setGStateForKey() is a closure that serves no particularly useful
purpose. This change inlines it at the single call site. This avoids 1.7
MiB of allocations (because closures are objects) for the MTA map
mentioned in https://bugzilla.mozilla.org/show_bug.cgi?id=835380#c17.
For the document in #2504, 11% of the ops are `setGState` with a
`gStateObj` that is an empty array, which is a no-op. This is possible
because we ignore various setGState keys (OP, OPM, BG, etc).
This change prevents these ops from being inserted into the operator
list.
EvaluatorPreprocessor_read() is called in two cases. For the normal
layer, the args array it produces is used beyond the bounds of the loop
in which EvaluatorPreprocessor_read() is called.
But for the text layer, the args array is used in a very short-term
fashion. This change reworks things so that a single array is repeatedly
used for the text layer. This reduces total JS allocations for the
Spoorkaart map by 11%, and has similar effects on many other PDFs.
After PR 4982, the rendering of the first two pages of http://www.openmagazin.cz/pdf/2011/openMagazin-2011-04.pdf (from issue 215) no longer completes.
The issue is that we cannot have `args === null` in `PartialEvaluator_buildPath`, but *must* use an empty array instead.
In this patch I've also moved the `argsLength` variable definition in `EvaluatorPreprocessor_read`, to make sure that it's always defined.
QueueOptimizer is really hard to read. Enough so that it's blocking my
efforts to streamline the representation used for operator lists.
This patch improves its readability in the following ways.
- More descriptive variable names make the sequence checking much clearer,
as do additional comments.
- The addState() functions now return the index of the first op past the
sequence, instead of setting context.currentOperation to the last op of
the sequence.
- The loop in optimize() is clearer.
- The array modification in the fourth addState() function is much clearer
-- we're just removing trios of ops.
- All four |addState| functions are now more consistent with each other.
I used some debug printfs to find documents where these optimizations are
used and then checked that the number of optimized ops was the same before
and after my changes.
This function can be called 100s of 1000s or even millions of times, and the
allocated return object accounts for 10% of all GC thing allocations for some
documents. It's easy to avoid, which reduces stress on the garbage collector,
and this patch does that.
PartialEvaluator.getTextContent() builds up textChunk strings 1 char at a time,
creating many 100s of 1000s of intermediate strings along the way. This patch
make it instead push chars to an array and then join them at the end, as we
have done in numerous other places.
The function `assertWllFormed` was doing nothing different than `assert` which is
available in the same namespace. Removing it will lighten the filesize - albeit
very slightly - and reduce complexity.
Different fonts can point to the same font descriptor
(see https://github.com/mozilla/pdf.js/issues/4339 for details). With this
commit such fonts are treated as aliases if they have also the same encoding
and the same toUnicode map. The according info is stored on the font descriptor.
This change must also ensure that aliases use always the same font name
because translated fonts can get cleared depending on the CLEANUP_TIMEOUT setting.
This makes the code much simpler, and the extra memory use is tiny -- a vanilla
1000 element array is only 4000 bytes larger than a Uint32Array of the same
size.
When decoding a stream, the decode buffer is often grown multiple times, its
byte size increasing like so: 512, 1024, 2048, etc. This patch estimates the
minimum size in advance (using the length of the encoded stream), often
allowing the smaller sizes to be skipped. It also renames numerous |length|
variables as |maybeLength| to make it clear that they can be |null|.
I measured this change on eight documents. This change reduces the cumulative
size of decode buffer allocations by 0--32%, with 10--20% being typical. This
reduces peak RSS by 10 or 20 MiB for several of them.
Added an "InteractiveAnnotation" class to homogenize the annotations' structure (highlighting) and user interactions (for now, used for text and link annotations).
Text annotations:
The appearance (AP) has priority over the icon (Name).
The popup extends horizontally (up to a limit) as well as vertically.
Reduced the title's font size.
The annotation's color (C) is used to color the popup's background.
On top of the mouseover show/hide behavior, a click on the icon will lock the annotation open (for mobile purposes). It can be closed with another click on either the icon or the popup.
An annotation printing is conditioned by its "print" bit
Unsupported annotations are not displayed at all.
