Refactor to execute IR on main thead by posting messages to itself

worker/handler.js

@@ -0,0 +1,84 @@
+/* -*- 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 WorkerHandler = {
+  setup: function(handler) {
+    var pdfDoc = null;
+    
+    handler.on("doc", function(data) {
+      pdfDoc = new PDFDoc(new Stream(data));
+      console.log("setup pdfDoc");
+    });
+  
+    handler.on("page_request", function(pageNum) {
+      pageNum = parseInt(pageNum);
+      console.log("about to process page", 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 fonts = [];
+      // TODO: Figure out how image loading is handled inside the worker.
+      var images = new ImagesLoader();
+
+      // Pre compile the pdf page and fetch the fonts/images.
+      var preCompilation = page.preCompile(gfx, fonts, images);
+
+      // Extract the minimum of font data that is required to build all required
+      // font stuff on the main thread.
+      var fontsMin = [];
+      for (var i = 0; i < fonts.length; i++) {
+        var font = fonts[i];
+
+        fontsMin.push({
+          name:       font.name,
+          file:       font.file,
+          properties: font.properties
+        });
+      }
+
+      // TODO: Handle images here.
+
+      console.log("about to send page", pageNum);
+
+      if (true /* show used commands */) {
+        var cmdMap = {};
+  
+        var fnArray = preCompilation.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;
+          }
+        }
+
+        // // Make a copy of the fnArray and show all cmds it has.
+        // var fnArray = preCompilation.fnArray.slice(0).sort();
+        // for (var i = 0; i < fnArray.length; true) {
+        //   if (fnArray[i] == fnArray[i + 1]) {
+        //     fnArray.splice(i, 1);
+        //   } else {
+        //     i++;
+        //   }
+        // }
+        console.log("cmds", JSON.stringify(cmdMap));
+      } 
+
+      handler.send("page", {
+        pageNum:        pageNum,
+        fonts:          fontsMin,
+        images:         [],
+        preCompilation: preCompilation,
+      });
+    }, this);
+  }
+}