effectcraft/crates/pdf

effectcraft-pdf

Vector footage from PDF files, PDF-compatible Adobe Illustrator files (.ai, which are PDF documents) and Encapsulated PostScript (.eps). Files parse into the same render tree as SVG (effectcraft_svg::Doc), so they rasterise at any scale (Continuously Rasterize), convert to shape layers (Layer ▸ Create ▸ Create Shapes from Vector Layer) and import as compositions with one layer per file layer (File ▸ Import ▸ Composition).

Specifications used: ISO 32000-1:2008 (PDF 1.7; the public Adobe edition) for the file structure, filters, content streams, graphics state, colour spaces, functions, shadings, text, fonts, images, patterns, transparency (blend modes, soft masks) and optional content; Adobe Technical Note #5176 (The Compact Font Format Specification) and #5177 (The Type 2 Charstring Format) for CFF font programs; Adobe Type 1 Font Format (version 1.1) for Type 1 font programs; the PostScript Language Reference, third edition and the Encapsulated PostScript File Format Specification 3.0 for EPS. TrueType font programs are read through skrifa and JPEG (DCT) images through zune-jpeg (both permissively licensed, pure Rust). No third-party PDF/PostScript/font code was read; test files (including the CFF and Type 1 fonts) are generated in code (write and the tests).

What is read

• Structure: indirect objects found by scanning (damaged or incremental cross-reference sections do not matter), object streams, the page tree with inherited resources, MediaBox / CropBox and /Rotate. Filters: Flate (with PNG predictors), LZW, ASCIIHex, ASCII85, RunLength. Encrypted files are refused.

• Content: q/Q, cm, line width / cap / join / miter / dash, ExtGState (CA, ca, LW, LC, LJ, ML, D), all path construction and painting operators (non-zero and even-odd), clipping (W, W*) as clipping groups, colour in DeviceGray / RGB / CMYK, ICCBased (by component count), CalGray / CalRGB, Lab, Indexed, Separation and DeviceN (tint transforms of function types 0, 2 and 3), axial and radial shadings as pattern fills and through sh, form XObjects (matrix, bounding-box clip, nested resources).

• Layers: top-level optional-content marked sequences (/OC … BDC, Illustrator's layers) become the document's layers, named after their OCG; content outside them is gathered into layers "Layer N".

• EPS: a PostScript interpreter for the subset exported vector EPS uses: operand and dictionary stacks, procedures and def/bind/load/where, arithmetic, comparisons, if/ifelse/for/repeat/loop/forall, arrays and strings, gsave/grestore, save/restore, matrices (concat, translate, scale, rotate, transform …), path construction including arc/arcn and relative operators, fill/eofill/stroke, clip/eoclip, rectfill/rectstroke/rectclip, gray / RGB / CMYK / HSB colour. DOS EPS binary headers and %%HiResBoundingBox / %%BoundingBox are honoured; %%BeginData / %%BeginBinary / preview sections are skipped.

• Text (§9): text objects and state (Tc, Tw, Tz, TL, Ts, Tr, Tf, Td, TD, Tm, T*), Tj, TJ (with kerning), ' and "; render modes fill / stroke / fill-and-stroke / invisible and the clipping modes (glyph outlines clip until Q). Glyphs become outlines (one compound shape per show operator, named "Text: …" after the string through ToUnicode or the glyph names). Fonts: simple fonts with /Widths, base encodings (Standard, WinAnsi, MacRoman), /Differences and built-in encodings; composite (Type 0) fonts with Identity-H / Identity-V and embedded CMaps (cidrange / cidchar), /W and /DW widths and CIDToGIDMap. Embedded programs: TrueType (FontFile2, cmap (3,1) / (3,0) / (1,0) and post names), CFF (FontFile3 /Type1C, /CIDFontType0C, /OpenType; name-keyed and CID-keyed with FDArray / FDSelect, flex, hint masks, seac), Type 1 (FontFile, eexec, /Subrs, flex and hint replacement through othersubrs, seac) and Type 3 glyph procedures. Fonts that are not embedded (the standard 14 and others) are drawn with the bundled OFL fonts by name: Inter (sans serif, Regular / Italic / SemiBold / Bold), Noto Serif (Times and other serif names) and JetBrains Mono (Courier), with their own advances when the PDF gives no widths.

• Images (§8.9): image XObjects and inline images (BI … ID … EI, abbreviated keys); 1, 2, 4, 8 and 16 bits per component with /Decode; any colour space above (Indexed through its palette, ICCBased through its /Alternate space); DCT (JPEG, through zune-jpeg; Adobe inverted CMYK) and the general filters; stencil masks (/ImageMask) in the fill colour; soft masks (/SMask images) and colour-key and explicit /Masks. Images become image nodes of the render tree (bilinear, box-filtered when minified).

• Transparency: blend modes (/BM, all 16 PDF modes) and soft masks in the graphics state (/SMask with /S /Luminosity and /BC backdrops, or /S /Alpha) as groups of the render tree, open until the state changes or Q.

• Patterns: tiling patterns (coloured and uncoloured, XStep / YStep, the cell clipped to /BBox, at most 4096 tiles per fill) for fills; strokes with a tiling pattern use its colour (uncoloured) or grey.

• Functions: sampled, exponential, stitching and PostScript calculator (type 4) functions.

• Pages: any page ([parse_page], [page_count]); File ▸ Import takes page (from 1) and the Import dialog asks for it; footage remembers its page (Footage::page).

Limitations

• Mesh shadings (types 4–7) and function-based shadings (type 1), JPX / CCITT / JBIG2 images, predefined CJK CMaps other than Identity, vertical metrics (/W2; vertical text advances by the font size) and transfer functions (/TR) are not read; knockout and isolated transparency groups composite as normal groups, and a soft mask applies to each painting operation while it is set rather than to their composite. What a document skipped is listed in Doc::skipped.
• Illustrator EPS files whose drawing depends on Adobe's procedure-set resources (defined in the file through constructs beyond this subset) and Level 3 shfill gradients in EPS draw only what the subset understands; save such artwork as PDF-compatible .ai or PDF instead. EPS text is not drawn.
• Create Shapes from Vector Layer: clips that enclose the whole page become layer masks (the first clip Add, later ones Intersect). Nested clipping groups become Merge Paths: each closed shape inside them is a group with its geometry merged into one compound path, the clip paths, and Merge Paths ▸ Intersect before its fill and stroke, so fills match exactly and strokes follow the clipped outline; open stroked paths inside clips stay unclipped. Blend modes become the groups' Blend Mode; images and soft masks are not converted (shape layers have no images; use the footage, or Import As: Composition).