While it's slightly difficult to trigger in practice, unless the `defaultZoomDelay`-value is increased, it's currently possible to generate thumbnails from *partially* rendered pages when doing *temporary* CSS-only zooming.
We shouldn't dispatch a "pagerendered"-event when doing *temporary* CSS-only zooming, but simply wait until the actual rendering is done.
While I don't believe that this regression has caused any actual bugs, dispatching *duplicate* events is nonetheless inconsistent and should be fixed.
This commit makes the following required changes:
- Replace custom cache trimming logic in favor of the (per our request)
newly added `trimCache` method in Puppeteer. Not only does this greatly
simplify our code and prevents having to import Puppeteer internals,
it's also necessary because Puppeteer 20 removed the `BrowserFetcher`
API in favor of the new separate `@puppeteer/browsers` package.
- Start browsers in series instead of in parallel. Parallel browser
starts broke since Puppetter 19.1.0 and it turns out that it has never
been supported officially, so it worked more-or-less by accident.
Starting browsers in series is the supported way, is almost equally
fast and ensures that we avoid any race conditions during startup.
Finally, it also allows us to remove the `browserPromise` state on our
session objects.
Fixes#15865.
This patch does two things:
- Moves the updating of thumbnails into `web/app.js`, via a new `PDFSidebar` callback-function, to avoid having to include otherwise unnecessary parameters when initializing a `PDFSidebar`-instance.
- Only attempt to generate thumbnail-images from pages that are *cached* in the viewer. Note that only pages that exist in the `PDFPageViewBuffer`-instance can be rendered, hence it's not actually meaningful to check every single page when updating the thumbnails.
For large documents, with thousands of pages, this should be a tiny bit more efficient when e.g. opening the sidebar since we no longer need to check pages that we know have not been rendered.
The way that the cleanup was implemented in PR 12613 has always bothered me slightly, since the `isPageCached`-method that I introduced there always felt quite out-of-place in the `IPDFLinkService`-implementations.
By introducing a new "thumbnailrendered" event, similar to the existing "pagerendered" one, we're able to move the cleanup handling into the `PDFViewer`-class instead.
The way that this was implemented in PR 10217 has always bothered me slightly, since the `isPageVisible`-method that I introduced there always felt quite out-of-place in the `IPDFLinkService`-implementations.
Hence this is instead replaced by a callback-function in `PDFFindController`, to handle the page-visibility checks. Note that since the `PDFViewer`-constructor always sets this callback-function, e.g. the viewer-component examples still work as-is.
Now that font-substitution has been implemented, we should be able to do much a better job at supporting non-embedded Wingdings fonts.
Given that this is a Windows-specific font, see https://en.wikipedia.org/wiki/Wingdings, this is however not guaranteed to work (well) on other platforms.
The affected font is non-embedded ZapfDingbats, however the PDF document for some inexplicable reason specifies the encoding as "WinAnsiEncoding" (which is obviously wrong).
To work-around this bug in the PDF generator, we'll simply ignore any explicitly specified named encoding for non-embedded symbol fonts.
- Remove the dependency on fit-curve;
- Improve the way to draw the current line in using a Path2D and
in clearing only the last part of the curve instead of clearing
all the canvas;
- Smooth the curve when drawing to avoid to have some changes after
the drawing ends;
- Make the smoothing a bit less agressive.
Given that inline images may contain "EI"-sequences in the image-data itself, actually finding the end-of-image operator isn't always straightforward.
Here we extend the implementation from PR 12028 to potentially check all of the following bytes, rather than stopping immediately. While we have fairly decent test-coverage for this code, whenever you're changing it there's unfortunately a slightly higher than normal risk of regressions. (You'd really wish that PDF generators just stop using inline images.)
