Mercurial > hg > orthanc-stone
view Applications/StoneWebViewer/WebApplication/pdf-viewer.js @ 1794:fe5c7311a7fd
fix for msvc 2008
author | Sebastien Jodogne <s.jodogne@gmail.com> |
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date | Mon, 17 May 2021 18:03:47 +0200 |
parents | 9ac2a65d4172 |
children | 3889ae96d2e9 |
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/** * Stone of Orthanc * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics * Department, University Hospital of Liege, Belgium * Copyright (C) 2017-2021 Osimis S.A., Belgium * * This program is free software: you can redistribute it and/or * modify it under the terms of the GNU Affero General Public License * as published by the Free Software Foundation, either version 3 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. **/ /** * This source file is an adaptation for Vue.js of the sample code * "Previous/Next example" of PDF.js: * https://mozilla.github.io/pdf.js/examples/ * * ======================================================================= * * Original license of the sample code: * * Copyright 2014 Mozilla Foundation * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. **/ // Loaded via <script> tag, create shortcut to access PDF.js exports. var pdfjsLib = window['pdfjs-dist/build/pdf']; // The workerSrc property shall be specified. pdfjsLib.GlobalWorkerOptions.workerSrc = 'https://cdn.jsdelivr.net/npm/pdfjs-dist@2.5.207/build/pdf.worker.min.js'; var ZOOM_FACTOR = 1.3; var FIT_MARGIN = 10; // Additional margin for width/height fitting, in order to avoid spurious scrollbars Vue.component('pdf-viewer', { props: [ 'prefix' ], template: '#pdf-viewer', data: function() { return { container: null, canvas: null, ctx: null, pdf: null, // "pdf" must correspond to a "Uint8Array" scale: 1, countPages: 0, currentPage: 0, pdfDoc: null, isRendering: false, pageNumPending: null } }, mounted: function() { this.container = document.getElementById(this.prefix + '-container'); this.canvas = document.getElementById(this.prefix + '-canvas'); this.ctx = this.canvas.getContext('2d'); if (this.container === null || this.canvas === null || this.ctx === null) { alert('Bad viewer configuration'); } var that = this; this.container.addEventListener('wheel', function(event) { that.MouseWheel(event); }); }, methods: { NextPage: function() { if (this.pdfDoc !== null && this.currentPage < this.pdfDoc.numPages) { this.QueueRenderPage(this.currentPage + 1); } }, PreviousPage: function() { if (this.pdfDoc !== null && this.currentPage > 1) { this.QueueRenderPage(this.currentPage - 1); } }, FitWidth: function() { if (this.pdfDoc !== null) { var that = this; this.pdfDoc.getPage(this.currentPage).then(function(page) { // https://github.com/mozilla/pdf.js/issues/5628 // https://stackoverflow.com/a/21064102/881731 // https://stackoverflow.com/a/60008044/881731 var scrollbarWidth = window.innerWidth - document.body.clientWidth + FIT_MARGIN; that.scale = (that.container.offsetWidth - scrollbarWidth) / page.getViewport({ scale: 1.0 }).width; that.QueueRenderPage(that.currentPage); }); } }, FitHeight: function() { if (this.pdfDoc !== null) { var that = this; this.pdfDoc.getPage(this.currentPage).then(function(page) { // The computation below assumes that "line-height: 0px" CSS // on the parent element of the canvas. // https://github.com/mozilla/pdf.js/issues/5628 var scrollbarHeight = window.innerHeight - document.body.clientHeight + FIT_MARGIN; that.scale = (that.container.offsetHeight - scrollbarHeight) / page.getViewport({ scale: 1.0 }).height; that.QueueRenderPage(that.currentPage); }); } }, ZoomIn: function() { this.scale *= ZOOM_FACTOR; this.QueueRenderPage(this.currentPage); }, ZoomOut: function() { this.scale /= ZOOM_FACTOR; this.QueueRenderPage(this.currentPage); }, LoadPdf: function(pdf) { if (!this.isRendering && pdf.length > 0) { this.pdf = pdf; this.isRendering = true; var that = this; pdfjsLib.getDocument(this.pdf).promise.then(function(pdfDoc_) { that.pdfDoc = pdfDoc_; that.currentPage = 1; that.countPages = pdfDoc_.numPages; that.scale = 1; that.isRendering = false; that.pageNumPending = null; // Initial/first page rendering, after fitting the PDF to the available viewport that.FitHeight(); }); } }, RenderPage: function(pageNum) { var that = this; if (this.pdfDoc !== null && pageNum >= 1 && pageNum <= this.countPages) { this.isRendering = true; this.pdfDoc.getPage(pageNum).then(function(page) { var viewport = page.getViewport({scale: that.scale}); that.canvas.style['background-color'] = 'white'; // avoids flickering while the page changes that.canvas.height = viewport.height; that.canvas.width = viewport.width; // Horizontal centering of the canvas. This requires CSS // "position: relative" on the canvas element. if (that.canvas.width < that.container.clientWidth) { that.canvas.style.left = Math.floor((that.container.clientWidth - viewport.width) / 2) + 'px'; } else { that.canvas.style.left = '0px'; } // Render PDF page into canvas context var renderContext = { canvasContext: that.ctx, viewport: viewport }; var renderTask = page.render(renderContext); // Wait for rendering to finish renderTask.promise.then(function() { that.isRendering = false; that.currentPage = pageNum; if (that.pageNumPending !== null) { // New page rendering is pending that.currentPage = that.pageNumPending; that.pageNumPending = null; that.RenderPage(); } }); }); } }, QueueRenderPage: function(pageNum) { if (this.isRendering) { this.pageNumPending = pageNum; } else { this.RenderPage(pageNum); } }, MouseWheel: function(event) { if (event.ctrlKey) { if (event.deltaY < 0) { this.ZoomIn(); event.preventDefault(); } else if (event.deltaY > 0) { this.ZoomOut(); event.preventDefault(); } } else if (!event.shiftKey && !event.altKey && !event.metaKey) { // Is the vertical scrollbar hidden? // https://stackoverflow.com/a/4814526/881731 if (this.container.scrollHeight <= this.container.clientHeight) { if (event.deltaY < 0) { this.PreviousPage(); event.preventDefault(); } else if (event.deltaY > 0) { this.NextPage(); event.preventDefault(); } } } } } });