This code was added all the way back in PR 6698, almost seven years ago, for backwards compatibility reasons. At this point in time, it seems that we can remove that since:
- We have more fine-grained "UnsupportedFeature" reporting elsewhere in the worker-thread code nowadays.
- The GetOperatorList-handling is now using `ReadableStream`s, which means that errors are being forwarded to the main-thread anyway.
- We're also no longer displaying a notification-bar, in the *built-in* Firefox PDF Viewer, for any of these "UnsupportedFeature" messages.
*Please note:* I don't really know what I'm doing here, however the patch appears to fix the referenced issue when comparing the rendering with Adobe Reader (with the caveat that I don't speak the language in question).
Note how after having found the "%PDF-" prefix we then read both the prefix and the version in the loop, only to then remove the prefix at the end.
It seems better to instead advance the stream position past the "%PDF-" prefix, and then read only the version data.
Finally the loop-condition can also be simplified slightly, to further clean-up some very old code.
*Fixes a regression from PR 15246, sorry about that!*
The return value of all `Annotation.getOperatorList` methods was changed in PR 15246, however I missed updating the error code-path in `Page.getOperatorList` which thus breaks all operatorList-parsing for pages with corrupt Annotations.
Looking at the code on the worker-thread, there doesn't appear to be any particular reason for placing *some* of the properties in a `source`-object when sending them with "GetDocRequest".
As is often the case the explanation for this structure is rather "for historical reasons", since originally we simply sent the `source`-object as-is. Doing that was obviously a bad idea, for a couple of reasons:
- It makes it less clear what is/isn't actually needed on the worker-thread.
- Sending unused properties will unnecessarily increase memory usage.
- The `source`-object may contain unclonable data, which would break the library.
Rather than sending all of these parameters individually and then grouping them together on the worker-thread, we can simply handle that in the API instead.
I noticed the 256 % 3 (which is equal to 1) so I slighty simplify the code.
The sum of the 16 Uint8 doesn't exceed 2^12, hence we can just take the
sum modulo 3.
This patch first of all makes `isOffscreenCanvasSupported` configurable, defaulting to `true` in browsers and `false` in Node.js environments, with a new `getDocument` parameter. While you normally want to use this, in order to improve performance, it should still be possible for users to control it (similar to e.g. `isEvalSupported`).
The specific problem, as reported in issue 14952, is that the SVG back-end doesn't support the new ImageMask data-format that's introduced in PR 14754. In particular:
- When the SVG back-end is used in Node.js environments, this patch will "just work" without the user needing to make any code changes.
- If the SVG back-end is used in browsers, this patch will require that `isOffscreenCanvasSupported: false` is added to the `getDocument`-call.
*Please note:* The referenced issue is the only mention that I can find, in either GitHub or Bugzilla, of "GoToE" actions.
Hence why I've purposely settled for a very simple, and partial, "GoToE" implementation to avoid complicating things initially.[1] In particular, this patch only supports "GoToE" actions that references the /EmbeddedFiles-dict in the PDF document.
See https://web.archive.org/web/20220309040754if_/https://www.adobe.com/content/dam/acom/en/devnet/pdf/pdfs/PDF32000_2008.pdf#G11.2048909
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[1] Usually I always prefer having *real-world* test-cases to work with, whenever I'm implementing new features.
Note that this PR only adds the "underscore"-variant of *actually existing* ligatures, however the referenced PDF document also uses a couple of non-standard ones (e.g. `ft`, `Th`, and `fh`) that we cannot easily support without larger changes (since they don't have official Unicode-entries).
Given that it's clearly the PDF document, and its fonts, that's the culprit here it's not entirely clear to me that we actually want to attempt a larger refactoring/rewriting of the `glyphlist.js` code, assuming it's even generally possible. Especially when this patch alone already improves our copy-paste behaviour when compared to both Adobe Reader and PDFium, and that this is only the *second* time this sort of bug has been reported.
OperatorList.addOp can trigger a flush if it's required, hence the values passed to it must
be correctly initialized in order to avoid some wrong values in the renderer.
Because of that a clip path was considered as empty, nothing was clipped, hence the wrong
rendering in bug 1791583.
Since there are no script engine with XFA, the FormCalc parser is not used irl.
The bug @nmtigor noticed was hidden by another one (the wrong check on `match`).
Most of the `String.prototype.search` call-sites found throughout the code-base is actually not necessary, since we usually only want a *boolean*, and those can be replaced with `RegExp.prototype.test` instead.
*Please note:* This is only a, hopefully generally helpful, work-around rather than a proper solution to issue 15292.
There's something that's "special" about the Type1 fonts in the referenced PDF document, since we don't manage to find any actual font programs and thus cannot render anything.
Given that it shouldn't make sense for a Type1 font program to ever be empty, since that means that there's no glyph-data to render, we simply fallback to a standard font to at least try and render *something* in these rare cases.
Given that the change in PR 13393 was slightly speculative, given the lack of test-cases, let's just revert part of that to fix the referenced issue.
Based on a quick look at old issues and existing test-cases, it seems that most (if not all) PDF documents that benefit from using the font-data in this way lack any /ToUnicode maps which should mean that they're unaffected by these changes.
Note that this patch implements the `SetOCGState`-handling in `PDFLinkService`, rather than as a new method in `OptionalContentConfig`[1], since this action is nothing but a series of `setVisibility`-calls and that it seems quite uncommon in real-world PDF documents.
The new functionality also required some tweaks in the `PDFLayerViewer`, to ensure that the `layersView` in the sidebar is updated correctly when the optional-content visibility changes from "outside" of `PDFLayerViewer`.
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[1] We can obviously move this code into `OptionalContentConfig` instead, if deemed necessary, but for an initial implementation I figured that doing it this way might be acceptable.
Apparently this is implemented in e.g. Adobe Reader, and the specification does support it, however it cannot be commonly used in real-world PDF documents since it took over ten years for this feature to be requested.
Given that the code is written with JavaScript module-syntax, none of this functionality will "leak" outside of this file with these change.
By removing this closure the file-size is decreased, even for the *built* `pdf.worker.js` file, since there's now less overall indentation in the code.
Given that the code is written with JavaScript module-syntax, none of this functionality will "leak" outside of this file with these changes.
For e.g. the `gulp mozcentral` command the *built* `pdf.worker.js` file-size decreases `~2 kB` with this patch, and most of the improvement comes from having less overall indentation in the code.
Given that the code is written with JavaScript module-syntax, none of this functionality will "leak" outside of this file with these changes.
By removing this closure the file-size is decreased, even for the *built* `pdf.worker.js` file, since there's now less overall indentation in the code.
By doing this in the worker-thread this code will only need to run *once*, whereas currently re-rendering of a page forces this to be repeated (e.g. after it's been scrolled out-of-view and then back into view again).
An annotation doesn't have to be in the text flow, hence it's likely a bad idea
to insert its text in the text layer. But the text must be visible from a screen
reader point of view so it must somewhere in the DOM.
So with this patch, the text from a FreeText annotation is extracted and added in
a div in its HTML counterpart, and with the patch #15237 the text should be visible
and positioned relatively to the text flow.
To improve performance of the sidebar we use the page-canvases to generate the thumbnails whenever possible, since that avoids unnecessary re-rendering when the sidebar is open. This works generally well, however there's an old problem in PDF documents that contain interactive forms (when those are enabled): Note how the thumbnails become partially (or fully) blank, since those Annotations are not included in the OperatorList.[1]
We obviously want to keep using the `PDFThumbnailView.setImage`-method for most documents, however we need a way to skip it only for those pages that contain interactive forms.
As it turns out it's unfortunately not all that simple to tell, after the fact, from looking only at the OperatorList that some Annotations were skipped. While it might have been possible to try and infer that in the viewer, it'd not have been pretty considering that at the time when rendering finishes the annotationLayer has not yet been built.
The overall simplest solution that I could come up with, was instead to include a *summary* of the interactive form-state when doing the final "flushing" of the OperatorList and expose that information in the API.
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[1] Some examples from our test-suite: `annotation-tx2.pdf` where the thumbnail is completely blank, and `bug1737260.pdf` where the thumbnail is missing the "buttons" found on the page.
Currently some `OPS.beginAnnotation` arguments will contain a `Number` value for the `isUsingOwnCanvas`-parameter, or in some cases an `undefined` value, which is inconsistent from an API perspective.
In the referenced PDF document the fonts have /CIDToGIDMap-entries that cannot be loaded. Hence, only when `ignoreErrors` is set, we'll now ignore these corrupt /CIDToGIDMap-entries and fallback to simply assume that no such data is available.
Given that this is *clearly* a case of a corrupt PDF document, there's no guarantee that this will "fix" things in the general case since a /CIDToGIDMap may be *required* in order for some composite fonts to render correctly. However, attempting to render *something* is surely better than skipping a font altogether.
Note that these cases, which are all in older code, were found using the [`unicorn/no-for-loop`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/main/docs/rules/no-for-loop.md) ESLint plugin rule.
However, note that I've opted not to enable this rule by default since there's still *some* cases where I do think that it makes sense to allow "regular" for-loops.
Note how we currently throw a "raw" Error, which is problematical since all of the `PartialEvaluator.loadFont` call-sites expect a Promise to be returned. Furthermore, this also means that we don't benefit from the fallback code-path that now exists below.
*Please note:* Unfortunately I don't have a test-case that fails without this patch, since it's something I happened to notice when reading the code while working on another patch.
This extends PR 13461, by also building a fallback bounding box for Type3 fonts that contain a much too small /FontBBox-entry.
*Please note:* While this patch improves things overall, copy-and-pasting still doesn't work perfectly for this document. In particular the lowercase letter "c" cannot be selected/copied, however this can be reproduced in both Adobe Reader and PDFium (in Google Chrome) too, which is caused by a lack of proper /ToUnicode-data in the PDF document.
- As in the annotation layer, use percent instead of pixels as unit;
- handle the rotation of the editor layer in allowing editing when rotation
angle is not zero;
- the different editors are rotated counterclockwise in order to be usable
when the main page is itself rotated;
- add support for saving/printing rotated editors.
Given that Annotations can also have an `OC`-entry, we need to take that into account when generating their operatorLists.
Note that in order to simplify the patch the `getOperatorList`-methods, for the Annotation-classes, were converted to be `async`.
- the annotations must be rendered in the same order as the chronological one.
- fix a bug in document.js which avoids to read a saved pdf correctly in Acrobat:
there is no need to reset the xref state: it's done in worker.js once everything
has been saved.
- Let the `Page.save`-method filter out "empty" entries, similar to the `Page._parsedAnnotations`-getter, since that on its own already simplifies the "SaveDocument"-handler a tiny bit.
- The existing `reduce` and `concat` construction isn't exactly a wonder of readability :-)
Thanks to modern JavaScript features it should be possible to replace all of this with `Array.prototype.flat()` instead, which at least to me feels a lot easier to understand.
There are obviously cases where using `concat` makes perfect sense, since that method doesn't change any of the existing Arrays; see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/concat
However, in a few cases throughout the code-base that's not an issue and using `concat` only leads to unnecessary intermediate allocations. With modern JavaScript we can thus replace those with a combination of `push` and spread-syntax, which wasn't originally possible when the code was written.
- each annotation has its coordinates/dimensions expressed in percentage,
hence it's correctly positioned whatever the scale factor is;
- the font sizes are expressed in percentage too and the main font size
is scaled thanks a css var (--scale-factor);
- the rotation is now applied on the div annotationLayer;
- this patch improve the rendering of some strings where the glyph spacing
was not correct (it's a Firefox bug);
- it helps to simplify the code and it should slightly improve the update of
page (on zoom or rotation).
This appears to be a Microsoft-specific version of the regular Arial font, hence we simply map this to Helvetica in the same way that we treat many other Arial-named fonts.
This only adds the minimum entries required in order to render the referenced document correctly, rather than trying to support "all" Hebrew glyphs, to ensure that all lines in `getGlyphMapForStandardFonts` are covered by tests.
After the changes in PR 14998, these operators are now no-ops in the `src/display/canvas.js` code and should no longer be necessary.
Given that `beginAnnotations`/`endAnnotations` are not in the PDF specification, but are rather *custom* PDF.js operators, it seems reasonable to stop using them now that they've become no-ops.
In the "no fontSize available" code-path, in the `ChoiceWidgetAnnotation._getAppearance` method, we don't provide the necessary second argument when calling the `_getTextWidth`-method which will cause errors to be thrown.
This method/function was added only for the `gulp image_decoders`-builds, and is completely unused elsewhere (e.g. in the Firefox PDF Viewer).
While this only reduces the size of the *built* `pdf.worker.js` file by a little over 1 kB, it can't hurt to remove completely unused code from the "normal" builds.
- right now we're using the font size from the pdf itself but we use an other font
in the annotation layer. So this size doesn't really make sense and leads to bad
rendering (see pdf in #14928);
- use a sans-serif font for the fields containing text (fix issue #14736);
- remove useless padding in text-based fields (fix issue #14301);
- text fields allow/disallow scrolling bars (see bit 24 in Ff entry), so use this
value to hide/show scrollbars in annotation layer.
In the `src/display/canvas.js` code the `d1` operator will be used to set the clipping region, and it obviously cannot be empty since that prevents the Type3-glyph from rendering.
Also, the patch removes an outdated comment; refer to PR 12718.
This limits the heuristics for handling of incomplete path operators, see PR 9838, to only apply to *sequences* of such operators. In practice a couple of invalid path operators are (hopefully) unlikely to completely break rendering, whereas a sequence of them will easily lead to fairly chaotic rendering artifacts.
The current `lastModified`-getter, which only contains a time-stamp, is a fairly crude way of detecting if the stored data has actually been changed. In particular, when the `getRawValue`-method is used, the `lastModified`-getter doesn't cope with data being modified from the "outside".
To fix these issues[1], and to prevent any future bugs in this code, this patch introduces a new `AnnotationStorage.hash`-getter which computes a hash of the currently stored data. To simplify things this re-uses the existing `MurmurHash3_64`-implementation, which required moving that file into the `src/shared/`-folder, since its performance should be good enough here.
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[1] Given how the `AnnotationStorage.lastModified`-getter was used, this would have been limited to *printing* of forms.
- since resetForm function reset a field value a calculateNow is consequently triggered.
But the calculate callback can itself call resetForm, hence an infinite recursive loop.
So basically, prevent calculeNow to be triggered by itself.
- in Firefox, the letters entered in some fields were duplicated: "AaBb" instead of "AB".
It was mainly because beforeInput was triggering a Keystroke which was itself triggering
an input value update and then the input event was triggered.
So in order to avoid that, beforeInput calls preventDefault and then it's up to the JS to
handle the event.
- fields have a property valueAsString which returns the value as a string. In the
implementation it was wrongly used to store the formatted value of a field (2€ when the user
entered 2). So this patch implements correctly valueAsString.
- non-rendered fields can be updated in using JS but when they're, they must take some properties
in the annotationStorage. It was implemented for field values, but it wasn't for
display, colors, ...
- it fixes#14862 and #14705.
Interestingly enough this appears to be the very first case of *encoded* dest-strings, in /GoTo destination dictionaries, that we've actually come across. What's really fascinating is that it's less than a week after issue 14847, given that these issues are *somewhat* similar.
As it turns out, most of the code-paths in the `PDFImage`-class won't actually pass the TypedArray (containing the image-data) to the `ColorSpace`-code. Hence we *generally* don't need to force the image-data to be a `Uint8ClampedArray`, and can just as well directly use a `Uint8Array` instead.
In the following cases we're returning the data without any `ColorSpace`-parsing, and the exact TypedArray used shouldn't matter:
- b72a448327/src/core/image.js (L714)
- b72a448327/src/core/image.js (L751)
In the following cases the image-data is only used *internally*, and again the exact TypedArray used shouldn't matter:
- b72a448327/src/core/image.js (L762) with the actual image-data being defined (as `Uint8ClampedArray`) further below
- b72a448327/src/core/image.js (L837)
*Please note:* This is tagged `api-minor` because it's API-observable, given that *some* image/mask-data will now be returned as `Uint8Array` rather than using `Uint8ClampedArray` unconditionally. However, that seems like a small price to pay to (slightly) reduce memory usage during image-conversion.
Initially I considered updating the `NameOrNumberTree`-implementation to handle encoded keys, however that quickly became somewhat messy (especially in the `NameOrNumberTree.get`-method) since only NameTrees using string-keys.
Hence the easiest solution, as far as I'm concerned, was thus to just update the `Catalog.destinations`-getter instead. Please note that in the referenced PDF document the `Catalog.destination`-method will thus fallback to fetch all destinations, which should be fine since this is the very first case of encoded keys that we've seen.
Also changes the `NameOrNumberTree.getAll`-method to prevent a possible run-time error, although we've so far not seen such a case, for any non-Array Kids-entries found in a NameTree/NumberTree.
Finally, to improve overall consistency and to hopefully prevent future bugs, the patch also updates a couple of other `NameTree` call-sites to correctly handle encoded keys. (Note that the `Catalog.attachments`-getter was already doing this.)
While working on PR 14825, I couldn't help noticing that the code to increment the `count` for cached ImageMasks was repeated multiple times. Hence it makes sense, as far as I'm concerned, to move this into a helper function instead.
Currently we only insert optionalContent-data into the operatorList the first time that an image is parsed, which will (in hindsight) obviously cause problems for cached images.
Hence we also need to insert the optionalContent-data in the various worker-thread image caches, such that it can be accessed in the fast-paths that are used to skip re-parsing of images.
In order to reduce the amount of repeated code, this patch also adds a new `OperatorList`-method that takes care of inserting the necessary data in the operatorList.
