With the recently added OpenJPEG no-wasm fallback we need to send the `wasmUrl` option to the worker-thread *regardless* of the value of the `useWorkerFetch` option, since the fallback won't work if we don't have a URL to `import` it from.
For consistency the code is re-factored to always send the factory-urls to the worker-thread, and simply check the `useWorkerFetch` option there instead.
Also, as a follow-up to PR 19525, introduce a new `useWasm` option that can be used in e.g. browser-tests to forcibly disable WebAssembly usage.
Currently we modify the EXIF-block in place, which may end up "breaking" the JPEG-data of the original PDF document since e.g. saving it from the viewer no longer contains the real EXIF-block.
Hence the EXIF-block replacement is moved into the `JpegStream` class, such that we can copy the data before doing the replacement.
During the XRef stream parsing we're attempting to lookup an entry that hasn't yet been found, since parsing is currently running, and given that we'd also cache free/missing XRef entries we'd then return an incorrect value during normal PDF parsing.
The simplest solution here is to just not cache free/missing XRef entries, since a properly generated PDF document shouldn't be trying to access objects it doesn't contain.
Furthermore, the amount of "extra" parsing now needed for such XRef entries shouldn't be significant enough to be an issue.
Currently this rule is disabled in a number of spots across the code-base, and unless absolutely necessary we probably shouldn't disable linting, so let's just update the code to fix all the outstanding cases.
If either of the factory-urls are missing or invalid, the fallback value would currently become `useWorkerFetch === null`.
While that is obviously a falsy value, which means that the code still works as intended, we should ensure that this is consistent.
- Use `TypedArray.prototype.set()` rather than a manual loop when building the `key`.
- Use an existing local variable to avoid re-computing the length of the `encryptionKey`.
It's now pretty common that we only want to close a `dialog` *if* it's currently active, to avoid throwing errors, and this new method provides a shorter and more convenient way to achieve that.
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`.
While investigating a bug, that I've not yet had time to fully investigate and report, I found that if there's ever an error thrown from the `Autolinker` class it'll prevent the annotationEditorLayer from rendering *and* the renderTask itself will be treated as having failed.
Given that most inferred links will overlap existing LinkAnnotations, creating a lot of unused `borderStyle` objects seem unnecessary.
Hence we can move that into the `AnnotationLayer.prototype.addLinkAnnotations` method instead, which also allows us to slightly reduce the API-surface.
*Note:* For the issue mentioned on Matrix it'll obviously still make sense to improve the regular expression to detect more URL edge-cases.
However it occurred to me that even once that particular case is fixed there'll always be a risk that inferred links could overlap, and effectively block, the actual LinkAnnotations.
Hence this patch removes the URL comparison to ensure that overlapping inferred links will always be ignored.
This patch updates the minimum supported browsers as follows:
- Google Chrome 110, which was released on 2023-02-07; see https://chromereleases.googleblog.com/2023/02/stable-channel-update-for-desktop.html
Note that nowadays we usually try, where feasible and possible, to support browsers that are about two years old. By limiting support to only "recent" browsers we reduce the risk of holding back improvements of the *built-in* Firefox PDF Viewer, and also (significantly) reduce the maintenance/support burden for the PDF.js contributors.
*Please note:* As always, the minimum supported browser version assumes that a `legacy`-build of the PDF.js library is being used; see https://github.com/mozilla/pdf.js/wiki/Frequently-Asked-Questions#faq-support
Currently we have three separate and virtually identical message handlers for this data, which can easily be combined into a single message handler instead.
With recent changed made to the GitHub issues-UI the "Blank issue" alternative is now showing up quite prominently, which can easily negate the point of our bug/feature templates and lead to incomplete issues being filed.
Given that we now have a few different factory-url parameters, we introduce a helper function for parsing them.
*Please note:* These parameters have always been documented as requiring a trailing slash[1], which we can now easily enforce during the `getDocument`-call.
---
[1] I recall that we've occasionally seen issues because users miss that detail, and the new Error should hopefully be more easily actionable than one thrown during rendering/parsing.
This CSS feature is now available in *most* browsers that we support, with old Chromium-based browsers being the only exception; please see https://developer.mozilla.org/en-US/docs/Web/CSS/color_value/color-mix#browser_compatibility
From this data we see that the feature in question has been supported since Chrome 111, which was released on 2023-03-01 (i.e. almost two years ago).
Please note that we've never guaranteed that all features and functionality will be available in the oldest supported browsers.
Furthermore, even with the `color-mix` fallback removed PopupAnnotations will still function just as before but may render with the default color (defined in the CSS-file) rather than the one specified in the PDF document.
At the time of PR 12896 the `fontBoundingBox{Ascent, Descent}` properties were not yet available by default in Fírefox, however that's no longer the case since Firefox 116; please see https://bugzilla.mozilla.org/show_bug.cgi?id=1801198.
Hence this patch which replaces the "full" fallback with a warning and uses the `ascent`/`descent` values from the fonts in the PDF document (as we did previously). Obviously the TextLayer won't look as good in that case, but it's a simpler and shorter solution.
Currently we're manually computing the width/height of the /Rect-entry in a number of spots throughout the worker-thread Annotation code, which these new getters help avoid.
Currently we're initializing the image-options for every page, which seems unnecessary since it should suffice to do that once per document.
Also, changes the `BasePdfManager` constructor to improve readability/documentation a little bit.
Steps to reproduce this in `master`:
1. Open https://mozilla.github.io/pdf.js/web/viewer.html
2. Use the "Open"-button (in the secondaryToolbar), or drag-and-drop, to load another PDF document.
3. Enable the highlight-editor.
4. Try to pick a new colour.
Note how it's no longer possible to change the default highlight-colour.
The reason for this is that we're only initializing the viewer-toolbar `ColorPicker` *once*, which doesn't work since every PDF document gets its own `AnnotationEditorUIManager`-instance. To address this we simply need to re-initialize the viewer-toolbar `ColorPicker`, and note that this patch won't affect the Firefox PDF Viewer.
With the changes in PR 18843 the `AnnotationEditorUIManager.prototype.updateMode` method is now asynchronous, which we need to take into account when dispatching the "annotationeditormodechanged" event.
After PR 2317, which landed in 2012, we'd immediately clean-up after rendering for pages with large image resources. This had the effect that re-rendering, e.g. after zooming, would force us to re-parse the entire page which could easily lead to bad performance.
In PR 16108, which landed in 2023, we tried to lessen the impact of that by slightly delaying clean-up however that's obviously not a perfect solution (and it increased the complexity of the relevant code).
Furthermore, the condition for this "immediate" clean-up seems a bit arbitrary to me since a page could easily contain a large number of smaller images whose total size vastly exceeds the threshold.
Hence this patch, which suggests that we remove the conditional and delayed clean-up after rendering. Compared to the situation back in 2012, a number of things have improved since:
- We have *multiple* caches for repeated image-resources on the worker-thread[1], which helps reduce overall memory usage and improves performance.
- We downsize huge images on the worker-thread, which means that the images we're using on the main-thread cannot be arbitrarily large.
- The amount of available RAM on devices should be a lot higher, since more than a decade has passed.
A future improvement here, for more resource constrained environments, could be to instead clean-up when actually needed using e.g. `WeakRef`s (see issue 18148).
---
[1] More specifically:
- `LocalImageCache`, which caches image-data by /Name and /Ref on the `PartialEvaluator.prototype.getOperatorList` level.
- `RegionalImageCache`, which caches image-data by /Ref on the `PartialEvaluator`-instance (i.e. at the page) level.
- `GlobalImageCache`, which caches image-data by /Ref globally at the document level.
Code in the `web/` folder cannot import directly from the `src/` folder, since that could result in most (or all) main-thread code being bundled into the viewer, and must rather be imported via the `pdfjs-lib` alias.
Let's use ESLint to help enforce this, please find additional details in https://github.com/import-js/eslint-plugin-import/blob/main/docs/rules/no-restricted-paths.md
- Most of the these are only used in the `src/display/api.js` file, and this leads to slightly shorter code.
- A number of unit-tests need a `BaseCanvasFactory`-instance, however that one is available through the `PDFDocumentProxy`-instance nowadays.
- For other unit-tests the remaining necessary default Factory-definitions can be moved into the `test/unit/test_utils.js` file.
This prepares for a future where we're using more than one wasm-file, originating in different `external/`-folders, by extending the existing `gulp.watch` usage.
The following diff illustrates how to add more entries:
```diff
diff --git a/gulpfile.mjs b/gulpfile.mjs
index 0e0a5a1ac..1502755be 100644
--- a/gulpfile.mjs
+++ b/gulpfile.mjs
@@ -655,6 +655,10 @@ function createWasmBundle() {
base: "external/openjpeg",
encoding: false,
}),
+ gulp.src(["external/foobar/*.wasm"], {
+ base: "external/foobar",
+ encoding: false,
+ }),
]);
}
@@ -2125,7 +2129,7 @@ gulp.task(
},
function watchWasm() {
gulp.watch(
- "external/openjpeg/*",
+ ["external/openjpeg/*", "external/foobar/*"],
{ ignoreInitial: false },
gulp.series("dev-wasm")
);
```
Jonas Jenwald