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| author | Tor Andersson <tor.andersson@artifex.com> | 2018-09-10 18:18:49 +0200 |
|---|---|---|
| committer | Tor Andersson <tor.andersson@artifex.com> | 2018-10-23 17:23:59 +0200 |
| commit | 8ebce9c149112d59552ed530361f80372455fdb2 (patch) | |
| tree | ebc90eb93345d1b3a77841ed2a92e56a4c1b1baf /platform/wasm/readme.html | |
| parent | ddd00f62888c908c84932c2a92a0c2d195b26c36 (diff) | |
| download | mupdf-8ebce9c149112d59552ed530361f80372455fdb2.tar.xz | |
Add Emscripten / WebAssembly build.
Requires Linux (or possibly MacOS X) and an installed emsdk to build.
Diffstat (limited to 'platform/wasm/readme.html')
| -rw-r--r-- | platform/wasm/readme.html | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/platform/wasm/readme.html b/platform/wasm/readme.html new file mode 100644 index 00000000..5d6b97ed --- /dev/null +++ b/platform/wasm/readme.html @@ -0,0 +1,135 @@ +<!DOCTYPE html> +<html> +<head> +<title>MuPDF / WebAssembly</title> +<meta charset="utf-8"> +<style> +pre,dl{margin-left:2em;} +dt{margin-top:0.5em;font-family:monospace} +</style> +</head> +<body> + +<h1>MuPDF WebAssembly</h1> + +<h2>Building</h2> + +<p> +The WebAssembly build has only been tested on Linux at the moment. +If you use any other platform, you are on your own. + +<p> +In order to build this you will need to install the +<a href="https://kripken.github.io/emscripten-site/docs/getting_started/downloads.html">Emscripten SDK</a> +in <tt>/opt/emsdk</tt>. +If you install it elsewhere, you will need to edit the platform/wasm/build.sh +script to point to the appropriate location. + +<p> +From the MuPDF project, you can run <tt>make wasm</tt> to build the WebAssembly +library. The results of the build are a libmupdf.wasm binary and +libmupdf.js script, placed in platform/wasm/. + +<p> +In order to build a web application based on MuPDF, you will need to copy +these two files and make them available to your page. + +<p> +The libmupdf.wasm binary is quite large, because it contains not only the MuPDF +library code, but also the 14 core PDF fonts, various CJK mapping resources, +and ICC profiles. In order to keep it as small as possible, it is built with a +minimal features set that does not include CJK fonts, EPUB support, etc. + +<h2>Using</h2> + +<p> +The example script in platform/wasm/view.html shows how to use the +MuPDF WebAssembly library. + +<p> +The first part is including the libmupdf.js script, which pulls in +and instantiates the WebAssembly module: + +<pre> +<script src="libmupdf.js"></script> +</pre> + +<p> +MuPDF uses the Emscripten virtual file system to load a document, so you will +need to seed it with the file you want to view in a Module.preRun +callback function: + +<pre> +<script> +Module.preRun = function () { + FS.createPreloadedFile(".", "input.pdf", "input.pdf", true, false); +} +</script> +</pre> + +<p> +When the filesystem has finished preloading the file data and initialized the +code, it will call the Module.postRun callback. From here, you can +use the 'mupdf' object to call various functions to open the document and +render pages into various formats. + +<dl> +<dt>mupdf.openDocument(filename) +<dd>Open a document and return a handle. +<dt>mupdf.freeDocument(doc) +<dd>Free a document and its associated resources. +<dt>mupdf.documentTitle(doc) +<dd>Return the document title as a string. +<dt>mupdf.documentOutline(doc) +<dd>Return a DOM element containing the table of contents formatted as +an unordered HTML list with links to pages using anchor fragments "#page%d". +<dt>mupdf.countPages(doc) +<dd>Return the number of pages in the document. +<dt>mupdf.pageWidth(doc, page, dpi) and mupdf.pageHeight(doc, page, dpi) +<dd>Return the dimensions of a page. Page numbering starts at 1. +<dt>mupdf.drawPageAsPNG(doc, page, dpi) +<dd>Render the page and return a PNG image formatted as a data URI, +suitable for using as an image source attribute. +<dt>mupdf.pageLinks(doc, page, dpi) +<dd>Retrieve an HTML string describing the links on a page, +suitable for including as the innerHTML of an image map. +<dt>mupdf.drawPageAsSVG(doc, page) +<dd>Return a string with the contents of the page in SVG format. +<dt>mupdf.drawPageAsHTML(doc, page) +<dd>Return a string with the contents of the page in HTML format, +using absolute positioned elements. +</dl> + +<h2>Example</h2> + +<p> +Here is a very simple example of loading a document and drawing its first page: + +<pre> +<!DOCTYPE html> +<html> +<head> +<script src="libmupdf.js"></script> +<script> +Module.preRun = function () { + FS.createPreloadedFile(".", "input.pdf", "input.pdf", true, false); +} +Module.postRun = function () { + var DPI = 96; + var doc = mupdf.openDocument("input.pdf"); + var img = document.getElementById("page1"); + img.src = mupdf.drawPageAsPNG(doc, 1, DPI); + var map = document.getElementById("page1map"); + map.innerHTML = mupdf.pageLinks(doc, 1, DPI); +} +</script> +</head> +<body> +<img id="page1" usemap="#page1map"> +<map id="page1map" name="page1map"></map> +</body> +</html> +</pre> + +</body> +</html> |