This PR is related to GH-20732, which is about `AuthEvent` (to delay
promting for a password), but instead adds the actual support for
encrypted attachments.
“Encrypted attachments” means that the main things are plain text.
Note that some PDF viewers, like Preview/QuickLook/Safari or Chrome,
do not support attachments at all.
Note that the file checked into the tests is the same as
`output-no-auth-event.pdf` referenced in
<https://github.com/mozilla/pdf.js/issues/20139#issuecomment-3952462166>.
Closes GH-20139.
It fixes#7625.
If the Top DICT's Private DICT extends past the end of the font data,
the Local Subrs INDEX is unreachable and every CharString that calls
a subr ends up as a blank glyph. Throw from parsePrivateDict so the
existing catch in translateFont triggers fallbackToSystemFont, then
run getFontSubstitution post-construction so we pick a close local
match instead of the generic fallbackName.
Some Type1 fonts (the embedded Optima variants in orw1972.pdf) ship
two /Subrs and /CharStrings blocks wrapped in save/restore frames
gated on an Adobe hires/lores runtime switch.
In such cases, we just use the first /Subrs and /CharStrings block,
which is the one that is actually used by the font renderer in Acrobat.
It fixes#18548.
When a CIDFontType0 descendant has its program in a FontFile3 stream with
/Subtype /OpenType, the OTF wrapper sometimes lacks a usable cmap and the
CID→GID mapping only exists inside the embedded CFF itself. In that case
the OpenType-table path produces wrong glyphs, so route the font through
CFFFont and let it consume the inner CFF directly.
The file has been found in https://issues.chromium.org/issues/471404119.
It fixes#18032.
Only use the special inner-backdrop compositing path for nested non-isolated groups that actually need isolation.
This preserves the parent/page backdrop for simple nested groups inside knockout groups, preventing later group
compositing from erasing existing backdrop content.
Test PDF files should never be executable because we only read their
contents, so this commit makes sure that all test PDFs have the same
permissions, namely 0644 (read-only for all groups, and writable for the
owner), to limit their permissions for a least-privilege approach.
In a knockout (KO) group each painting operator ("element") composites against
the group's initial backdrop instead of accumulating onto prior elements
of the same group. The backend renders each element to a per-group pooled
temp canvas (keyed off `#groupStackMeta`), builds a binary alpha mask via
a new `feFuncA` filter (`addKnockoutFilter`), `destination-out`s the
group canvas through that mask, restores the initial backdrop into the
cleared footprint for non-isolated groups (cropped to the same mask so
sparse groups don't bleed the whole rectangle), and finally paints the
element on top with the parent's blend mode. Path / clip / transform ops
are mirrored back to the group canvas via `mirrorContextOperations` so
graphics state stays in sync between elements; only the raster pixels
land on the temp canvas.
The temp canvas is forced to source-over for the element raster (`multiply`
on a transparent backdrop would zero the color) and the original GCO is
restored before `copyCtxState` writes back, so the parent's blend mode
survives for the final composite.
Also handled:
- Nested KO groups (the level is incremented for KO, reset to 0 for
non-KO subgroups so an ancestor KO doesn't leak in).
- Non-isolated non-KO subgroups inside a KO parent (`hasInnerBackdrop`
path: blend the elements against the subgroup's running backdrop for
color, mask with the elements-only canvas).
- Soft masks installed inside a KO element (`applySMaskInPlace` in
`compose`, which runs the SMask destination-in directly on the temp
canvas; the existing blit-to-suspended step is gated by `if (!ctx)`).
- Type-3 text, shading fills, image-mask groups, inline images and the
solid-color mask path: each is wrapped in `#begin/#endKnockoutElement`.
- `endDrawing` cleanup so cancelled rendering doesn't leak pooled
canvases or stale knockout state.
Prepare reusable soft-mask canvases for filtered and backdrop-dependent masks,
and use a faster destination-in composition path where possible.
Handle Alpha SMask /BC correctly, preserve OOB alpha behavior, and mirror canvas path
operations needed while rendering inside soft-mask mode (mirrored clip was buggy).
Add reftest PDFs covering Alpha masks, transfer functions, backdrop/OOB
alpha, and the optimized composition paths.
1. Record `fill` dependencies even if we early return due to `isPatternFill``
2. Isolate the `drawPattern` inner `executeOperationList` in a
`CanvasNestedDependencyTracker` so that it does not consume pending
dependencies from the outer list.
This test-case is an especially "bad" one performance wise given its PostScript function use, when falling back to the (now removed) `PostScriptEvaluator` code.
It fixes#5046.
We just generate a mesh for the pattern rectangle where the color of each vertex is computed from the function.
Since the mesh is generated in the worker we don't really take into account the current transform when it's drawn.
That being said, there are maybe some possible improvements in using directly the gpu for the shading creation
which could then take into account the current transform, but it could only work with ps function we can convert
ino wgsl language and simple enough color spaces (gray and rgb).
