It has few cool features:
- all the canvas used during the rendering can be viewed;
- the different properties in the graphics state can be viewed;
- the different paths can be viewed.
The purpose of PR 11844 was to reduce memory usage once fonts have been attached to the DOM, since the font-data can be quite large in many cases.
Unfortunately the new `clearData` method added in PR 20197 doesn't actually remove *anything*, it just replaces the font-data with zeros which doesn't help when the underlying `ArrayBuffer` itself isn't modified.
The method does include a commented-out `resize` call[1], but uncommenting that just breaks rendering completely.
To address this regression, without having to make large or possibly complex changes, this patch simply changes the `clearData` method to replace the internal buffer/view with its contents *before* the font-data.
While this does lead to a data copy, the size of this data is usually orders of magnitude smaller than the font-data that we're removing.
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[1] Slightly off-topic, but I don't think that patches should include commented-out code since there's a very real risk that those things never get found/fixed.
At the very least such cases should be clearly marked with `// TODO: ...` comments, and should possibly also have an issue filed about fixing the TODO.
The `PagesMapper` class currently makes up one third of the `src/display/display_utils.js` file size, and since its introduction it's grown (a fair bit) in size.
Note that the intention with files such as `src/display/display_utils.js` was to have somewhere to place functionality too small/simple to deserve its own file.
- Mention the internal viewer in the README, such that it's easier to find.
- Implement a new `INTERNAL_VIEWER` define, such that it's easier to limit code to only the "internal-viewer" gulp target.
- Only include the "GetRawData" message-handler when needed. Note that the `MessageHandler` [already throws](eb159abd6a/src/shared/message_handler.js (L121-L123)) for any missing handler.
- Move the various new helper functions from `src/core/document.js` and into their own file. The reasons for doing this are:
- That file is already quite large and complex as-is, and these helper functions are slightly orthogonal to its main functionality.
- Babel isn't able to remove all of the new code, and by moving this into a separate file we can guarantee that no extra code ends up in e.g. Firefox.
When recording bboxes for images, it's enough to record their
clip box / bounding box without needing to run the full bbox
tracking of the image's dependencies.
This patch adds right-click support for images in the PDF, allowing
users to download them. To minimize memory consumption, we:
- Do not store the images separately, and instead crop them out of the
PDF page canvas
- Only extract the images when needed (i.e. when the user right-clicks
on them), rather than eagery having all of them available.
To do so, we layer one empty 0x0 canvas per image, stretched to cover
the whole image, and only populate its contents on right click.
These images need to be inside the text layer: they cannot be _behind_
it, otherwise they would be covered by the text layer's container and
not be clickable, and they cannot be in front of it, otherwise they
would make the text spans unselectable.
This feature is managed by a new preference, `imagesRightClickMinSize`:
- when it's set to `-1`, right-click support is disabled
- when set to `0`, all images are available for right click
- when set to a positive integer, only images whose width and height are
greater than or equal to that value (in the PDF page frame of
reference) are available for right click.
This features is disabled by default outside of MOZCENTRAL, as it
significantly degrades the text selection experience in non-Firefox
browsers.
In PR 19548 these checks were added to ensure that the font-data sent from the worker-thread *always* include correct `disableFontFace` and `fontExtraProperties` data.
For some reason PR 20197 then changed the code such that these checks became effectively pointless, since these properties are now checked after the fact *and* the new getters provide fallback values.
This method is only used with loops, and it should be a tiny bit more efficient to use an iterator directly rather than first iterating through the underlying data to create a temporary `Array` that we finally iterate through at the call-site.
*Please note:* As port of these changes the chars/glyph caches, on the `Font` instances, are changed to use `Map`s rather than Objects.
This method is only used with loops, and it should be a tiny bit more efficient to use an iterator directly rather than first iterating through the underlying `Map` to create a temporary `Array` that we finally iterate through at the call-site.
The one from pdf.js.utils is a bit too old: a lot of bugs have been fixed
in the code that parses PDF files since then.
It's just an internal development tool, so it doesn't need to be perfect,
but it should be good enough to be useful.
A number of these unit-tests didn't actually cover the intended code-paths, since many of them *accidentally* matched the "file size is smaller than two range requests"-check.
The patch also updates `validateRangeRequestCapabilities` to use return-value names that are consistent with the class fields used in the various stream implementations.
Falling back to use the `loaded` byteLength if the server `contentLength` is unknown doesn't make a lot of sense, since it'd lead to the `onProgress` callback reporting `percent === 100` repeatedly while the document is loading despite that being obviously wrong.
Instead we'll now report `percent === NaN` in that case, thus showing the indeterminate progressBar, which seems more correct if the `contentLength` is unknown.
Please note that this code-path is normally not even reached, since streaming is enabled by default (applies e.g. to the Firefox PDF Viewer).
With these changes `0`, `NaN`, `null`, and `undefined` in the `total`-property all result in `percent === NaN` being reported by the callback, since previously e.g. `0` would result in `percent === 100` being reported unconditionally which doesn't make a lot of sense.
Also, remove the "indeterminate" loadingBar (in the viewer) if the `PDFDocumentLoadingTask` fails since there won't be any more data arriving and displaying the animation thus seems wrong.
This adds a basic non-MOZCENTRAL polyfill for now, which we should be able to remove once the next QuickJS version is released; note the pending changelog at f1139494d1/Changelog (L7)
This adds a *very basic* non-MOZCENTRAL polyfill for now, which we should be able to remove once the next QuickJS version is released; note the pending changelog at f1139494d1/Changelog (L8)
This is not only shorter, but (in my opinion) it also simplifies the code.
*Note:* In order to keep the *five* different `BasePDFStreamReader` implementations consistent, we purposely don't re-factor the `PDFWorkerStreamReader` class to support `for await...of` iteration.
Looking at the `BinaryCMapStream` implementation, it's basically a "regular" `Stream` but with added functionality for reading compressed CMap data.
Hence, by letting `BinaryCMapStream` extend `Stream`, we can remove an effectively duplicate method and simplify/shorten the code a tiny bit.
Currently the `customNames` are read one byte at a time, in a loop, and at every iteration converted to a string.
This can be replaced with the `BaseStream.prototype.getString` method, which didn't exist back when this function was written.
This method is usually used with loops, and it should be a tiny bit more efficient to use an iterator directly rather than first iterating through ` Map`-values to create a temporary `Array` that we finally iterate through at the call-site.
Note that the `getRawValues` method is old code, and originally the `Dict` class stored its data in a regular `Object`, hence why the old code was written that way.
This method is usually used with loops, and it should be a tiny bit more efficient to use an iterator directly rather than first iterating through ` Map`-keys to create a temporary `Array` that we finally iterate through at the call-site.
Note that the `getKeys` method is old code, and originally the `Dict` class stored its data in a regular `Object`, hence why the old code was written that way.
This changes a number of loops currently using `Dict.prototype.{getKeys, getRaw}`, since it should be a tiny bit more efficient to use an iterator directly rather than first iterating through `Map`-keys to create a temporary `Array` that we finally iterate through at the call-site.
Note that the `getKeys` method is much older than `getRawEntries`, and originally the `Dict` class stored its data in a regular `Object`, hence why the old code was written that way.
