pdf.js/examples/text-only/pdf2svg.js
Jonas Jenwald 8129815538 Enable the unicorn/prefer-dom-node-append ESLint plugin rule
This rule will help enforce slightly shorter code, especially since you can insert multiple elements at once, and according to MDN `Element.append()` is available in all browsers that we currently support.

Please find additional information here:
 - https://developer.mozilla.org/en-US/docs/Web/API/Element/append
 - https://github.com/sindresorhus/eslint-plugin-unicorn/blob/main/docs/rules/prefer-dom-node-append.md
2022-06-12 13:07:03 +02:00

73 lines
2.7 KiB
JavaScript

/* 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.
*/
const PDF_PATH = "../../web/compressed.tracemonkey-pldi-09.pdf";
const PAGE_NUMBER = 1;
const PAGE_SCALE = 1.5;
const SVG_NS = "http://www.w3.org/2000/svg";
pdfjsLib.GlobalWorkerOptions.workerSrc =
"../../node_modules/pdfjs-dist/build/pdf.worker.js";
function buildSVG(viewport, textContent) {
// Building SVG with size of the viewport (for simplicity)
const svg = document.createElementNS(SVG_NS, "svg:svg");
svg.setAttribute("width", viewport.width + "px");
svg.setAttribute("height", viewport.height + "px");
// items are transformed to have 1px font size
svg.setAttribute("font-size", 1);
// processing all items
textContent.items.forEach(function (textItem) {
// we have to take in account viewport transform, which includes scale,
// rotation and Y-axis flip, and not forgetting to flip text.
const tx = pdfjsLib.Util.transform(
pdfjsLib.Util.transform(viewport.transform, textItem.transform),
[1, 0, 0, -1, 0, 0]
);
const style = textContent.styles[textItem.fontName];
// adding text element
const text = document.createElementNS(SVG_NS, "svg:text");
text.setAttribute("transform", "matrix(" + tx.join(" ") + ")");
text.setAttribute("font-family", style.fontFamily);
text.textContent = textItem.str;
svg.append(text);
});
return svg;
}
async function pageLoaded() {
// Loading document and page text content
const loadingTask = pdfjsLib.getDocument({ url: PDF_PATH });
const pdfDocument = await loadingTask.promise;
const page = await pdfDocument.getPage(PAGE_NUMBER);
const viewport = page.getViewport({ scale: PAGE_SCALE });
const textContent = await page.getTextContent();
// building SVG and adding that to the DOM
const svg = buildSVG(viewport, textContent);
document.getElementById("pageContainer").append(svg);
// Release page resources.
page.cleanup();
}
document.addEventListener("DOMContentLoaded", function () {
if (typeof pdfjsLib === "undefined") {
// eslint-disable-next-line no-alert
alert("Please build the pdfjs-dist library using\n `gulp dist-install`");
return;
}
pageLoaded();
});