This was deprecated in PR 15758 and given that it's quite unlikely that any third-party users are relying on this functionality, since it was only ever added to support telemetry reporting in the Firefox PDF Viewer, it should hopefully be fine to remove this fairly quickly.
These changes reduce the bundle size of the Firefox PDF Viewer by 4.5 kB in total.
Currently both of the `AnnotationElement` and `KeyboardManager` classes contain *identical* `platform` getters, which seems like unnecessary duplication.
With the pre-processor we can also limit the feature-testing to only GENERIC builds, since `navigator` should always be available in browsers.
Given that this helper function is only used on the worker-thread, there's no reason to duplicate it in both of the `pdf.js` and `pdf.worker.js` files.
Given that this helper function is only used on the worker-thread, there's no reason to duplicate it in both of the `pdf.js` and `pdf.worker.js` files.
Given that these functions are virtually identical, with the latter only adding a BOM, we can combine the two. Furthermore, since both functions were only used on the worker-thread, there's no reason to duplicate this functionality in both of the `pdf.js` and `pdf.worker.js` files.
- For text fields
* when printing, we generate a fake font which contains some widths computed thanks to
an OffscreenCanvas and its method measureText.
In order to avoid to have to layout the glyphs ourselves, we just render all of them
in one call in the showText method in using the system sans-serif/monospace fonts.
* when saving, we continue to create the appearance streams if the fonts contain the char
but when a char is missing, we just set, in the AcroForm dict, the flag /NeedAppearances
to true and remove the appearance stream. This way, we let the different readers handle
the rendering of the strings.
- For FreeText annotations
* when printing, we use the same trick as for text fields.
* there is no need to save an appearance since Acrobat is able to infer one from the
Content entry.
These variables are left-over from the initial implementation, back when `String.prototype.padStart` didn't exist and we thus had to pad manually (using a loop).
Currently, during text-extraction, we're repeatedly normalizing and (when necessary) reversing the unicode-values every time. This seems a little unnecessary, since the result won't change, hence this patch moves that into the `Glyph`-instance and makes it *lazily* initialized.
Taking the `tracemonkey.pdf` document as an example: When extracting the text-content there's a total of 69236 characters but only 595 unique `Glyph`-instances, which mean a 99.1 percent cache hit-rate. Generally speaking, the longer a PDF document is the more beneficial this should be.
*Please note:* The old code is fast enough that it unfortunately seems difficult to measure a (clear) performance improvement with this patch, so I completely understand if it's deemed an unnecessary change.
All of the these constants have been deprecated for a while, and with the upcoming *major* version this seems like a good time to remove them.
For the string-constants we can simply remove them, but the number-constants are left commented out since we don't want to re-number the list to prevent third-party breakage.
This method was originally added in PR 1157 (back in 2012), however its only call-site was then removed in PR 2423 (also in 2012).
Hence this method has been completely unused for nearly a decade, and it should thus be safe to remove it.
Currently the compatibility-file is loaded using a standard `import`-statement and while its code is enclosed in a pre-processor block, and thus is excluded in e.g. the MOZCENTRAL build-target, it still results in the *built* `pdf.js`/`pdf.worker.js` files having an effectively empty closure as a result.
By moving the checks from `src/shared/compatibility.js` and into `src/shared/util.js` instead, we can load the file using a build-time `require`-statement and thus avoid that closure.
Note that with these changes the compatibility-file will no longer be loaded in development mode, i.e. when `gulp server` is used. However, this shouldn't be a big issue given that none of its included polyfills could be loaded then anyway (since `require`-statements are being used) and that it's really only intended for the `legacy`-builds of the library.
Fewer dependencies shouldn't be a bad idea in general, and given that the `node-canvas` package already include a `DOMMatrix` polyfill we can simply use that one instead.
This replaces the boolean `annotationEditorEnabled` option/preference with a "proper" `annotationEditorMode` one. This way it's not only possible for the user to control if Editing is enabled/disabled, but also which *specific* Editing-mode should become enabled upon PDF document load.
Given that Editing is not enabled/released yet, I cannot imagine that changing the name and type of the option/preference should be an issue.
*Please note:* The dates below are still a little ways off, however that obviously won't affect the existing PDF.js releases. Hence I think that we can make these changes now, since by the time of the *next* official PDF.js release they'll likely match up pretty well.[1]
While we "support" some (by now) fairly old browsers, that essentially means that the library (and viewer) will load and that the basic functionality will work as intended.[2]
However, in older browsers, some functionality may not be available and generally we'll ask users to update to a modern browser when bugs (specific to old browsers) are reported.[3]
Since we've previously settled on only supporting browsers/environments that are approximately *three years old*, this patch updates the minimum supported browsers/environments as follows:
- Chrome 76, which was released on 2019-07-30; see https://en.wikipedia.org/wiki/Google_Chrome_version_history
- Firefox ESR (as before); see https://wiki.mozilla.org/Release_Management/Calendar
- Safari 13, which was released on 2019-09-19; see https://en.wikipedia.org/wiki/Safari_version_history#Safari_13
- Node.js 14, which was release on 2020-04-21 (all older versions have reached EOL); see https://en.wikipedia.org/wiki/Node.js#Releases
---
[1] Given that the releases usually happen every two to three months.
[2] Assuming that a `legacy/`-build is being used, of course.
[3] In general it's never a good idea to use old/outdated browsers, since those may contain *known* security vulnerabilities.
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.
- Approximate the drawn curve by a set of Bezier curves in using
js code from https://github.com/soswow/fit-curves.
The code has been slightly modified in order to make the linter
happy.
- Ensure that the modified-warning won't be displayed, when navigating away from the viewer, if the user has added custom Annotations and then *removed all* of them.
- Ensure that the *initial* editor-buttons state, i.e. the `toggled`-class, is correctly displayed in the toolbar when then viewer loads.
- Tweak the CSS-classes for the editor-buttons, such that they use the correct focus/hover-rules (similar to the sidebar-buttons).
- Remove a no longer accurate comment from the `BaseViewer.annotationEditorMode`-setter.
- Address a couple of *smaller* outstanding review comments, including some re-formatting changes, from PR 14976.
- 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.
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.
---
[1] Given how the `AnnotationStorage.lastModified`-getter was used, this would have been limited to *printing* of forms.
- most of the time the current transform is a scaling one (modulo translation),
hence it's possible to avoid to apply the transform on each bbox and then apply
it a posteriori;
- compute the bbox when it's possible in the worker.
- avoid to call normalizeRect which clones the rectangles: it's useless
and time consuming;
- in profiling the pdf in bug 1135277, the time spent in intersect drops
from ~1s to ~30ms.
- write some uint32 instead of uint8 to avoid the check before clamping;
- unroll the loop to write data in the buffer
- but keep a loop for the last element of a line: it likely doesn't hurt
that much since it's executed only for one time for each line;
- I tested on a macbook with an Apple chip, and on Firefox nightly the new
code is almost 3.5x faster than before (~1.8x with Chrome).
- it aims to partially fix performance issue reported: https://bugzilla.mozilla.org/show_bug.cgi?id=857031;
- the idea is too avoid to use byte arrays but use ImageBitmap which are a way faster to draw:
* an ImageBitmap is Transferable which means that it can be built in the worker instead of in the main thread:
- this is achieved in using an OffscreenCanvas when it's available, there is a bug to enable them
for pdf.js: https://bugzilla.mozilla.org/show_bug.cgi?id=1763330;
- or in using createImageBitmap: in Firefox a task is sent to the main thread to build the bitmap so
it's slightly slower than using an OffscreenCanvas.
* it's transfered from the worker to the main thread by "reference";
* the byte buffers used to create the image data have a very short lifetime and ergo the memory used is globally
less than before.
- Use the localImageCache for the mask;
- Fix the pdf issue4436r.pdf: it was expected to have a binary stream for the image;
- Move the singlePixel trick from operator_list to image: this way we can use this trick even if it isn't in a set
as defined in operator_list.
This function is currently placed in the `src/shared/util.js` file, which means that the code is duplicated in both of the *built* `pdf.js` and `pdf.worker.js` files. Furthermore, it only has a single call-site which is also specific to the `GENERIC`-build of the PDF.js library.
Hence this helper function is instead moved into the `src/display/api.js` file, in such a way that it's conditionally defined but still can be unit-tested.
According to the MDN compatibility data, see https://developer.mozilla.org/en-US/docs/Web/API/DOMMatrix/DOMMatrix#browser_compatibility, all browsers that we support have native `DOMMatrix` implementations (since quite some time too).
Hence Node.js is the only environment that lack `DOMMatrix` support, which probably isn't that surprising given that it's browser functionality.
While the `DOMMatrix` polyfill isn't that large, it nonetheless seems completely unnecessary to bundle it in the `legacy` builds when it's not needed in browsers. However, we can avoid that by simply listing `dommatrix` as a dependency for the `pdfjs-dist` library.
The call-sites are replaced by direct `typeof`-checks instead, which removes unnecessary function calls. Note that in the `src/`-folder we already had more `typeof`-cases than `isString`-calls.
All call-sites that use `wrapReason` should be passing a (possibly cloned) `Error` to the helper function, hence we shouldn't need to have a fallback code-path for any other data.
Note that for the `cancel`/`error` methods on Streams, since PR 11115 we've been asserting that the argument is in fact an `Error` as intended.
When calling `wrapReason` from *rejected* Promises, we should also be guaranteed that an `Error` is provided thanks to the ESLint rules `no-throw-literal` and `prefer-promise-reject-errors`.
The call-sites are replaced by direct `typeof`-checks instead, which removes unnecessary function calls. Note that in the `src/`-folder we already had more `typeof`-cases than `isNum`-calls.
These changes were *mostly* done using regular expression search-and-replace, with two exceptions:
- In `Font._charToGlyph` we no longer unconditionally update the `width`, since that seems completely unnecessary.
- In `PDFDocument.documentInfo`, when parsing custom entries, we now do the `typeof`-check once.
According to the MDN compatibility data, see https://developer.mozilla.org/en-US/docs/Web/API/ReadableStream#browser_compatibility, all browsers that we support have native `ReadableStream` implementations (since quite some time too).
Hence only Node.js is now lagging behind w.r.t. `ReadableStream` support, and its experimental implementation doesn't really help us given the life-span of the LTS releases (see https://en.wikipedia.org/wiki/Node.js#Releases).
It seems quite unfortunate to bundle a `ReadableStream` polyfill in the `legacy` builds when it's unnecessary in browsers, given its overall size, but fortunately we can avoid that by simply listing `web-streams-polyfill` as a dependency for the `pdfjs-dist` library.
With recent changes, specifically PR 14515 *and* the previous patch, the `createObjectURL` helper function is now only used with the SVG back-end.
All other call-sites, throughout the code-base, are now using `URL.createObjectURL(...)` directly and it no longer seems necessary to keep exposing the helper function in the API.
Finally, the `createObjectURL` helper function is moved into the `src/display/svg.js` file to avoid unnecessarily duplicating this code on both the main- and worker-threads.
Please note that while we "support" some (by now) fairly old browsers, that essentially means that the library (and viewer) will load and that the basic functionality will work as intended.[1]
However, in older browsers, some functionality may not be available and generally we'll ask users to update to a modern browser when bugs (specific to old browsers) are reported.[2]
There's always a question of just how old browsers the PDF.js contributors can realistically support, and here I'm suggesting that we place the cut-off point at approximately *three* years.
With that in mind, this patch updates the *minimum* supported browsers (and environments) as follows:
- Chrome 73, which was released on 2019-03-12; see https://en.wikipedia.org/wiki/Google_Chrome_version_history
- Firefox ESR (as before); see https://wiki.mozilla.org/Release_Management/Calendar
- Safari 12.1, which was released on 2019-03-25; see https://en.wikipedia.org/wiki/Safari_version_history#Safari_12
- Node.js 12, which was release on 2019-04-23 (and will soon reach EOL); see https://en.wikipedia.org/wiki/Node.js#Releases
---
[1] Assuming a `legacy`-build is being used, of course.
[2] In general it's never a good idea to use an old/outdated browser, since those may contain *known* security vulnerabilities.
This allows us to remove the manually implemented `structuredClone` polyfill, thus reducing the maintenance burden for the `LoopbackPort` class; refer to https://github.com/zloirock/core-js#structuredclone
*Please note:* While `structuredClone` support landed already in Firefox 94, Google Chrome only added it in version 98 (currently in Beta). However, given that the `LoopbackPort` will only be used together with *fake workers* in browsers this shouldn't be too much of a problem.[1]
For Node.js environments, where *fake workers* are unfortunately necessary, using a `legacy/`-build is already required which thus guarantees that the `structuredClone` polyfill is available.
Also, the patch updates core-js to the latest version since that one includes `structuredClone` improvements; please see https://github.com/zloirock/core-js/releases/tag/v3.20.3
---
[1] Given that we only support browsers with proper worker support, if *fake workers* are being used that essentially indicates a configuration problem/error.
