The PostScript Language Reference (3rd ed., §3.7.3 "Save and Restore")
has `restore` reset composite objects in local VM to their values at the
`save`. The reader only restored the graphics state, so dictionary
entries changed between `save` and `restore` stayed changed: a program
that counts its open saves in a dictionary and refuses to go past a depth
stopped after that many saves in sequence, and the file fell back to its
preview. EPS files with many images, each drawn between `save` and
`restore`, are a likely case of #505; its reporter hasn't sent a file, so
this is part of it.
- While a `save` is open, `def`, `store`, `put`, `undef` and dictionary
`copy` keep each entry's old value in a journal (counted against the
memory budget); `restore` undoes it, newest change first, down to its
save. A save restored already, itself or through an outer one, is no
longer valid (`invalidrestore`, §3.7.3).
- `cachestatus` reports a device's cache sizes (chapter 8) instead of
zeros: its last value, the most bytes one cached glyph may take, is what
programs divide by.
- Tests (programs written from the reference): 100 saves counted in a
dictionary under a depth limit, each dictionary change undone, saves
restored twice, `cachestatus`'s glyph limit. Mutation-checked: without
the journal or with a zero `cachestatus` the test fails. The import fuzz
vocabulary has saves and restores around dictionary changes.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
An image can take one data source per colour component
(MultipleDataSources, or `colorimage` with multi true). The PostScript
Language Reference (3rd ed., §4.10 "Images" and `image`/`colorimage` in
chapter 8) has the operator read the sources in turn, the same amount
from each. The reader drained each source on its own instead: when the
sources are procedures reading one file a row at a time, the first plane
took the rows of every component and the image came out in sheared
horizontal bands, as in #498.
- Data sources are read in turn by one reader, `read_sources`: a procedure
once a round, a file or string a row a round, until each plane is full or
its source ends. Single sources, procedure filters and masked images use
it too; a string source resumes where it left off.
- Tests (`tests_images.rs`, programs written from the reference):
procedures reading one file in the dictionary and `colorimage` operand
forms (fails without the fix), separate string sources, rows padded to a
byte at 1, 2, 4, 12 and 16 bits with an odd width (one and several
sources), Flate PNG predictors with every row filter at an odd width.
The import fuzz vocabulary has several sources reading one file and
sources of uneven lengths.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Two EPS import tests become programs written from the PostScript Language
Reference (3rd ed.), with their own names and structure, covering the
interpreter features the importer relies on:
- `level_2_and_3_probes_read_as_vectors`: a resource category made from
Generic, resources defined and found in it (§3.9), local and global VM
(`currentglobal`, `setglobal`, `gcheck`, §3.7.2), `internaldict` probed
through `stopped`, a halftone dictionary set and restored, `cachestatus`,
`rootfont` and `currentcolorrendering`, drawing with its own procedures.
- `executable_strings_and_integer_keys`: shading dictionaries closed by an
executable string (`(>>) cvx`, or a Level 1 builder with `counttomark`),
procedures kept under integer keys run with `load` through `stopped`,
`cvx`/`cvlit`/`xcheck` on strings.
Each was mutation-checked: making any of findresource, defineresource,
currentglobal, setglobal, gcheck, internaldict, sethalftone,
currenthalftone, currentcolorrendering, cachestatus, rootfont, stopped,
cvx, load, counttomark, cvlit or xcheck unknown fails a test, and so do
strings that `cvx` leaves literal, `load` refusing integer keys and
`gcheck` answering true.
The ROADMAP's EPS paragraph, file-formats row and last-updated line state
the PostScript features the reader supports; the legacy `.ai` comments in
the import module and the interpreter cite that format's published
specification (PRONOM fmt/423) for the `%AI` header comments and `u`/`U`
group operators the reader keys on.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Stock EPS files saved in the Illustrator 8 format failed with "typecheck in `a
dictionary`": its gradient procset builds shading dictionaries with `bd` …
`ed`, where `ed` is `(>>) cvx` (or a Level 1 dictionary builder as a
string), and `cvx` left a string literal, so `shfill` got a string. Its
`discard` procedure also `load`s procedures by integer keys, which `load`
refused.
- Executable strings: `cvx` makes a string executable (`xcheck` true,
`cvlit` back, still a `stringtype` for `length`/`get`/`forall`/
`getinterval`); run by name or met in a procedure, it runs its text as a
program, every time (an executable file shares the same runner).
- `load` takes any key (integers, booleans), as `where` already did.
- Test: an Illustrator 8-style gradient procset with both `ed` forms and
`discard`; the import fuzz vocabulary has executable strings and integer
keys. An Illustrator 2026 file saved in the Illustrator 8 format (made
here, not committed) now opens as vectors with its radial gradient.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Discord feedback: "EPS files are always rasterized: they open as bitmaps, in
other programs as vectors". Every EPS saved by Illustrator 2026 fell back to
its TIFF preview (`gcheck` was unknown), and cairo/Inkscape files stopped at
their first image (`status`), dropped masked images (ImageType 3) and failed
on mesh gradients; the warning didn't say where the program failed.
Fallback never silent:
- The warning names the PostScript error, the operator that raised it and
the named procedures it ran in, innermost first ("a PostScript error
(typecheck in `add`), in `inner` in `outer`"); errors caught by `stopped`
aren't reported. It reaches the status bar, document.open, app.open and
file.open (which now return document.open's result, so MCP's open_file over
the control channel gets it), and `vectorcraft-cli info` ("warnings").
- A file whose PostScript can't be read opens as its TIFF preview, else its
Windows metafile preview (as vectors, scaled to the bounding box), else its
EPSI bitmap. es @msg rows for the new messages.
Interpreter:
- Operators programs probe or use: gcheck/scheck, rootfont,
currentcolorrendering, currenthsbcolor, status, token, read,
bytesavailable, fileposition/setfileposition, resetfile, write*, pdfmark
(marks dropped, as Ghostscript does), execform, nulldevice, strokepath,
pathforall, user paths (ufill/ueofill/ustroke/uappend/upath/setbbox, the
encoded form too), setcachedevice2, findcolorrendering, cache, device and
VM queries, revision; (%stdout) (w) file gives a sink.
- `//name` is replaced by its value when read, inside procedures too.
- Tiling patterns become pattern swatches (their PaintProc drawn in pattern
space, one cell; uncoloured ones in the colour under them; makepattern
copies share one swatch); nested patterns stop at 8 levels.
- Type 3 fonts draw their glyphs (BuildGlyph/BuildChar, widths from
setcachedevice/setcharwidth) as outlines grouped per string, spaced by
ashow/widthshow/awidthshow/xshow/yshow/xyshow/kshow; glyphshow and
stringwidth/cshow use them.
- Shadings of types 1 and 4-7 become gradient meshes (data from arrays,
strings or files, packed or not, flags sharing edges), as fills through a
shading pattern too; sampled functions (type 0) are evaluated;
GradientMesh::coons/triangle are shared with PDF import.
- ImageType 3 masked images, interleaved by sample, by row or in separate
sources; ReusableStreamDecode reads its data when made; Flate/LZW PNG and
TIFF predictors.
- Bounded: DeviceN at 32 inks, sampled functions at 2^24 samples and 32
outputs, 4096 patches a shading, strokepath ignores dashes finer than 1e5
pieces, Type 3 glyphs nest 8 deep (a glyph that shows itself overflowed the
stack before the limit), 64-bit index maths for 32-bit targets.
Tests: a synthetic program per generator (cairo/Inkscape, its Type 3 fonts,
matplotlib, CorelDRAW, Affinity, LibreOffice, Ghostscript eps2write,
Illustrator procsets), meshes and function shadings, masked images, fault
messages, probing operators, metafile/EPSI previews, `//name`, user paths,
hostile patterns/glyphs/shadings (run against main, 12 of the 14 generator
and feature tests fail; CorelDRAW- and LibreOffice-style programs already
read there). The import fuzz vocabulary covers the new operators. Checked
against real files made here with Inkscape 1.4 (cairo) and Illustrator 2026
(its own format and the CS-to-CC compatibility formats; all fell back or
stopped early on main and open as vectors now; its Illustrator 8 format
needs the next commit); those files aren't committed.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
