Currently we have a `Util`-helper for computing the bounding-box of a Bézier curve, however for simple points and rectangles we repeat virtually identical code in many spots throughout the code-base.
- Introduce new `Util.pointBoundingBox` and `Util.rectBoundingBox` helpers.
- Remove the "fallback" from `Util.bezierBoundingBox` and only support passing in a `minMax`-array, since there's only a single call-site using the other format and it could be easily updated.
With this patch, all the paths components are collected in the worker until a path
operation is met (i.e., stroke, fill, ...).
Then in the canvas a Path2D is created and will replace the path data transfered from the worker,
this way when rescaling, the Path2D can be reused.
In term of performances, using Path2D is very slightly improving speed when scaling the canvas.
This is an admittedly very basic polyfill, to allow us to remove a bunch of inline feature testing, that I've thrown together based on reading https://developer.mozilla.org/en-US/docs/Web/API/AbortSignal/any_static and related MDN articles.
Compared to PR 19218 it's obviously much more "primitive", however the implementation is simple and it doesn't suffer from any licensing issues (since I wrote the code myself).
Currently we have a number of spots in the code-base where we need to clamp a value to a [min, max] range. This is either implemented using `Math.min`/`Math.max` or with a local helper function, which leads to some unnecessary duplication.
Hence this patch adds and re-uses a single helper function for this, which we'll hopefully be able to remove in the future once https://github.com/tc39/proposal-math-clamp/ becomes generally available.
Currently we re-implement the same helper function twice, which in hindsight seems like the wrong decision since that way it's quite easy for the implementations to accidentally diverge.
The reason for doing it this way was because the code in the worker-thread is able to check for `Ref`- and `Name`-instances directly, which obviously isn't possible in the viewer but can be solved by passing validation-functions to the helper.
This patch is adding some code in order to extract a drawing as curves from an image.
The algorithm is basically the following:
- reduce the dimensions
- make it gray
- apply a bilateral filter in order to add some blurryness while keeping the edges
- compute the histogram
- guess what's the background color which should contain a large majority of the pixels
- make a binary image
- extract the contours in using the Suzuki algorithm
- apply the Douglas-Peucker algorithm in order to reduce the number of points
The algorithm is improvable but it should work pretty well if there's a clear difference between
the background and the drawing.
In a v2 we could use a ML model in order to improve the extraction.
There's few changes related to the UI in order to make the tool usable, but they're very basic
for the moment.
After PR 2317, which landed in 2012, we'd immediately clean-up after rendering for pages with large image resources. This had the effect that re-rendering, e.g. after zooming, would force us to re-parse the entire page which could easily lead to bad performance.
In PR 16108, which landed in 2023, we tried to lessen the impact of that by slightly delaying clean-up however that's obviously not a perfect solution (and it increased the complexity of the relevant code).
Furthermore, the condition for this "immediate" clean-up seems a bit arbitrary to me since a page could easily contain a large number of smaller images whose total size vastly exceeds the threshold.
Hence this patch, which suggests that we remove the conditional and delayed clean-up after rendering. Compared to the situation back in 2012, a number of things have improved since:
- We have *multiple* caches for repeated image-resources on the worker-thread[1], which helps reduce overall memory usage and improves performance.
- We downsize huge images on the worker-thread, which means that the images we're using on the main-thread cannot be arbitrarily large.
- The amount of available RAM on devices should be a lot higher, since more than a decade has passed.
A future improvement here, for more resource constrained environments, could be to instead clean-up when actually needed using e.g. `WeakRef`s (see issue 18148).
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[1] More specifically:
- `LocalImageCache`, which caches image-data by /Name and /Ref on the `PartialEvaluator.prototype.getOperatorList` level.
- `RegionalImageCache`, which caches image-data by /Ref on the `PartialEvaluator`-instance (i.e. at the page) level.
- `GlobalImageCache`, which caches image-data by /Ref globally at the document level.
These old exceptions have a fair amount of overlap given how/where they are being used, which is likely because they were introduced at different points in time, hence we can shorten and simplify the code by replacing them with a more general `ResponseException` instead.
Besides an error message, the new `ResponseException` instances also include:
- A numeric `status` field containing the server response status, similar to the old `UnexpectedResponseException`.
- A boolean `missing` field, to allow easily detecting the situations where `MissingPDFException` was previously thrown.
This patch makes a clear separation between the way to draw and the editing stuff.
It adds a class DrawEditor which should be extended in order to create new drawing tools.
As an example, the ink tool has been rewritten in order to use it.
We can remove most feature testing from this helper function, with the exception of `randomUUID` since that's only available in "secure contexts", and also remove the fallback code-path.
Note that this code was only added for Node.js compatibility, and it's no longer necessary now that the minimum support version is `20`; see also https://developer.mozilla.org/en-US/docs/Web/API/Crypto#browser_compatibility
Finally, this patch also adds a basic unit-test for the helper function.
The purpose of these changes is to make it more difficult to accidentally include logging statements, used during development and debugging, when submitting patches for review.
For (almost) all code residing in the `src/` folder we should use our existing helper functions to ensure that all logging can be controlled via the `verbosity` API-option.
For the `test/unit/` respectively `test/integration/` folders we shouldn't need any "normal" logging, but it should be OK to print the *occasional* warning/error message.
Please find additional details about the ESLint rule at https://eslint.org/docs/latest/rules/no-console
This allows end-users to forcibly disable `ImageDecoder` usage, even if the browser appears to support it (similar to the pre-existing option for `OffscreenCanvas`).
This allows using the new methods in browsers that support them, e.g. Firefox 133+, while still providing fallbacks where necessary; see https://github.com/tc39/proposal-arraybuffer-base64
*Please note:* These are not actual polyfills, but only implements what we need in the PDF.js code-base. Eventually this patch should be reverted, once support is generally available.
After the binary CMap format had been added there were also some ideas about *maybe* providing other formats, see [here](https://github.com/mozilla/pdf.js/pull/8064#issuecomment-279730182), however that was over seven years ago and we still only use binary CMaps.
Hence it now seems reasonable to simplify the relevant code by removing `CMapCompressionType` and instead just use a boolean to indicate the type of the built-in CMaps.
A recent change in Firefox induced too much difference between the text widths computed in using a Canvas
and the ones computed by the text layout engine when rendering the text layer. Consequently, the
text selection can be bad on Windows with some fonts like Arial or Consolas.
This patch is a workaround to try to use in first place some fonts which don't have the problem.
We have a number of base-classes that are only intended to be extended, but never to be used directly. To help enforce this during development these base-class constructors will check for direct usage, however that code is obviously not needed in the actual builds.
*Note:* This patch reduces the size of the `gulp mozcentral` output by `~2.7` kilo-bytes, which isn't a lot but still cannot hurt.
In *hindsight* this seems like a better idea, since it avoids the need to manually pass `isEditing` around as a boolean value.
Note that `RenderingIntentFlag` is *internal* functionality, not exposed in the official API, which means that it can be extended and modified as necessary.
This replaces our custom `PromiseCapability`-class with the new native `Promise.withResolvers()` functionality, which does *almost* the same thing[1]; please see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/withResolvers
The only difference is that `PromiseCapability` also had a `settled`-getter, which was however not widely used and the call-sites can either be removed or re-factored to avoid it. In particular:
- In `src/display/api.js` we can tweak the `PDFObjects`-class to use a "special" initial data-value and just compare against that, in order to replace the `settled`-state.
- In `web/app.js` we change the only case to manually track the `settled`-state, which should hopefully be OK given how this is being used.
- In `web/pdf_outline_viewer.js` we can remove the `settled`-checks, since the code should work just fine without it. The only thing that could potentially happen is that we try to `resolve` a Promise multiple times, which is however *not* a problem since the value of a Promise cannot be changed once fulfilled or rejected.
- In `web/pdf_viewer.js` we can remove the `settled`-checks, since the code should work fine without them:
- For the `_onePageRenderedCapability` case the `settled`-check is used in a `EventBus`-listener which is *removed* on its first (valid) invocation.
- For the `_pagesCapability` case the `settled`-check is used in a print-related helper that works just fine with "only" the other checks.
- In `test/unit/api_spec.js` we can change the few relevant cases to manually track the `settled`-state, since this is both simple and *test-only* code.
---
[1] In browsers/environments that lack native support, note [the compatibility data](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/withResolvers#browser_compatibility), it'll be polyfilled via the `core-js` library (but only in `legacy` builds).
*Please note:* This is a micro optimization, hence I fully understand if the patch is rejected.
Currently we create two temporary Arrays and have to iterate twice in total when building the final `hexNumbers` Array.
With this patch there's only one temporary Array and a single iteration required to build the final `hexNumbers` Array.
It isn't really a fix for the mentioned bug but it slightly improve things.
In reducing the memory use, the time spent in the GC is reduced either.
The algorithm to compute the bounding box is the same as before but it has just
been rewritten to be more efficient.
This manually ignores some cases where the resulting auto-formatting would not, as far as I'm concerned, constitute a readability improvement or where we'd just end up with more overall indentation.
Please see https://eslint.org/docs/latest/rules/arrow-body-style
The doorhanger for highlighting has a basic color picker composed of 5 predefined colors
to set the default color to use.
These colors can be changed thanks to a preference for now but it's something which could
be changed in the Firefox settings in the future.
Each highlight has in its own toolbar a color picker to just change its color.
The different color pickers are so similar (modulo few differences in their styles) that
this patch introduces a new class ColorPicker which provides a color picker component
which could be reused in future editors.
All in all, a large part of this patch is dedicated to color picker itself and its style
and the rest is almost a matter of wiring the component.
There are environments that include *incomplete* polyfills for the `navigator`-object, which may thus cause the PDF.js library to break.
Despite that clearly not being our fault, it may still result in bug reports filed against the PDF.js project; see e.g. 15728.
Currently this even seem to affect *the latest* version of Node.js; see e.g. [here].
*Please note:* Thanks to the pre-processor none of these changes affect the Firefox PDF Viewer, however it does add "overhead" when working with and reviewing the affected code (which is why I'm not crazy about this).
Currently the `WidgetAnnotationElement._getKeyModifier` method will always be falsy on Linux, which seems like a simple oversight. Looking at all the other `FeatureTest.platform` accesses we only handle the `isMac`-case specially, and it seems reasonable to do the same thing here.
The reason that this hasn't led to any bug reports is most likely that the `modifier`-property seems completely unused in the scripting-implementation.
Finally, with these changes we can (slightly) simplify the `FeatureTest.platform` implementation.
The main stamp button will be used to just enter in a add/edit image mode:
- the user can add a new image in using the new button.
- the user can edit an image in resizing, moving it.
In image mode, when the user clicks outside on the page but not on an editor,
then all the selected editors will be unselected.
Selected editors can be moved in using the arrows:
- up/down/left/right will move the editors of 1 in page unit;
- ctrl (or meta)+up/down/left/right will move them of 10 in page unit.
- it'll improve the way to resize images: diagonally (in keeping ratio between dimensions)
or horizontally/vertically.
- the resizer was almost invisible in HCM.
- make a resize undoable/redoable.
With the changes in the previous patch the `isNodeJS`-helper no longer needs to live in its own file, which helps get rid of a closure in the *built* files.
In the last couple of years we've been quicker to remove support for older browsers/environments, which means that at this point in time we don't bundle that many polyfills. (The polyfills are also generally simpler nowadays, ever since we removed support for e.g. Internet Explorer.)
Rather than having to *manually* handle the polyfills, we can actually let Babel take care of bundling the necessary polyfills for us; please refer to https://babeljs.io/docs/babel-preset-env
The only exception here is the Node.js-specific compatibility-code, which is moved into the `src/display/node_utils.js` file. This ought to be fine since workers are not available/used in Node.js-environments.
*Please note:* For the `legacy`-builds this will increase the size of the *built* files, however that seems like a very small price to pay in order to simplify maintenance of the general PDF.js library.
