pdf.js/worker_client.js
2011-06-23 23:55:14 +02:00

273 lines
7.4 KiB
JavaScript

/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- /
/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
"use strict";
if (typeof console.time == "undefined") {
var consoleTimer = {};
console.time = function(name) {
consoleTimer[name] = Date.now();
};
console.timeEnd = function(name) {
var time = consoleTimer[name];
if (time == null) {
throw "Unkown timer name " + name;
}
this.log("Timer:", name, Date.now() - time);
};
}
function WorkerPDFDoc(canvas) {
var timer = null
this.ctx = canvas.getContext("2d");
this.canvas = canvas;
this.worker = new Worker('pdf_worker.js');
this.numPage = 1;
this.numPages = null;
var imagesList = {};
var canvasList = {
0: canvas
};
var patternList = {};
var gradient;
var currentX = 0;
var currentXStack = [];
var ctxSpecial = {
"$setCurrentX": function(value) {
currentX = value;
},
"$addCurrentX": function(value) {
currentX += value;
},
"$saveCurrentX": function() {
currentXStack.push(currentX);
},
"$restoreCurrentX": function() {
currentX = currentXStack.pop();
},
"$showText": function(y, text) {
this.translate(currentX, -1 * y);
this.fillText(text, 0, 0);
currentX += this.measureText(text).width;
},
"$putImageData": function(imageData, x, y) {
var imgData = this.getImageData(0, 0, imageData.width, imageData.height);
// Store the .data property to avaid property lookups.
var imageRealData = imageData.data;
var imgRealData = imgData.data;
// Copy over the imageData.
var len = imageRealData.length;
while (len--)
imgRealData[len] = imageRealData[len]
this.putImageData(imgData, x, y);
},
"$drawImage": function(id, x, y, sx, sy, swidth, sheight) {
var image = imagesList[id];
if (!image) {
throw "Image not found: " + id;
}
this.drawImage(image, x, y, image.width, image.height,
sx, sy, swidth, sheight);
},
"$drawCanvas": function(id, x, y, sx, sy, swidth, sheight) {
var canvas = canvasList[id];
if (!canvas) {
throw "Canvas not found";
}
if (sheight != null) {
this.drawImage(canvas, x, y, canvas.width, canvas.height,
sx, sy, swidth, sheight);
} else {
this.drawImage(canvas, x, y, canvas.width, canvas.height);
}
},
"$createLinearGradient": function(x0, y0, x1, y1) {
gradient = this.createLinearGradient(x0, y0, x1, y1);
},
"$createPatternFromCanvas": function(patternId, canvasId, kind) {
var canvas = canvasList[canvasId];
if (!canvas) {
throw "Canvas not found";
}
patternList[patternId] = this.createPattern(canvas, kind);
},
"$addColorStop": function(i, rgba) {
gradient.addColorStop(i, rgba);
},
"$fillStyleGradient": function() {
this.fillStyle = gradient;
},
"$fillStylePattern": function(id) {
var pattern = patternList[id];
if (!pattern) {
throw "Pattern not found";
}
this.fillStyle = pattern;
},
"$strokeStyleGradient": function() {
this.strokeStyle = gradient;
},
"$strokeStylePattern": function(id) {
var pattern = patternList[id];
if (!pattern) {
throw "Pattern not found";
}
this.strokeStyle = pattern;
}
}
function renderProxyCanvas(canvas, cmdQueue) {
var ctx = canvas.getContext("2d");
var cmdQueueLength = cmdQueue.length;
for (var i = 0; i < cmdQueueLength; i++) {
var opp = cmdQueue[i];
if (opp[0] == "$") {
ctx[opp[1]] = opp[2];
} else if (opp[0] in ctxSpecial) {
ctxSpecial[opp[0]].apply(ctx, opp[1]);
} else {
ctx[opp[0]].apply(ctx, opp[1]);
}
}
}
/**
* Functions to handle data sent by the WebWorker.
*/
var actionHandler = {
"log": function(data) {
console.log.apply(console, data);
},
"pdf_num_pages": function(data) {
this.numPages = parseInt(data);
if (this.loadCallback) {
this.loadCallback();
}
},
"font": function(data) {
var base64 = window.btoa(data.raw);
// Add the @font-face rule to the document
var url = "url(data:" + data.mimetype + ";base64," + base64 + ");";
var rule = "@font-face { font-family:'" + data.fontName + "';src:" + url + "}";
var styleSheet = document.styleSheets[0];
styleSheet.insertRule(rule, styleSheet.length);
// Just adding the font-face to the DOM doesn't make it load. It
// seems it's loaded once Gecko notices it's used. Therefore,
// add a div on the page using the loaded font.
var div = document.createElement("div");
var style = 'font-family:"' + data.fontName +
'";position: absolute;top:-99999;left:-99999;z-index:-99999';
div.setAttribute("style", style);
document.body.appendChild(div);
},
"jpeg_stream": function(data) {
var img = new Image();
img.src = "data:image/jpeg;base64," + window.btoa(data.raw);
imagesList[data.id] = img;
},
"canvas_proxy_cmd_queue": function(data) {
var id = data.id;
var cmdQueue = data.cmdQueue;
// Check if there is already a canvas with the given id. If not,
// create a new canvas.
if (!canvasList[id]) {
var newCanvas = document.createElement("canvas");
newCanvas.width = data.width;
newCanvas.height = data.height;
canvasList[id] = newCanvas;
}
// There might be fonts that need to get loaded. Shedule the
// rendering at the end of the event queue ensures this.
setTimeout(function() {
if (id == 0) {
console.time("canvas rendering");
var ctx = this.ctx;
ctx.save();
ctx.fillStyle = "rgb(255, 255, 255)";
ctx.fillRect(0, 0, canvas.width, canvas.height);
ctx.restore();
}
renderProxyCanvas(canvasList[id], cmdQueue);
if (id == 0) console.timeEnd("canvas rendering")
}, 0, this);
}
}
// List to the WebWorker for data and call actionHandler on it.
this.worker.onmessage = function(event) {
var data = event.data;
if (data.action in actionHandler) {
actionHandler[data.action].call(this, data.data);
} else {
throw "Unkown action from worker: " + data.action;
}
}
}
WorkerPDFDoc.prototype.open = function(url, callback) {
var req = new XMLHttpRequest();
req.open("GET", url);
req.mozResponseType = req.responseType = "arraybuffer";
req.expected = (document.URL.indexOf("file:") == 0) ? 0 : 200;
req.onreadystatechange = function() {
if (req.readyState == 4 && req.status == req.expected) {
var data = req.mozResponseArrayBuffer || req.mozResponse ||
req.responseArrayBuffer || req.response;
this.loadCallback = callback;
this.worker.postMessage(data);
this.showPage(this.numPage);
}
}.bind(this);
req.send(null);
}
WorkerPDFDoc.prototype.showPage = function(numPage) {
this.numPage = parseInt(numPage);
this.worker.postMessage(numPage);
if (this.onChangePage) {
this.onChangePage(numPage);
}
}
WorkerPDFDoc.prototype.nextPage = function() {
if (this.numPage == this.numPages) return;
this.showPage(++this.numPage);
}
WorkerPDFDoc.prototype.prevPage = function() {
if (this.numPage == 1) return;
this.showPage(--this.numPage);
}