The default viewer, and thus Firefox, depends on the `RenderTask.onContinue` functionality to pause/continue rendering (such that the most visible page always renders first).
Despite this functionality thus being very important, it has however never actually been tested *at all* as far as I can tell. Hence this patch which adds a new boolean `renderTaskOnContinue` parameter (`false` by default), that can be used to force a reference-test to use the `RenderTask.onContinue` code-path in the `InternalRenderTask` class.
Note that I purposely made this new reference-test behaviour *optional*, since I didn't want to negatively affect the general runtime of the tests (given that there's a slight delay added to the rendering). Also, for e.g. benchmarking you'd most likely want to stay away from the `RenderTask.onContinue` functionality for similar reasons.
This should reduce the possibility of accidentally truncating some inline images, while *not* causing the "EI" detection to become significantly slower.[1]
There's obviously a possibility that these added checks are not sufficient to catch *every* single case of "EI" sequences within the actual inline image data, but without specific test-cases I decided against over-engineering the solution here.
*Please note:* The interpolation issues are somewhat orthogonal to the main issue here, which is the truncated image, and it's already tracked elsewhere.
---
[1] I've looked at the issue a few times, and this is the first approach that I was able to come up with that didn't cause *unacceptable* performance regressions in e.g. issue 2618.
Versions of `needle` prior to `2.5.0` cannot cope with redirects (as documented: https://github.com/tomas/needle/issues/312).
This prevents prebuilt `canvas` binaries from being downloaded on MacOS,
requiring the global install of its dependencies.
Updating Needle restores it to functionality, addressing this. It also avoids
the need to add `request` to `package.json`; it also obsoletes https://github.com/mozilla/pdf.js/pull/12018.
With the changes made in PR 9659, `ColorSpace.fromIR` no longer takes a second `pdfFunctionFactory` parameter and there's thus one call-site that can be simplified.
This patch contains the following *notable* improvements:
- Changes the `ColorSpace.parse` call-sites to, where possible, pass in a reference rather than actual ColorSpace data (necessary for the next point).
- Adds (local) caching of `ColorSpace`s by `Ref`, when applicable, in addition the caching by name. This (generally) improves `ColorSpace` caching for e.g. the SMask code-paths.
- Extends the (local) `ColorSpace` caching to also apply when handling Images and Patterns, thus further reducing unneeded re-parsing.
- Adds a new `ColorSpace.parseAsync` method, almost identical to the existing `ColorSpace.parse` one, but returning a Promise instead (this simplifies some code in the `PartialEvaluator`).
This will allow caching of ColorSpaces by either `Name` *or* `Ref`, which doesn't really make sense for images, thus allowing (better) caching for ColorSpaces used with e.g. Images and Patterns.
Defining this *inline* in the "constructor" looks slightly weird (I really don't know why I wrote it like that originally), and it can simply be changed to a regular method instead.
Tweak the `QueueOptimizer` to recognize `OPS.paintImageMaskXObject` operators as *repeated* when the "skew" transformation matrix elements are non-zero (issue 8078)
As can be seen in the code there's a handful of places where this structure needs to be iterated, something that becomes cumbersome when dealing with `Object`s. Hence, by changing this to a `Map` instead we can both simplify the code and avoid creating unnecessary closures.
Particularily the `PDFPageProxy._tryCleanup` method becomes a lot more readable, at least in my opinion.
Finally, since this property is intended to be "private" the name is adjusted to reflect that.
This patch aims to simplify the `PDFPageProxy._destroy` method, by:
- Replacing the unnecessary `forEach` with a "regular" `for`-loop instead.
- Use a more appropriate variable name, since `intentState.renderTasks` contain instances of `InternalRenderTask`.
- Move the "is rendering completed"-handling to a new `InternalRenderTask.completed` getter, to abstract away some (mostly) internal `InternalRenderTask` state.
In hindsight, using the `for (let [key, value] of myMap) { ... }`-format when we don't care about the `key` probably wasn't such a great idea. Since `Map`s have explicit support for iterating either `key`s or `value`s, we should probably use that instead here.
*First of all, I should mention that my understanding of the finer details of the `QueueOptimizer` (and its related `CanvasGraphics` methods) is somewhat limited.*
Hence I'm not sure if there's actually a very good reason for *only* considering ImageMasks where the "skew" transformation matrix elements are zero as *repeated*, however simply looking at the code I just don't see why these elements cannot be non-zero as long as they are *all identical* for the ImageMasks.
Furthermore, looking at the *group* case (which is what we're currently falling back to), there's no particular limitation placed upon the transformation matrix elements.
While this patch obviously isn't enough to *completely* fix the issue, since there should be a visible Pattern rendered as well[1], it seem (at least to me) like enough of an improvement that submitting this is justified.
With these changes the referenced PDF document will no longer hang the *entire* browser, and rendering also finishes in a *reasonable* time (< 10 seconds for me) which seem fine given the *huge* number of identical inline images present.[2]
---
[1] Temporarily changing the Pattern to a solid color *does* render the correct/expected area, which suggests that the remaining problem is a pre-existing issue related to the Pattern-handling itself rather than the `QueueOptimizer` functionality.
[2] The document isn't exactly rendered immediately in e.g. Adobe Reader either.
This removes multiple instances of `// eslint-disable-next-line no-shadow`, which our old pseudo-classes necessitated.
*Please note:* I'm purposely not doing any `var` to `let`/`const` conversion here, since it's generally better to (if possible) do that automatically on e.g. a directory basis instead.
This removes one instance of `// eslint-disable-next-line no-shadow`, which our old pseudo-classes necessitated.
*Please note:* I'm purposely not doing any `var` to `let`/`const` conversion here, since it's generally better to (if possible) do that automatically on e.g. a directory basis instead.
The `isNaN` check is obviously redundant, since `NaN` is the only value that isn't equal to itself; see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/NaN#Examples
The `parseFloat`/`parseInt` comparison would make sense if the `value` ever contains a String, which however is never actually the case. Besides looking through the code, I've also run the entire test-suite locally with `assert(typeof value === "number", "encodeNumber");` added at the top of the method and there were no failures.
Hence we can simplify the "is integer" check a bit in the `CFFCompiler.encodeNumber` method.
Because of a really stupid `Promise`-related mistake on my part, when re-factoring `PDFImage.buildImage` during the `NativeImageDecoder` removal, we're no longer re-throwing errors occuring during image parsing/decoding as intended.
The result is that some (fairly) corrupt documents will never finish loading, and unfortunately there were apparently no sufficiently corrupt images in the test-suite to catch this.
For now we need to use a Babel-plugin, since Webpack 4.x doesn't seem to support it yet. (Most likely we'll have to update to Webpack 5, once that becomes available, in order for this to be directly supported. This is thus also blocked on removing the `webpack-stream` package.)
While the `??` operator will thus always be transpiled by Babel, even in modern builds, simply supporting it for development purposes seems like a step in the right direction.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing_operator
Since this is completely internal functionality, and furthermore limited to the worker-thread, this change should thus not have any observable effect for e.g. an API-user.
