- 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.
With the changes in the previous patch, we can simplify the state-tracking by using the `PresentationModeState`-values directly in the `PDFPresentationMode` class.
We don't need to first check if the Dictionary contains the key, since trying to get a non-existent key simply returns `undefined` and we're already ensuring that the value is a boolean.
Furthermore, we shouldn't need to worry about the `Object.prototype` containing enumerable properties since the checks (in `src/core/worker.js`) done for `Array.prototype` *indirectly* also cover `Object`s. (Keep in mind that an `Array` is just a special kind of `Object` in JavaScript.)
The `pdfOpenParams` parameter has never really made sense in PresentationMode, since e.g. the zoom-value doesn't (generally) agree with the value chosen by the user prior to entering PresentationMode.
This has never mattered all that much, since the `viewBookmark`-button isn't visible in PresentationMode (nor is any other toolbar button for that matter). However, in the `PDFHistory`-implementation we're currently forced to handle this case specifically since we don't want to populate the browser history with nonsensical state.
Hence it makes overall sense, as far as I'm concerned, to tweak the "updateviewarea" event to include a *simplified* `pdfOpenParams` parameter when PresentationMode is active. Given that the `viewer components` don't include PresentationMode functionality, this change thus shouldn't matter for third-party users.
This method was originally added specifically to work-around bugs/issues related to PresentationMode in Google Chrome. Note that prior to PR 14112 we were using some CSS hacks to only show the current page in PresentationMode, and that could lead to the `getVisibleElements` function not always finding the correct elements.
However, after the changes in PR 14112 we're now using the Page-scrolling mode in PresentationMode and consequently there'll only be *a single* page visible at a time. Hence then `BaseViewer._getCurrentVisiblePage` helper method should no longer be needed, and when testing (locally) in Google Chrome everything seems to work correctly now.
The various functionality in `web/debugger.js` is currently *indirectly* added to the global scope, since that's how `var` works when it's used outside of any functions/closures.
Given how this functionality is being accessed/used, not just in the viewer but also in the API and textLayer, simply converting the entire file to a module isn't trivial[1]. However, we can at least export the `PDFBug`-part properly and then `import` that dynamically in the viewer.
Also, to improve the code a little bit, we're now *explicitly* exporting the necessary functionality globally.
According to MDN, see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/import#browser_compatibility, all the browsers that we now support have dynamic `imports` implementations.
---
[1] We could probably pass around references to the necessary functionality, but given how this is being used I'm just not sure it's worth the effort. Also, adding *official* support for these viewer-specific debugging tools in the API feels both unnecessary and unfortunate.
*Please note:* This is possibly bad/wrong in general, but I figured that submitting it for review wouldn't hurt.
It seems that even Adobe Reader doesn't handle the non-ASCII characters that appear in some of the fields correctly, however it should be pretty easy to improve things on the PDF.js side.
- it aims to fix#14685;
- add a basic object to get values from the parsed datasets;
- these annotations don't have an appearance so we must create one when printing or saving.
Please note that this patch is purposely quite basic, e.g. it doesn't add the polyfill-CSS in order to simplify the build process, and things such as `::backdrop` thus isn't working.
However, this patch does ensure that older browsers can at least still *access* all of the previous overlays and that things like e.g. opening of password-protected documents respectively printing still works.
This will hopefully improve the a11y a little bit in these dialogs, however there's most definately more things that can be done here (by someone more knowledgeable about a11y).
This way we're able to store the `<dialog>` elements directly, which removes the need to use manually specified name-strings thus simplifying both the `OverlayManager` itself and its calling code.
This replaces our *custom* overlays with standard `<dialog>` DOM elements, see https://developer.mozilla.org/en-US/docs/Web/HTML/Element/dialog, thus simplifying the related CSS, HTML, and JavaScript code.
With these changes, some of the functionality of the `OverlayManager` class is now handled natively (e.g. `Esc` to close the dialog). However, since we still need to be able to prevent dialogs from overlaying one another, it still makes sense to keep this functionality (as far as I'm concerned).
PDFScriptingManager uses the `mousedown` and `mouseup` listeners to keep
track of whether the mouse pointer is pressed in the `isDown` flag.
These listeners were registered to run during the bubbling phase of the
event dispatch, which can be interrupted if any of the previous event
listeners stopped the event propagation. An example of that is by
`GrabToPan` in web/grab_to_pan.js.
Since the mousedown (and mouseup) listeners of PDFScriptingManager are
free of side effects, and the intention is to always run them, it makes
most sense to register them with the capture flag.
- it aims to fix issue #14627;
- the basic idea of the recent text refactoring was to only consider the rendered visible whitespaces.
But sometimes, the heuristics aren't correct and although some whitespaces are in the text stream
they weren't in the text chunks because they were too small. Hence we added some exceptions, for example,
we always add a whitespace when it is between two non-whitespace chars but only when in the same Tj.
So basically, this patch removes the constraint to have the chars in the same Tj
(in using a circular buffer to save the two last chars) but don't add a space when the visible space is really
too small (hence `NOT_A_SPACE_FACTOR`).
Given that the textLayer-code has been using a `DocumentFragment` ever since PR 3356 (back in 2013), simply updating the type of the `container` property should be fine.
This patch also tries to, ever so slightly, improve the grammar of a couple of other properties in the typedef.
After the recent round of patches, I figured that we'd gone as far as possible in replacing `dir`-dependent CSS rules for the viewer.
However, it occurred that me that we could actually use a bit of CSS-trickery to get rid of the remaining ones. More specifically, this was done by defining a CSS variable whose value depends on the document direction and then using that variable together with `calc()` in the affected rules.
*Please note:* I suppose that this could perhaps be seen as a bit too "magical", hence I understand if this patch is ultimately rejected, however this is probably the only simple way to get rid of the remaining `dir`-dependent CSS rules.
