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 #include "texstream.h"
  29
  30 #include "frontends/Application.h" // hexName
  31
  32 #include "insets/Inset.h"
  33
  34 #include "support/convert.h"
  35 #include "support/debug.h"
  36 #include "support/FileName.h"
  37 #include "support/filetools.h"
  38 #include "support/ForkedCalls.h"
  39 #include "support/lstrings.h"
  40
  41 #include "support/TempFile.h"
  42
  43 #include <atomic>
  44 #include <fstream>
  45 #include <iomanip>
  46 #include <memory>
  47 #include <mutex>
  48 #include <sstream>
  49
  50 #include <QTimer>
  51
  52 using namespace std;
  53 using namespace lyx::support;
  54
  55
  56
  57 namespace {
  58
  59 typedef pair<string, FileName> SnippetPair;
  60
  61 // A list of all snippets to be converted to previews
  62 typedef list<string> PendingSnippets;
  63
  64 // Each item in the vector is a pair<snippet, image file name>.
  65 typedef vector<SnippetPair> BitmapFile;
  66
  67
  68 FileName const unique_tex_filename(FileName const & bufferpath)
  69 {
  70         TempFile tempfile(bufferpath, "lyxpreviewXXXXXX.tex");
  71         tempfile.setAutoRemove(false);
  72         return tempfile.name();
  73 }
  74
  75
  76 void setAscentFractions(vector<double> & ascent_fractions,
  77                         FileName const & metrics_file)
  78 {
  79         // If all else fails, then the images will have equal ascents and
  80         // descents.
  81         vector<double>::iterator it  = ascent_fractions.begin();
  82         vector<double>::iterator end = ascent_fractions.end();
  83         fill(it, end, 0.5);
  84
  85         ifstream in(metrics_file.toFilesystemEncoding().c_str());
  86         if (!in.good()) {
  87                 LYXERR(lyx::Debug::GRAPHICS, "setAscentFractions(" << metrics_file << ")\n"
  88                         << "Unable to open file!");
  89                 return;
  90         }
  91
  92         bool error = false;
  93
  94         int snippet_counter = 1;
  95         while (!in.eof() && it != end) {
  96                 string snippet;
  97                 int id;
  98                 double ascent_fraction;
  99
 100                 in >> snippet >> id >> ascent_fraction;
 101
 102                 if (!in.good())
 103                         // eof after all
 104                         break;
 105
 106                 error = snippet != "Snippet";
 107                 if (error)
 108                         break;
 109
 110                 error = id != snippet_counter;
 111                 if (error)
 112                         break;
 113
 114                 *it = ascent_fraction;
 115
 116                 ++snippet_counter;
 117                 ++it;
 118         }
 119
 120         if (error) {
 121                 LYXERR(lyx::Debug::GRAPHICS, "setAscentFractions(" << metrics_file << ")\n"
 122                         << "Error reading file!\n");
 123         }
 124 }
 125
 126
 127 class FindFirst
 128 {
 129 public:
 130         FindFirst(string const & comp) : comp_(comp) {}
 131         bool operator()(SnippetPair const & sp) const { return sp.first == comp_; }
 132 private:
 133         string const comp_;
 134 };
 135
 136
 137 /// Store info on a currently executing, forked process.
 138 class InProgress {
 139 public:
 140         ///
 141         InProgress() : pid(0) {}
 142         ///
 143         InProgress(string const & filename_base,
 144                    PendingSnippets const & pending,
 145                    string const & to_format);
 146         /// Remove any files left lying around and kill the forked process.
 147         void stop() const;
 148
 149         ///
 150         pid_t pid;
 151         ///
 152         string command;
 153         ///
 154         FileName metrics_file;
 155         ///
 156         BitmapFile snippets;
 157 };
 158
 159 typedef map<pid_t, InProgress>  InProgressProcesses;
 160
 161 typedef InProgressProcesses::value_type InProgressProcess;
 162
 163 } // namespace anon
 164
 165
 166
 167 namespace lyx {
 168 namespace graphics {
 169
 170 class PreviewLoader::Impl {
 171 public:
 172         ///
 173         Impl(PreviewLoader & p, Buffer const & b);
 174         /// Stop any InProgress items still executing.
 175         ~Impl();
 176         ///
 177         PreviewImage const * preview(string const & latex_snippet) const;
 178         ///
 179         PreviewLoader::Status status(string const & latex_snippet) const;
 180         ///
 181         void add(string const & latex_snippet);
 182         ///
 183         void remove(string const & latex_snippet);
 184         /// \p wait whether to wait for the process to complete or, instead,
 185         /// to do it in the background.
 186         void startLoading(bool wait = false);
 187         ///
 188         void refreshPreviews();
 189
 190         /// Emit this signal when an image is ready for display.
 191         signals2::signal<void(PreviewImage const &)> imageReady;
 192
 193         Buffer const & buffer() const { return buffer_; }
 194
 195         lyx::Converter const * setConverter(string const & from);
 196
 197 private:
 198         /// Called by the ForkedCall process that generated the bitmap files.
 199         void finishedGenerating(pid_t, int);
 200         ///
 201         void dumpPreamble(otexstream &, OutputParams::FLAVOR) const;
 202         ///
 203         void dumpData(odocstream &, BitmapFile const &) const;
 204
 205         /** cache_ allows easy retrieval of already-generated images
 206          *  using the LaTeX snippet as the identifier.
 207          */
 208         typedef std::shared_ptr<PreviewImage> PreviewImagePtr;
 209         ///
 210         typedef map<string, PreviewImagePtr> Cache;
 211         ///
 212         Cache cache_;
 213
 214         /** pending_ stores the LaTeX snippets in anticipation of them being
 215          *  sent to the converter.
 216          */
 217         PendingSnippets pending_;
 218
 219         /** in_progress_ stores all forked processes so that we can proceed
 220          *  thereafter.
 221             The map uses the conversion commands as its identifiers.
 222          */
 223         InProgressProcesses in_progress_;
 224
 225         ///
 226         PreviewLoader & parent_;
 227         ///
 228         Buffer const & buffer_;
 229         ///
 230         mutable int font_scaling_factor_;
 231         ///
 232         mutable int fg_color_;
 233         ///
 234         mutable int bg_color_;
 235         ///
 236         QTimer * delay_refresh_;
 237         ///
 238         bool finished_generating_;
 239
 240         /// We don't own this
 241         static lyx::Converter const * pconverter_;
 242
 243         signals2::scoped_connection connection_;
 244 };
 245
 246
 247 lyx::Converter const * PreviewLoader::Impl::pconverter_;
 248
 249
 250 //
 251 // The public interface, defined in PreviewLoader.h
 252 //
 253
 254 PreviewLoader::PreviewLoader(Buffer const & b)
 255         : pimpl_(new Impl(*this, b))
 256 {}
 257
 258
 259 PreviewLoader::~PreviewLoader()
 260 {
 261         delete pimpl_;
 262 }
 263
 264
 265 PreviewImage const * PreviewLoader::preview(string const & latex_snippet) const
 266 {
 267         return pimpl_->preview(latex_snippet);
 268 }
 269
 270
 271 PreviewLoader::Status PreviewLoader::status(string const & latex_snippet) const
 272 {
 273         return pimpl_->status(latex_snippet);
 274 }
 275
 276
 277 void PreviewLoader::add(string const & latex_snippet) const
 278 {
 279         pimpl_->add(latex_snippet);
 280 }
 281
 282
 283 void PreviewLoader::remove(string const & latex_snippet) const
 284 {
 285         pimpl_->remove(latex_snippet);
 286 }
 287
 288
 289 void PreviewLoader::startLoading(bool wait) const
 290 {
 291         pimpl_->startLoading(wait);
 292 }
 293
 294
 295 void PreviewLoader::refreshPreviews()
 296 {
 297         pimpl_->refreshPreviews();
 298 }
 299
 300
 301 signals2::connection PreviewLoader::connect(slot const & slot) const
 302 {
 303         return pimpl_->imageReady.connect(slot);
 304 }
 305
 306
 307 void PreviewLoader::emitSignal(PreviewImage const & pimage) const
 308 {
 309         pimpl_->imageReady(pimage);
 310 }
 311
 312
 313 Buffer const & PreviewLoader::buffer() const
 314 {
 315         return pimpl_->buffer();
 316 }
 317
 318 } // namespace graphics
 319 } // namespace lyx
 320
 321
 322 // The details of the Impl
 323 // =======================
 324
 325 namespace {
 326
 327 class IncrementedFileName {
 328 public:
 329         IncrementedFileName(string const & to_format,
 330                             string const & filename_base)
 331                 : to_format_(to_format), base_(filename_base), counter_(1)
 332         {}
 333
 334         SnippetPair const operator()(string const & snippet)
 335         {
 336                 ostringstream os;
 337                 os << base_ << counter_++ << '.' << to_format_;
 338                 string const file = os.str();
 339
 340                 return make_pair(snippet, FileName(file));
 341         }
 342
 343 private:
 344         string const & to_format_;
 345         string const & base_;
 346         int counter_;
 347 };
 348
 349
 350 InProgress::InProgress(string const & filename_base,
 351                        PendingSnippets const & pending,
 352                        string const & to_format)
 353         : pid(0),
 354           metrics_file(filename_base + ".metrics"),
 355           snippets(pending.size())
 356 {
 357         PendingSnippets::const_iterator pit  = pending.begin();
 358         PendingSnippets::const_iterator pend = pending.end();
 359         BitmapFile::iterator sit = snippets.begin();
 360
 361         transform(pit, pend, sit,
 362                        IncrementedFileName(to_format, filename_base));
 363 }
 364
 365
 366 void InProgress::stop() const
 367 {
 368         if (pid)
 369                 ForkedCallsController::kill(pid, 0);
 370
 371         if (!metrics_file.empty())
 372                 metrics_file.removeFile();
 373
 374         BitmapFile::const_iterator vit  = snippets.begin();
 375         BitmapFile::const_iterator vend = snippets.end();
 376         for (; vit != vend; ++vit) {
 377                 if (!vit->second.empty())
 378                         vit->second.removeFile();
 379         }
 380 }
 381
 382 } // namespace anon
 383
 384
 385 namespace lyx {
 386 namespace graphics {
 387
 388 PreviewLoader::Impl::Impl(PreviewLoader & p, Buffer const & b)
 389         : parent_(p), buffer_(b), finished_generating_(true)
 390 {
 391         font_scaling_factor_ = int(buffer_.fontScalingFactor());
 392         if (theApp()) {
 393                 fg_color_ = strtol(theApp()->hexName(foregroundColor()).c_str(), 0, 16);
 394                 bg_color_ = strtol(theApp()->hexName(backgroundColor()).c_str(), 0, 16);
 395         } else {
 396                 fg_color_ = 0x0;
 397                 bg_color_ = 0xffffff;
 398         }
 399         if (!pconverter_)
 400                 pconverter_ = setConverter("lyxpreview");
 401
 402         delay_refresh_ = new QTimer(&parent_);
 403         delay_refresh_->setSingleShot(true);
 404         QObject::connect(delay_refresh_, SIGNAL(timeout()),
 405                          &parent_, SLOT(refreshPreviews()));
 406 }
 407
 408
 409 lyx::Converter const * PreviewLoader::Impl::setConverter(string const & from)
 410 {
 411         typedef vector<string> FmtList;
 412         FmtList const & loadableFormats = graphics::Cache::get().loadableFormats();
 413         FmtList::const_iterator it = loadableFormats.begin();
 414         FmtList::const_iterator const end = loadableFormats.end();
 415
 416         for (; it != end; ++it) {
 417                 string const to = *it;
 418                 if (from == to)
 419                         continue;
 420
 421                 lyx::Converter const * ptr = lyx::theConverters().getConverter(from, to);
 422                 if (ptr)
 423                         return ptr;
 424         }
 425
 426         // Show the error only once. This is thread-safe.
 427         static nullptr_t no_conv = [&]{
 428                 LYXERR0("PreviewLoader::startLoading()\n"
 429                         << "No converter from \"" << from
 430                         << "\" format has been defined.");
 431                 return nullptr;
 432         } ();
 433
 434         return no_conv;
 435 }
 436
 437
 438 PreviewLoader::Impl::~Impl()
 439 {
 440         delete delay_refresh_;
 441
 442         InProgressProcesses::iterator ipit  = in_progress_.begin();
 443         InProgressProcesses::iterator ipend = in_progress_.end();
 444
 445         for (; ipit != ipend; ++ipit)
 446                 ipit->second.stop();
 447 }
 448
 449
 450 PreviewImage const *
 451 PreviewLoader::Impl::preview(string const & latex_snippet) const
 452 {
 453         int fs = int(buffer_.fontScalingFactor());
 454         int fg = 0x0;
 455         int bg = 0xffffff;
 456         if (theApp()) {
 457                 fg = strtol(theApp()->hexName(foregroundColor()).c_str(), 0, 16);
 458                 bg = strtol(theApp()->hexName(backgroundColor()).c_str(), 0, 16);
 459         }
 460         if (font_scaling_factor_ != fs || fg_color_ != fg || bg_color_ != bg) {
 461                 // Schedule refresh of all previews on zoom or color changes.
 462                 // The previews are regenerated only after the zoom factor
 463                 // has not been changed for about 1 second.
 464                 fg_color_ = fg;
 465                 bg_color_ = bg;
 466                 delay_refresh_->start(1000);
 467         }
 468         // Don't try to access the cache until we are done.
 469         if (delay_refresh_->isActive() || !finished_generating_)
 470                 return 0;
 471         Cache::const_iterator it = cache_.find(latex_snippet);
 472         return (it == cache_.end()) ? 0 : it->second.get();
 473 }
 474
 475
 476 void PreviewLoader::Impl::refreshPreviews()
 477 {
 478         font_scaling_factor_ = int(buffer_.fontScalingFactor());
 479         // Reschedule refresh until the previous process completed.
 480         if (!finished_generating_) {
 481                 delay_refresh_->start(1000);
 482                 return;
 483         }
 484         Cache::const_iterator cit = cache_.begin();
 485         Cache::const_iterator cend = cache_.end();
 486         while (cit != cend)
 487                 parent_.remove((cit++)->first);
 488         finished_generating_ = false;
 489         buffer_.updatePreviews();
 490 }
 491
 492
 493 namespace {
 494
 495 class FindSnippet {
 496 public:
 497         FindSnippet(string const & s) : snippet_(s) {}
 498         bool operator()(InProgressProcess const & process) const
 499         {
 500                 BitmapFile const & snippets = process.second.snippets;
 501                 BitmapFile::const_iterator beg  = snippets.begin();
 502                 BitmapFile::const_iterator end = snippets.end();
 503                 return find_if(beg, end, FindFirst(snippet_)) != end;
 504         }
 505
 506 private:
 507         string const snippet_;
 508 };
 509
 510 } // namespace anon
 511
 512 PreviewLoader::Status
 513 PreviewLoader::Impl::status(string const & latex_snippet) const
 514 {
 515         Cache::const_iterator cit = cache_.find(latex_snippet);
 516         if (cit != cache_.end())
 517                 return Ready;
 518
 519         PendingSnippets::const_iterator pit  = pending_.begin();
 520         PendingSnippets::const_iterator pend = pending_.end();
 521
 522         pit = find(pit, pend, latex_snippet);
 523         if (pit != pend)
 524                 return InQueue;
 525
 526         InProgressProcesses::const_iterator ipit  = in_progress_.begin();
 527         InProgressProcesses::const_iterator ipend = in_progress_.end();
 528
 529         ipit = find_if(ipit, ipend, FindSnippet(latex_snippet));
 530         if (ipit != ipend)
 531                 return Processing;
 532
 533         return NotFound;
 534 }
 535
 536
 537 void PreviewLoader::Impl::add(string const & latex_snippet)
 538 {
 539         if (!pconverter_ || status(latex_snippet) != NotFound)
 540                 return;
 541
 542         string const snippet = trim(latex_snippet);
 543         if (snippet.empty())
 544                 return;
 545
 546         LYXERR(Debug::GRAPHICS, "adding snippet:\n" << snippet);
 547
 548         pending_.push_back(snippet);
 549 }
 550
 551
 552 namespace {
 553
 554 class EraseSnippet {
 555 public:
 556         EraseSnippet(string const & s) : snippet_(s) {}
 557         void operator()(InProgressProcess & process)
 558         {
 559                 BitmapFile & snippets = process.second.snippets;
 560                 BitmapFile::iterator it  = snippets.begin();
 561                 BitmapFile::iterator end = snippets.end();
 562
 563                 it = find_if(it, end, FindFirst(snippet_));
 564                 if (it != end)
 565                         snippets.erase(it, it+1);
 566         }
 567
 568 private:
 569         string const & snippet_;
 570 };
 571
 572 } // namespace anon
 573
 574
 575 void PreviewLoader::Impl::remove(string const & latex_snippet)
 576 {
 577         Cache::iterator cit = cache_.find(latex_snippet);
 578         if (cit != cache_.end())
 579                 cache_.erase(cit);
 580
 581         PendingSnippets::iterator pit  = pending_.begin();
 582         PendingSnippets::iterator pend = pending_.end();
 583
 584         pending_.erase(std::remove(pit, pend, latex_snippet), pend);
 585
 586         InProgressProcesses::iterator ipit  = in_progress_.begin();
 587         InProgressProcesses::iterator ipend = in_progress_.end();
 588
 589         for_each(ipit, ipend, EraseSnippet(latex_snippet));
 590
 591         while (ipit != ipend) {
 592                 InProgressProcesses::iterator curr = ipit++;
 593                 if (curr->second.snippets.empty())
 594                         in_progress_.erase(curr);
 595         }
 596 }
 597
 598
 599 void PreviewLoader::Impl::startLoading(bool wait)
 600 {
 601         if (pending_.empty() || !pconverter_)
 602                 return;
 603
 604         // Only start the process off after the buffer is loaded from file.
 605         if (!buffer_.isFullyLoaded())
 606                 return;
 607
 608         LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()");
 609
 610         // As used by the LaTeX file and by the resulting image files
 611         FileName const directory(buffer_.temppath());
 612
 613         FileName const latexfile = unique_tex_filename(directory);
 614         string const filename_base = removeExtension(latexfile.absFileName());
 615
 616         // Create an InProgress instance to place in the map of all
 617         // such processes if it starts correctly.
 618         InProgress inprogress(filename_base, pending_, pconverter_->to());
 619
 620         // clear pending_, so we're ready to start afresh.
 621         pending_.clear();
 622
 623         // Output the LaTeX file.
 624         // we use the encoding of the buffer
 625         Encoding const & enc = buffer_.params().encoding();
 626         ofdocstream of;
 627         try { of.reset(enc.iconvName()); }
 628         catch (iconv_codecvt_facet_exception const & e) {
 629                 LYXERR0("Caught iconv exception: " << e.what()
 630                         << "\nUnable to create LaTeX file: " << latexfile);
 631                 return;
 632         }
 633
 634         otexstream os(of);
 635         OutputParams runparams(&enc);
 636         LaTeXFeatures features(buffer_, buffer_.params(), runparams);
 637
 638         if (!openFileWrite(of, latexfile))
 639                 return;
 640
 641         if (!of) {
 642                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 643                                         << "Unable to create LaTeX file\n" << latexfile);
 644                 return;
 645         }
 646         of << "\\batchmode\n";
 647
 648         // Set \jobname of previews to the document name (see bug 9627)
 649         of << "\\def\\jobname{"
 650            << from_utf8(changeExtension(buffer_.latexName(true), ""))
 651            << "}\n";
 652
 653         LYXERR(Debug::LATEX, "Format = " << buffer_.params().getDefaultOutputFormat());
 654         string latexparam = "";
 655         bool docformat = !buffer_.params().default_output_format.empty()
 656                         && buffer_.params().default_output_format != "default";
 657         // Use LATEX flavor if the document does not specify a specific
 658         // output format (see bug 9371).
 659         OutputParams::FLAVOR flavor = docformat
 660                                         ? buffer_.params().getOutputFlavor()
 661                                         : OutputParams::LATEX;
 662         if (buffer_.params().encoding().package() == Encoding::japanese) {
 663                 latexparam = " --latex=platex";
 664                 flavor = OutputParams::LATEX;
 665         }
 666         else if (buffer_.params().useNonTeXFonts) {
 667                 if (flavor == OutputParams::LUATEX)
 668                         latexparam = " --latex=lualatex";
 669                 else {
 670                         flavor = OutputParams::XETEX;
 671                         latexparam = " --latex=xelatex";
 672                 }
 673         }
 674         else {
 675                 switch (flavor) {
 676                         case OutputParams::PDFLATEX:
 677                                 latexparam = " --latex=pdflatex";
 678                                 break;
 679                         case OutputParams::XETEX:
 680                                 latexparam = " --latex=xelatex";
 681                                 break;
 682                         case OutputParams::LUATEX:
 683                                 latexparam = " --latex=lualatex";
 684                                 break;
 685                         case OutputParams::DVILUATEX:
 686                                 latexparam = " --latex=dvilualatex";
 687                                 break;
 688                         default:
 689                                 flavor = OutputParams::LATEX;
 690                 }
 691         }
 692         dumpPreamble(os, flavor);
 693         // handle inputenc etc.
 694         // I think, this is already hadled by dumpPreamble(): Kornel
 695         // buffer_.params().writeEncodingPreamble(os, features);
 696         of << "\n\\begin{document}\n";
 697         dumpData(of, inprogress.snippets);
 698         of << "\n\\end{document}\n";
 699         of.close();
 700         if (of.fail()) {
 701                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 702                                          << "File was not closed properly.");
 703                 return;
 704         }
 705
 706         // The conversion command.
 707         ostringstream cs;
 708         cs << pconverter_->command()
 709            << " " << quoteName(latexfile.toFilesystemEncoding())
 710            << " --dpi " << font_scaling_factor_;
 711
 712         // FIXME XHTML
 713         // The colors should be customizable.
 714         if (!buffer_.isExporting()) {
 715                 ColorCode const fg = PreviewLoader::foregroundColor();
 716                 ColorCode const bg = PreviewLoader::backgroundColor();
 717                 cs << " --fg " << theApp()->hexName(fg)
 718                    << " --bg " << theApp()->hexName(bg);
 719         }
 720
 721         cs << latexparam;
 722         cs << " --bibtex=" << quoteName(buffer_.params().bibtexCommand());
 723         if (buffer_.params().bufferFormat() == "lilypond-book")
 724                 cs << " --lilypond";
 725
 726         string const command = cs.str();
 727
 728         if (wait) {
 729                 ForkedCall call(buffer_.filePath(), buffer_.layoutPos());
 730                 int ret = call.startScript(ForkedProcess::Wait, command);
 731                 static atomic_int fake((2^20) + 1);
 732                 int pid = fake++;
 733                 inprogress.pid = pid;
 734                 inprogress.command = command;
 735                 in_progress_[pid] = inprogress;
 736                 finishedGenerating(pid, ret);
 737                 return;
 738         }
 739
 740         // Initiate the conversion from LaTeX to bitmap images files.
 741         ForkedCall::sigPtr convert_ptr = make_shared<ForkedCall::sig>();
 742         // This is a scoped connection
 743         connection_ = convert_ptr->connect([this](pid_t pid, int retval){
 744                         finishedGenerating(pid, retval);
 745                 });
 746
 747         ForkedCall call(buffer_.filePath());
 748         int ret = call.startScript(command, convert_ptr);
 749
 750         if (ret != 0) {
 751                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 752                                         << "Unable to start process\n" << command);
 753                 return;
 754         }
 755
 756         // Store the generation process in a list of all such processes
 757         inprogress.pid = call.pid();
 758         inprogress.command = command;
 759         in_progress_[inprogress.pid] = inprogress;
 760 }
 761
 762
 763 double PreviewLoader::displayPixelRatio() const
 764 {
 765         return buffer().params().display_pixel_ratio;
 766 }
 767
 768 void PreviewLoader::Impl::finishedGenerating(pid_t pid, int retval)
 769 {
 770         // Paranoia check!
 771         InProgressProcesses::iterator git = in_progress_.find(pid);
 772         if (git == in_progress_.end()) {
 773                 lyxerr << "PreviewLoader::finishedGenerating(): unable to find "
 774                         "data for PID " << pid << endl;
 775                 finished_generating_ = true;
 776                 return;
 777         }
 778
 779         string const command = git->second.command;
 780         string const status = retval > 0 ? "failed" : "succeeded";
 781         LYXERR(Debug::GRAPHICS, "PreviewLoader::finishedInProgress("
 782                                 << retval << "): processing " << status
 783                                 << " for " << command);
 784         if (retval > 0) {
 785                 in_progress_.erase(git);
 786                 finished_generating_ = true;
 787                 return;
 788         }
 789
 790         // Read the metrics file, if it exists
 791         vector<double> ascent_fractions(git->second.snippets.size());
 792         setAscentFractions(ascent_fractions, git->second.metrics_file);
 793
 794         // Add these newly generated bitmap files to the cache and
 795         // start loading them into LyX.
 796         BitmapFile::const_iterator it  = git->second.snippets.begin();
 797         BitmapFile::const_iterator end = git->second.snippets.end();
 798
 799         list<PreviewImagePtr> newimages;
 800
 801         int metrics_counter = 0;
 802         for (; it != end; ++it, ++metrics_counter) {
 803                 string const & snip = it->first;
 804                 FileName const & file = it->second;
 805                 double af = ascent_fractions[metrics_counter];
 806
 807                 // Add the image to the cache only if it's actually present
 808                 // and not empty (an empty image is signaled by af < 0)
 809                 if (af >= 0 && file.isReadableFile()) {
 810                         PreviewImagePtr ptr(new PreviewImage(parent_, snip, file, af));
 811                         cache_[snip] = ptr;
 812
 813                         newimages.push_back(ptr);
 814                 }
 815
 816         }
 817
 818         // Remove the item from the list of still-executing processes.
 819         in_progress_.erase(git);
 820
 821         // Tell the outside world
 822         list<PreviewImagePtr>::const_reverse_iterator
 823                 nit  = newimages.rbegin();
 824         list<PreviewImagePtr>::const_reverse_iterator
 825                 nend = newimages.rend();
 826         for (; nit != nend; ++nit) {
 827                 imageReady(*nit->get());
 828         }
 829         finished_generating_ = true;
 830 }
 831
 832
 833 void PreviewLoader::Impl::dumpPreamble(otexstream & os, OutputParams::FLAVOR flavor) const
 834 {
 835         // Dump the preamble only.
 836         LYXERR(Debug::LATEX, "dumpPreamble, flavor == " << flavor);
 837         OutputParams runparams(&buffer_.params().encoding());
 838         runparams.flavor = flavor;
 839         runparams.nice = true;
 840         runparams.moving_arg = true;
 841         runparams.free_spacing = true;
 842         runparams.is_child = buffer_.parent();
 843         buffer_.writeLaTeXSource(os, buffer_.filePath(), runparams, Buffer::OnlyPreamble);
 844
 845         // FIXME! This is a HACK! The proper fix is to control the 'true'
 846         // passed to WriteStream below:
 847         // int InsetMathNest::latex(Buffer const &, odocstream & os,
 848         //                          OutputParams const & runparams) const
 849         // {
 850         //      WriteStream wi(os, runparams.moving_arg, true);
 851         //      par_->write(wi);
 852         //      return wi.line();
 853         // }
 854         os << "\n"
 855            << "\\def\\lyxlock{}\n"
 856            << "\n";
 857
 858         // All equation labels appear as "(#)" + preview.sty's rendering of
 859         // the label name
 860         if (lyxrc.preview_hashed_labels)
 861                 os << "\\renewcommand{\\theequation}{\\#}\n";
 862
 863         // Use the preview style file to ensure that each snippet appears on a
 864         // fresh page.
 865         // Also support PDF output (automatically generated e.g. when
 866         // \usepackage[pdftex]{hyperref} is used and XeTeX.
 867         os << "\n"
 868            << "\\usepackage[active,delayed,showlabels,lyx]{preview}\n"
 869            << "\n";
 870 }
 871
 872
 873 void PreviewLoader::Impl::dumpData(odocstream & os,
 874                                    BitmapFile const & vec) const
 875 {
 876         if (vec.empty())
 877                 return;
 878
 879         BitmapFile::const_iterator it  = vec.begin();
 880         BitmapFile::const_iterator end = vec.end();
 881
 882         for (; it != end; ++it) {
 883                 // FIXME UNICODE
 884                 os << "\\begin{preview}\n"
 885                    << from_utf8(it->first)
 886                    << "\n\\end{preview}\n\n";
 887         }
 888 }
 889
 890 } // namespace graphics
 891 } // namespace lyx
 892
 893 #include "moc_PreviewLoader.cpp"