (; it != end; ++it) {
 876                 // FIXME UNICODE
 877                 os << "\\begin{preview}\n"
 878                    << from_utf8(it->first)
 879                    << "\n\\end{preview}\n\n";
 880         }
 881 }
 882
 883 } // namespace graphics
 884 } // namespace lyx
 885
 886 #include "moc_PreviewLoader.cpp"