This obviously won't matter in practice, however it seems more "correct" to only extract the necessary number of color components rather than slicing off excess ones at the end.
The `PagesMapper` class currently makes up one third of the `src/display/display_utils.js` file size, and since its introduction it's grown (a fair bit) in size.
Note that the intention with files such as `src/display/display_utils.js` was to have somewhere to place functionality too small/simple to deserve its own file.
The user has to select some pages and then click on the "Save As" menu item in the Manage menu.
If they modify the structure of the pdf (deleted, moved, copied pages), they have to use the usual
save button.
This will ignore filenames that become effectively empty, i.e. ones that are only ".pdf" and nothing more.
*Please note:* While this passes all existing unit-tests, I don't know if this is necessarily the "correct" solution here.
Currently we essentially "duplicate" the same code for parsing the `values` and `keys` of the `searchParams`, which seems a little unnecessary.
To be able to parse the `searchParams` from the end, we currently create an Array (from the Iterator) and then reverse it before finally looping through it. Here the latter two steps can be replaced with the `Array.prototype.findLast()` method instead.
*Please note:* I completely understand if this patch is rejected, on account of being less readable than the current code.
In all cases where we currently use `Response.prototype.arrayBuffer()` the result is immediately wrapped in a `Uint8Array`, which can be avoided by instead using the newer `Response.prototype.bytes()` method; see https://developer.mozilla.org/en-US/docs/Web/API/Response/bytes
Report loading progress "automatically" when using the `PDFDataTransportStream` class, and remove the `PDFDataRangeTransport.prototype.onDataProgress` method
Currently this code expects a "url string", rather than a proper `URL` instance, which seems completely unnecessary now. The explanation for this is, as so often is the case, "historical reasons" since a lot of this code predates the general availability of `URL`.
We used a SVG string which can be pass to the Path2D ctor but it's a bit slower than
building the path step by step.
Having numerical data instead of a string will help the font data serialization.
*This is something that occurred to me when reviewing the latest PDF.js update in mozilla-central.*
Currently we duplicate essentially the same code in both the `OutputScale.prototype.limitCanvas` and `PDFPageDetailView.prototype.update` methods, which seems unnecessary, and to avoid that we introduce a new `OutputScale.capPixels` method that is used to compute the maximum canvas pixels.
This way it helps to reduce the overall canvas dimensions and make the rendering faster.
The drawback is that when scrolling, the page can be blurry in waiting for the rendering.
The default value is 200% on desktop and will be 100% for GeckoView.
Currently we lookup the `devicePixelRatio`, with fallback handling, in a number of spots in the code-base.
Rather than duplicating code we can instead add a new static method in the `OutputScale` class, since that one is now exposed in the API.
This addresses an inconsistency in the viewer, since the thumbnails don't respect the `maxCanvasPixels` option.
Note that, as far as I know, this has not lead to any bugs since the thumbnails render with a fixed (and small) width, however it really cannot hurt to address this (especially after the introduction of the `maxCanvasDim` option).
To support this a new `OutputScale`-method was added, to avoid having to duplicate code in multiple files.
Rather than modifying the "raw" dimensions of the page, we'll instead apply the `userUnit` as an *additional* scale-factor via CSS.
*Please note:* It's not clear to me if this solution is fully correct either, or if there's other problems with it, but it at least *appears* to work.
---
With these changes, the following CSS variables are now assumed to be available/set as necessary: `--total-scale-factor`, `--scale-factor`, `--user-unit`, `--scale-round-x`, and `--scale-round-y`.
The purpose of these changes is to make it more difficult to accidentally include logging statements, used during development and debugging, when submitting patches for review.
For (almost) all code residing in the `src/` folder we should use our existing helper functions to ensure that all logging can be controlled via the `verbosity` API-option.
For the `test/unit/` respectively `test/integration/` folders we shouldn't need any "normal" logging, but it should be OK to print the *occasional* warning/error message.
Please find additional details about the ESLint rule at https://eslint.org/docs/latest/rules/no-console
- Over time the number and size of these factories have increased, especially the `DOMFilterFactory` class, and this split should thus aid readability/maintainability of the code.
- By introducing a couple of new import maps we can avoid bundling the `DOMCMapReaderFactory`/`DOMStandardFontDataFactory` classes in the Firefox PDF Viewer, since they are dead code there given that worker-thread fetching is always being used.
- This patch has been successfully tested, by running `$ ./mach test toolkit/components/pdfjs/`, in a local Firefox artifact-build.
*Note:* This patch reduces the size of the `gulp mozcentral` output by `1.3` kilo-bytes, which isn't a lot but still cannot hurt.
This moves more functionality into the base-class, rather than having to duplicate that in the extending classes.
For consistency, also updates the `BaseStandardFontDataFactory` and introduces more `async`/`await` in various relevant code.
This unifies the various factory-options, since it's consistent with `CMapReaderFactory`/`StandardFontDataFactory`, and ensures that any needed parameters will always be consistently provided when creating `CanvasFactory`/`FilterFactory`-instances.
As shown in the modified example this may simplify some custom implementations, since we now provide the ability to access the `CanvasFactory`-instance used with a particular `getDocument`-invocation.
Somehow I managed to mess up the URL creation relevant to e.g. MOZCENTRAL builds, which is breaking the pending PDF.js update in mozilla-central; sorry about that!
To avoid future issues, we'll now always check if absolute filter-URLs are necessary regardless of the build-target.
This functionality is purposely limited to development mode and GENERIC builds, since it's unnecessary in e.g. the *built-in* Firefox PDF Viewer, and will only be used when a `<base>`-element is actually present.
*Please note:* We also have tests in mozilla-central that will *indirectly* ensure that relative filter-URLs work as intended in the Firefox PDF Viewer, see https://searchfox.org/mozilla-central/source/toolkit/components/pdfjs/test/browser_pdfjs_filters.js
---
To test that the issue is fixed, the following code can be used:
```html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<base href=".">
<title>base href (issue 18406)</title>
</head>
<body>
<ul>
<li>Place this code in a file, named `base_href.html`, in the root of the PDF.js repository</li>
<li>Run <pre>npx gulp dist-install</pre></li>
<li>Run <pre>npx gulp server</pre></li>
<li>Open <a href="http://localhost:8888/base_href.html">http://localhost:8888/base_href.html</a> in a browser</li>
<li>Compare rendering with <a href="http://localhost:8888/web/viewer.html?file=/test/pdfs/issue16287.pdf">http://localhost:8888/web/viewer.html?file=/test/pdfs/issue16287.pdf</a></li>
</ul>
<canvas id="the-canvas" style="border: 1px solid black; direction: ltr;"></canvas>
<script src="/node_modules/pdfjs-dist/build/pdf.mjs" type="module"></script>
<script id="script" type="module">
//
// If absolute URL from the remote server is provided, configure the CORS
// header on that server.
//
const url = '/test/pdfs/issue16287.pdf';
//
// The workerSrc property shall be specified.
//
pdfjsLib.GlobalWorkerOptions.workerSrc =
'/node_modules/pdfjs-dist/build/pdf.worker.mjs';
//
// Asynchronous download PDF
//
const loadingTask = pdfjsLib.getDocument(url);
const pdf = await loadingTask.promise;
//
// Fetch the first page
//
const page = await pdf.getPage(1);
const scale = 1.5;
const viewport = page.getViewport({ scale });
// Support HiDPI-screens.
const outputScale = window.devicePixelRatio || 1;
//
// Prepare canvas using PDF page dimensions
//
const canvas = document.getElementById("the-canvas");
const context = canvas.getContext("2d");
canvas.width = Math.floor(viewport.width * outputScale);
canvas.height = Math.floor(viewport.height * outputScale);
canvas.style.width = Math.floor(viewport.width) + "px";
canvas.style.height = Math.floor(viewport.height) + "px";
const transform = outputScale !== 1
? [outputScale, 0, 0, outputScale, 0, 0]
: null;
//
// Render PDF page into canvas context
//
const renderContext = {
canvasContext: context,
transform,
viewport,
};
page.render(renderContext);
</script>
</body>
</html>
```
and implement then in using some SVG filters and composition.
Composing in using destination-in in order to multiply RGB components by
the alpha from the mask isn't perfect: it'd be a way better to natively have
alpha masks support, it induces some small rounding errors and consequently
computed RGB are approximatively correct.
In term of performance, it's a real improvement, for example, the pdf in
issue #17779 is now rendered in few seconds.
There are still some room for improvement, but overall it should be a way
better.
