When rendering big PDF pages at high zoom levels, we currently fall back
to CSS zoom to avoid rendering canvases with too many pixels. This
causes zoomed in PDF to look blurry, and the text to be potentially
unreadable.
This commit adds support for rendering _part_ of a page (called
`PDFPageDetailView` in the code), so that we can render portion of a
page in a smaller canvas without hiting the maximun canvas size limit.
Specifically, we render an area of that page that is slightly larger
than the area that is visible on the screen (100% larger in each
direction, unless we have to limit it due to the maximum canvas size).
As the user scrolls around the page, we re-render a new area centered
around what is currently visible.
This base class contains the generic logic for:
- Creating a canvas and showing when appropriate
- Rendering in the canvas
- Keeping track of the rendering state
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.
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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.
Automatically detect links in the text content of a file and automatically
generate link annotations at the appropriate locations to achieve
automatic link detection and hyperlinking.
It fixes#19239.
When the canvas isn't existing the editor has no image: it's fine because the editor is invisible.
Once it's made visible, the canvas is set when the annotation layer has been rendered.
Instead of conditionally checking if the `.cavnasWrapper` already
has a child element and then inserting the `canvas` before it, we can
use `.prepend` which always injects the new element as the first
child.
While drawing, in zooming fast enough, it's possible, intermittently, to have the canvas
after the svg which makes the svg invisible.
So this patch makes sure to have the canvas at the right position.
Converting errors to string drops their stack trace, making it more
difficult to debug their actual reason. We can instead pass the error
objects as-is to console.warn/error, so that Firefox/Chrome devtools
will show both the stack trace of the console.warn/error call, and the
original stack trace of the error.
This commit also enables the `unicorn/no-console-spaces` ESLint rule,
which avoids accidental extra spaces when passing multiple parameters to
`console.*` methods.
The idea is to insert a span in the text layer with an aria-role set to img
and use the bounding box provided by the attribute field in the tag dict in
order to have non-null dimensions for the image to make it "visible".
Right now, editable annotations are using their own canvas when they're drawn, but
it induces several issues:
- if the annotation has to be composed with the page then the canvas must be correctly
composed with its parent. That means we should move the canvas under canvasWrapper
and we should extract composing info from the drawing instructions...
Currently it's the case with highlight annotations.
- we use some extra memory for those canvas even if the user will never edit them, which
the case for example when opening a pdf in Fenix.
So with this patch, all the editable annotations are drawn on the canvas. When the
user switches to editing mode, then the pages with some editable annotations are redrawn but
without them: they'll be replaced by their counterpart in the annotation editor layer.
Ensure that we never round the canvas dimensions above `maxCanvasPixels`
by rounding them to the preceeding multiple of the display ratio rather
than the succeeding one.
The `setTextContentSource` functionality is very old code, and was introduced years ago together with streaming of textContent.
By moving the `streamTextContent`-call into the `TextLayerBuilder` class we collect more functionality in one place and slightly reduce the amount of code needed.
This is very old code, and predates e.g. the introduction of JavaScript classes, which creates unnecessarily unwieldy code in the viewer.
By introducing a new `TextLayer` class in the API, similar to how e.g. the `AnnotationLayer` looks, we're able to keep most parameters on the class-instance itself. This removes the need to manually track them in the viewer, and simplifies the call-sites.
This also removes the `numTextDivs` parameter from the "textlayerrendered" event, since that's only added to support default-viewer functionality that no longer exists.
Finally we try, as far as possible, to polyfill the old `renderTextLayer` and `updateTextLayer` functions since they are exposed in the library API.
For *simple* invocations of `renderTextLayer` the behaviour should thus be the same, with only a warning printed in the console.
If a user manually calls `PDFPageView.prototype.update()` with a `drawingDelay`-option then it'll always be necessary to re-call the method *without* a delay afterwards, regardless of the `maxCanvasPixels`-value (e.g. even when CSS-only zooming is used).
With recent improvements to the `AppOptions`, e.g. with better validation and testing, one remaining "annoyance" is the `compatibilityParams` handling. Especially since there's only *a single* parameter left, limited to GENERIC builds.
To further reduce the amount of unnecessary code in e.g. the Firefox PDF Viewer, we can move the `compatibilityParams` handling into the user-options instead since that keeps the previous precedence order between default/user-options.
Previously we'd simply export this directly from `web/app_options.js`, which meant that it'd be technically possible to *accidentally* modify the `compatibilityParams` Object when accessing it.
To avoid this we instead introduce a new `AppOptions`-method that is used to lookup data in `compatibilityParams`, which means that we no longer need to export this Object.
Based on these changes, it's now possible to simplify some existing code in `AppOptions` by taking full advantage of the nullish coalescing (`??`) operator.
- Ensure that localization works in the GENERIC viewer, even if the necessary locale files cannot be loaded.
This was the behaviour prior to the introduction of Fluent, and it seems worthwhile to keep that (especially since we already bundle the en-US strings anyway).
- Let the `GenericL10n`-implementation use the *bundled* en-US strings directly when no language is provided.
- Remove the `NullL10n`-implementation, and simply fallback to `GenericL10n`, to reduce the maintenance burden of viewer-components localization.
- Indirectly, given the previous point, stop exporting `NullL10n` in the viewer-components since it's now removed.
Note that it was never really intended to be used directly and only existed as a fallback.
*Please note:* This doesn't affect the Firefox PDF Viewer, thanks to the use of import maps.
In order to do that we must change the text layer opacity to 1 but
it has several implications:
- the selection color must have an alpha component,
- the background color of the span used for highlighted words
must have an alpha component either, but now the opacity is 1
we can use some backdrop-filters in HCM making the highlighted
words more visible.
- fix a regression caused by #17196: the css variable --hcm-highlight-filter
has to live under the #viewer element because in HCM it's overwritten
by js at this level, hence links annotations for example didn't
have the right colors when hovered.
The system locale (used in OffscreenCanvas) can be different from the one guessed by Fluent,
consequently, in order to avoid any mismatch, we just use an attached canvas element.
The original issue can easily be reproduced locally in adding a lang="ja" in viewer.html
(or with an other language for Japanese users).
Note that we must append the textLayer to the DOM *before* enabling the `highlighter` and `accessibilityManager`, to avoid breaking e.g. a pending searching operation.
The least invasive solution, that I was able to come up with, is to introduce a new `TextLayerBuilder` callback-function for this purpose.
After PR 17177 the interface of `XfaLayerBuilder` is now inconsistent, since whether or not we directly append the xfaLayer to the DOM now depends on the rendering intent.
Looking at the `PDFThumbnailView.setPageLabel` method you'll see that we update e.g. the "aria-label" of the thumbnail-image for documents that contain (valid) pageLabels.
This isn't done in `PDFPageView`, which seems inconsistent, hence this patch.
This patch changes almost all viewer-components[1] to use "data-l10n-id"/"data-l10n-args" for localization, which means that in many cases we no longer need to pass around the `L10n`-instance any more.
One part of the code-base where the `L10n`-instance is still being used "directly" is the AnnotationEditors, however while it might be possible to convert (most of) that code as well that's not attempted in this patch.
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[1] The one exception is the `PDFDocumentProperties` dialog, since the way it's currently implemented makes that less straightforward to fix without a lot of code changes.
*Please note:* These changes only affect the GENERIC build, since `NullL10n` is only a stub elsewhere (see PR 17135).
After the changes in PR 17115, which modernized and improved l10n-handling, the `NullL10n`-implementation is no longer a good fallback for the "proper" `L10n`-classes.
To improve this situation, especially for the *standalone* viewer-components, this patch makes the following changes:
- Let the `NullL10n`-implementation extend an actual `L10n`-class, which is constant and lazily initialized, to ensure that it works *exactly* like the "proper" ones.
- Automatically bundle the "en-US" l10n-strings in the build, via the pre-processor, such that we don't need to remember to manually update them.
- Ensure that the *standalone* viewer-components register their DOM-elements for translation, similar to the default viewer, since this will allow future code improvements by using "data-l10n-id"/"data-l10n-args" in most (if not all) parts of the viewer.
- Remove the `NullL10n` from the `AnnotationLayer`, to avoid affecting bundle size too much.
For third-party users that access the `AnnotationLayer`, as exposed in the main PDF.js library, they'll now need to *manually* register it for translation. (However, the *standalone* viewer-components still works given the point above.)
