In the mac case we don't want to care about the scaleFactor threshold
because else if too big another move could start and then subsequent
events aren't considered as wheel events.
It isn't really ideal and at some point we'll need to find a way at
least for the Firefox case to get the real events instead of the fake
wheel ones.
In looking at a profile, I noticed in Marker chart that there's an animation
for loading-icon.gif even if this icon isn't visible.
This patch doesn't completely remove it but just slightly postpones it.
This further extends the web-specific import maps introduced in PR 16009, to allow removing *most* of the build-time `require` statements from the viewer. The few remaining ones are fallbacks used for the COMPONENTS respectively the `legacy` GENERIC builds.
After the compatibility updates in PR 15968 it's no longer strictly necessary to build the `viewer.css` file in order for the *development viewer* to work in Chromium-based browsers.
*Please note:* Given that Chromium-based browsers still don't support the *unprefixed* `mask-image` property the icons won't look right, however the development viewer itself works.
Given that Firefox is the *primary* development target, and that running `gulp generic` locally will generate polyfilled CSS, it seems reasonable to make this simplification here.
Currently there's no toolbar in the GV-viewer, hence invoking the pageLabels functionality isn't meaningful and just leads to unnecessary parsing on both the main- and worker-threads. (And if a toolbar is added at some point, it's not clear to me if we'd want to support pageLabels in the GV-viewer anyway.)
Currently we have a couple of pre-processor checks, specifically for the GV-viewer, spread throughout the code. This works fine when *building* the viewer, however they're obviously ignored in development mode (i.e. `gulp server`).
This leads to a situation where the GV development viewer, i.e. http://localhost:8888/web/viewer-geckoview.html, behaves subtly different from its built version. This could easily lead to bugs, hence this patch introduces a development mode constant to hopefully improve things here.
Finally, in a follow-up to PR 15842, also ignores the `pageMode`-state since there's no sidebar available.
Currently there's no UI for this functionality in the GV-viewer, however we still call the API methods. This potentially leads to a bunch of worker-thread parsing, for PDF documents with these features, despite the result being completely unused.
Given that mobile devices are usually more resource constrained than desktop/laptop computers, not to mentioned battery life, we can avoid doing work that'll just be ignored anyway.
Given that the GV-viewer isn't using most of the UI-related components of the default-viewer, we can avoid including them in the *built* viewer to save space.[1]
The least "invasive" way of implementing this, at least that I could come up with, is to leverage import maps with suitable stubs for the GV-viewer.
The one slightly annoying thing is that we now have larger import maps across multiple html-files, and you'll need to remember to update all of them when making future changes.
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[1] With this patch, the built `viewer.js` size is 391 kB and `viewer-geckoview.js` is 285 kB.
By default we're using worker-thread fetching (in browsers) of this data nowadays, however in Node.js environments or if the user provides custom factories we still fallback to main-thread fetching.
Hence it makes sense, as far as I'm concerned, to move this initialization into the `getDocument` function to ensure that the factories can actually be initialized *before* attempting to load the document.
Also, this further reduces the amount of `getDocument` parameters that we need to pass into into the `WorkerTransport` class.
Currently we're passing all available parameters to this function respectively class, despite that not actually being necessary.
By splitting the parameters we not only improve the structure, and basically "document" the code a little bit, but we can also simplify the `_fetchDocument` function considerably.
This is very old code, where we loop through the user-provided options and build an internal parameter object. To prevent errors we also need to ensure that the parameters are correct/valid, which is especially important for the ones that are sent to the worker-thread such that structured cloning won't fail.[1]
Over the years this has led to more and more code being added in `getDocument` to validate the user-provided options, and at this point *most* of them have at least basic validation. However the way that this is implemented feels slightly backwards, since we first build the internal parameter object and only *afterwards* validate those parameters.[2]
Hence this patch changes the `getDocument` function to instead check/validate the supported options upfront, and then *explicitly* build the internal parameter object with only the needed properties.
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[1] Note the supported types at https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API/Structured_clone_algorithm#supported_types
[2] The internal parameter object may also, because of the loop, end up with lots of unnecessary properties since anything that the user provides is being copied.
These functions invoke the `PDFViewer.currentPageNumber` setter, which already checks that a `pdfDocument` is currently active. Also, given that they're event handlers for the First/Last-page buttons (in the SecondaryToolbar) they can't be invoked before the viewer has been fully initalized.
The default value of the `--scale-select-width` CSS variable has been choosen such that it should be large enough for most locales. This means that in many locales we don't even update the CSS variable at all, and for those locales where we do the update happens *one time* early during the viewer initialization (i.e. before the PDF document has loaded).
*Please note:* Compared to other recent PRs, the effect of these changes ought to be really tiny and are mostly done to promote better coding patterns.
We should be able to let Jasmine simply compare directly against an actually empty Object, rather than using a manually implemented helper function for that.
A number of methods have their Promises cached, to avoid repeated worker round-trips, since they're expected to be called more than once from the default viewer. The way that the caching is currently implemented means that we need to remember to manually clear these Promises on document cleanup/destruction, and it'd be nice to avoid that.
With this patch the relevant Promises are now instead placed in just one `Map`, which is easy to clear, and a new helper method is also introduced to reduce duplication for *simple* `WorkerTransport` methods.
The reasons for making this change are:
- There's no UI available to toggle the cursor-tools in the GeckoView-specific viewer.
- The `HandTool`-implementation basically *simulates* touch scrolling, and is thus unlikely to be helpful/useful anyway.
- PR 15831 already changed the relevant call-sites to handle `PDFViewerApplication.pdfCursorTools` being undefined.
Some of the code in this method is *very* old, and we could thus modernize it a little bit by removing a couple of the loops used to build the `getDocument` argument.
These `@media` rules were most likely just copy-pasted from the regular viewer, however none of them are currently necessary since the GeckoView-specific viewer doesn't have any toolbars.
Note that the whole purpose of these CSS rules are to make the toolbar, of the regular viewer, responsive. If we in the future add toolbars for the GeckoView-specific viewer, these rules most likely wouldn't be usable as-is anyway.
This option was added specifically for third-party users, but has never been used in the PDF.js project itself. Furthermore there's no preference that can be used to enable it, and you need to provide the `removePageBorders` option when initializing a `PDFViewer`-instance.
This patch thus get rid of a little bit more unused code in the Firefox PDF Viewer.
*Unfortunately I missed this during testing/reviewing of PR 15992.*
With the changes in PR 15992 we're now only adding the `loadingIcon`-class when rendering is actually `RUNNING`, in order to improve overall performance.
However when resetting the page, i.e. the `INITIAL` state, we also need to remove the `loadingIcon` completely. Without this patch if you scroll through a document where the pages don't load instantaneously, see e.g. issue 2504, we'll leave the `loadingIcon`-class attached to pages that have had their rendering cancelled *and* also been evicted from the `PDFPageViewBuffer`-instance.
