pdf.js/worker/processor_handler.js

/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- /
/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */

'use strict';

var WorkerProcessorHandler = {
  setup: function(handler) {
    var pdfDoc = null;
    
    handler.on("doc", function(data) {
      // Create only the model of the PDFDoc, which is enough for
      // processing the content of the pdf.
      pdfDoc = new PDFDocModel(new Stream(data));
    });
  
    handler.on("page_request", function(pageNum) {
      pageNum = parseInt(pageNum);

      var page = pdfDoc.getPage(pageNum);

      // The following code does quite the same as Page.prototype.startRendering,
      // but stops at one point and sends the result back to the main thread.
      var gfx = new CanvasGraphics(null);

      var start = Date.now();

      var dependency = [];

      // Pre compile the pdf page and fetch the fonts/images.
      var IRQueue = page.getIRQueue(handler, dependency);

      console.log("page=%d - getIRQueue: time=%dms, len=%d", pageNum, Date.now() - start, IRQueue.fnArray.length);

      if (false /* show used commands */) {
        var cmdMap = {};
  
        var fnArray = IRQueue .fnArray;
        for (var i = 0; i < fnArray.length; i++) {
          var entry = fnArray[i];
          if (entry == "paintReadyFormXObject") {
            //console.log(preCompilation.argsArray[i]);
          }
          if (cmdMap[entry] == null) {
            cmdMap[entry] = 1;
          } else {
            cmdMap[entry] += 1;
          }
        }
        console.log("cmds", JSON.stringify(cmdMap));
      }

      // Filter the dependecies for fonts.
      var fonts = {};
      for (var i = 0; i < dependency.length; i++) {
        var dep = dependency[i];
        if (dep.indexOf('font_') == 0) {
          fonts[dep] = true;
        }
      }


      handler.send("page", {
        pageNum:  pageNum,
        IRQueue:  IRQueue,
        depFonts: Object.keys(fonts)
      });
    }, this);
    
    handler.on("font", function(data) {  
      var objId      = data[0];
      var name       = data[1];
      var file       = data[2];
      var properties = data[3];

      var font = {
        name: name,
        file: file,
        properties: properties
      };

      // Some fonts don't have a file, e.g. the build in ones like Arial.
      if (file) {
        var fontFileDict = new Dict();
        fontFileDict.map = file.dict.map;

        var fontFile = new Stream(file.bytes, file.start,
                                  file.end - file.start, fontFileDict);
                         
        // Check if this is a FlateStream. Otherwise just use the created 
        // Stream one. This makes complex_ttf_font.pdf work.
        var cmf = file.bytes[0];
        if ((cmf & 0x0f) == 0x08) {
          font.file = new FlateStream(fontFile);
        } else {
          font.file = fontFile;
        }          
      }

      var obj = new Font(font.name, font.file, font.properties);

      var str = '';
      var data = obj.data;
      if (data) {
        var length = data.length;
        for (var j = 0; j < length; j++)
          str += String.fromCharCode(data[j]);
      }

      obj.str = str;

      // Remove the data array form the font object, as it's not needed
      // anymore as we sent over the ready str.
      delete obj.data;

      handler.send("font_ready", [objId, obj]);
    });
  }
}