Files
vectorcraft/crates/pdf/src/lib.rs
T
Taha-Mahmoodi 2bad646821 Gradients: a Perceptual gradient mixes its colours in OKLab, and SVG and PDF write it as an image
Illustrator 30.0's gradient Method, from the public documentation
(https://helpx.adobe.com/illustrator/desktop/paint-and-fill/create-and-edit-gradients/control-perceptual-interpolation-in-gradients.html):
Classic or Perceptual; perceptual interpolation matches colour transitions to
how the eye perceives differences between colours, and perceptual gradients
are rasterised when saved as PDF or SVG.

- Gradient gains `method` (Classic | Perceptual; serde default Classic,
  written only when Perceptual, so older files open as Classic and Classic
  files are written as before). The colour crate's OKLab helpers open up for it.
- Perceptual mixes neighbouring stop colours in OKLab (sample, and
  sample_keep_model for the stroke meshes, Expand and blends); opacity stays
  linear. Renderers that mix linearly get stops on the perceptual curve,
  placed by halving each half segment where a straight line strays more than
  0.4 of a colour level (a nearly straight segment needs none). Classic
  gradients expand exactly as before.
- draws_as_pixels includes Perceptual gradients, so SVG and PDF write a
  Perceptual fill or stroke as an image at the document's raster effects
  resolution, clipped to what it paints. A gradient along or across a stroke
  stays slices (PDF no longer draws it as a within-stroke image).
- With Dither: a dithered Perceptual fill is the perceptual mix with dither's
  noise (the canvas's dithered grids are keyed by method too); SVG and PDF
  write it as an image with the noise, and a dithered Perceptual stroke as an
  image without it, as the canvas draws it (GradientPaint::pixels, SVG's
  raster_paint and PDF's area are told whether they paint a fill).
2026-10-23 01:53:29 +07:00

319 lines
12 KiB
Rust
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
//! VectorCraft PDF export and import.
//!
//! - [`export`] writes one PDF page per artboard with `krilla`: vector paths (fills, strokes with
//! caps/joins/miter/dashes, inside/outside alignment as clips, non-zero/even-odd; arrowheads,
//! width profiles, fitted or dotted dashes as the canvas's filled outlines and brushed strokes
//! as their brush art), opacity and blend modes (transparency groups),
//! clip groups, linear/radial gradients (shadings), pattern fills and strokes as their tiles and
//! freeform and Perceptual gradients and dithered gradient fills as images at the raster
//! effects resolution (clipped to what they paint), embedded images (resampled and
//! compressed as the Compression settings say) and text as outlined glyph paths, or as real
//! text in embedded subset fonts (Advanced). Colours are converted, tagged with ICC profiles and
//! given an output intent as the Output settings say. Hidden objects,
//! guides and template layers are skipped, and so are non-printing layers unless asked for.
//! Layers and sublayers can be PDF layers (optional content groups with their visibility, print
//! state and lock), and overprinting fills and strokes overprint (Advanced).
//! Each page is its artboard (the trim box) grown by the bleed (the bleed box) and by the
//! printer's marks around it (the media box), drawn in Registration. [`PdfSettings`] is the Save PDF
//! dialog's model (standard, compatibility, General, Compression, Marks and Bleeds, Output,
//! Advanced, Security); options the writer doesn't apply yet come back as warnings. With Preserve
//! Editing the native document rides along as an embedded file ([`editing()`]). Each page can
//! carry a thumbnail ([`Thumbnail`], drawn by the caller), and Fast Web View writes a linearised
//! file (still linearised when encrypted). A PDF 1.3 file ([`PdfSettings::pdf13`]) must be flat:
//! the app flattens the document first, and the writer refuses transparency that is left.
//! - [`import`] reads PDF (and PDF-compatible `.ai`) pages with `hayro-interpret` into a
//! [`Document`]: one artboard per page, and a layer per page or per optional content group
//! (with its visibility, print state and lock; art that is off comes in as a hidden layer),
//! paths with fill/stroke, clip groups, transparency groups (with isolation and knockout), soft
//! masks → opacity masks, axial/radial shadings → gradients (stop opacity and unextended ends
//! kept), mesh shadings → gradient meshes, tiling patterns → pattern swatches, images (JPEG
//! passthrough, others re-encoded as PNG) and text as point type (or glyph outlines, see
//! [`TextAs`]). Colours keep their model: CMYK, Gray, and spot
//! inks (Separation, DeviceN) as spot swatches at a tint; a file painted mostly in CMYK opens as a
//! CMYK document. [`ImportOptions`] pick the pages, the box each
//! artboard gets ([`CropTo`]) and the password; [`info`] lists the pages and their boxes.
//! The native document a PDF carries comes back too ([`ImportReport::native`], [`editing()`]),
//! and [`file_info()`] reads its File Info (the information dictionary and the XMP packet).
//! - Presets: named settings, the built-in ones generated in code ([`builtin_presets`]).
//! - [`print()`] lays a document out on paper as File → Print does ([`PrintSettings`]) and writes
//! the job as a print-ready PDF: composite or one page per ink.
//! - Security: the open and permissions passwords encrypt the written file with the standard
//! security handler, the algorithm following the compatibility ([`Encryption`]); either password
//! opens an encrypted file.
#![forbid(unsafe_code)]
mod editing;
mod encrypt;
mod export;
mod file_info;
mod forms;
mod images;
mod import;
mod import_color;
mod import_image;
mod import_lines;
mod import_mask;
mod import_scan;
mod import_shading;
mod import_text;
mod lab_spot;
mod linearize;
mod marks;
mod output;
mod pages;
mod patch;
mod pdfx;
mod post;
mod presets;
mod print;
mod settings;
mod streams;
mod syntax;
pub use editing::{EDITING_FILE, Editing, LEGACY_EDITING_FILE, editing, editing_with};
pub use encrypt::Encryption;
pub use export::{export, export_with_report, page_areas};
pub use file_info::{FileInfo, file_info};
pub use import::{
INVISIBLE_TEXT_NOTE, OFF_ARTBOARD_NOTE, OUTLINED_TEXT_NOTE, PAST_PAGE_NOTE, UNMATCHED_GLYPHS_NOTE, UNNAMED_CHARACTERS_NOTE, holds_outlines,
import, import_with_report, is_glyph_outlines, is_outlines_note,
};
pub use pages::{PageInfo, PdfInfo, has_illustrator_data, illustrator_data, info, is_postscript};
pub use post::{THUMBNAIL_SIZE, Thumbnail};
pub use presets::*;
pub use print::*;
pub use settings::*;
use vectorcraft_doc::Document;
/// Export options: the Save PDF settings plus what one export run decides (pages, title, date).
#[derive(Clone, Debug, Default)]
pub struct PdfOptions {
pub settings: PdfSettings,
/// 0-based artboard indices to export, in page order; `None` = all artboards.
pub artboards: Option<Vec<usize>>,
/// Document title for the metadata; `None` = the document's title.
pub title: Option<String>,
/// Ask PDF viewers to display the document title instead of the file name.
pub display_doc_title: bool,
/// Creation date as Unix seconds (UTC); `None` = now (native) / omitted (wasm). PDF/A needs a date.
pub created: Option<i64>,
/// Modification date as Unix seconds (UTC); `None` = the creation date.
pub modified: Option<i64>,
/// The native document (`.vectorcraft` bytes) Preserve Editing embeds.
pub native: Option<Vec<u8>>,
/// The pages drawn small, in page order: what Embed Page Thumbnails embeds (the writer
/// doesn't draw; [`page_areas`] says what each page shows).
pub thumbnails: Vec<Thumbnail>,
}
impl PdfOptions {
/// Default options with uncompressed content streams (readable operators, for tests and
/// debugging).
pub fn uncompressed() -> Self {
let compression = CompressionSettings { compress_text: false, ..Default::default() };
Self { settings: PdfSettings { compression, ..Default::default() }, ..Default::default() }
}
}
/// Import options.
#[derive(Clone, Debug)]
pub struct ImportOptions {
/// Import at most this many pages (of those picked); `None` = all of them.
pub max_pages: Option<usize>,
/// Horizontal gap in points between the artboards created for consecutive pages.
pub artboard_gap: f64,
/// 0-based pages to import, in this order; `None` = every page.
pub pages: Option<Vec<usize>>,
/// The page box each artboard gets.
pub crop: CropTo,
/// The (user) password of an encrypted PDF.
pub password: Option<String>,
/// What text becomes.
pub text_as: TextAs,
/// Optional content groups become layers (else each page is one layer, without the art
/// that is off).
pub layers: bool,
/// The file is an editor's own document (`.ai`): RGB in its `ICCBased` spaces keeps its numbers
/// (see `Colors::uncalibrated_rgb`). Off for PDFs, whose profiles stand.
pub uncalibrated_rgb: bool,
}
impl Default for ImportOptions {
fn default() -> Self {
Self {
max_pages: None,
artboard_gap: 36.0,
pages: None,
crop: CropTo::default(),
password: None,
text_as: TextAs::default(),
layers: true,
uncalibrated_rgb: false,
}
}
}
settings::choice! {
/// What imported text becomes.
TextAs {
/// Point type, one object per line run, in the file's fonts (by name).
Text = "text", "Text";
/// Paths of the glyphs' outlines (looks the same without the fonts).
Outlines = "outlines", "Outlines";
} default Text
}
settings::choice! {
/// The page box an imported or placed page is cropped to: its artboard (or placed frame).
CropTo {
/// The bounds of the page's art.
Bounding = "bounding", "Bounding Box";
Art = "art", "Art";
/// The visible page area (what viewers show).
Crop = "crop", "Crop";
/// The finished page: an import takes the bleed box round it as the document's bleed.
Trim = "trim", "Trim";
Bleed = "bleed", "Bleed";
/// The whole sheet.
Media = "media", "Media";
} default Crop
}
/// Result of an import with non-fatal warnings (unsupported features, skipped content).
#[derive(Clone, Debug)]
pub struct ImportReport {
pub document: Document,
pub warnings: Vec<String>,
/// The native document the PDF carries (written with Preserve Editing), if any.
pub native: Option<Editing>,
/// Every page shows only text, over an editor's private data: that data, where it reads,
/// is the file's art (a file saved without its PDF part shows a notice there instead).
pub only_text: bool,
/// The size in points of a unit of the first page read's user space: the `UserUnit` the PDF
/// reader applies to that page (1 for a page without one). The page came in at its size in
/// points, its numbers times this.
pub user_unit: f64,
}
/// Result of an export with non-fatal warnings (features approximated or dropped).
#[derive(Clone, Debug)]
pub struct ExportReport {
pub bytes: Vec<u8>,
pub warnings: Vec<String>,
}
#[derive(Debug, thiserror::Error, PartialEq)]
pub enum PdfError {
#[error("the document has no artboards")]
NoArtboards,
#[error("artboard {0} does not exist")]
BadArtboard(usize),
#[error("unsupported: {0}")]
Unsupported(String),
#[error("PDF writer error: {0}")]
Write(String),
/// The caller asked for the export to stop ([`vectorcraft_doc::cancel`]).
#[error("cancelled")]
Cancelled,
#[error("cannot read PDF: {0}")]
Parse(String),
#[error("the PDF has no pages")]
NoPages,
#[error("invalid PDF setting: {0}")]
BadSetting(String),
#[error("the PDF is password-protected: give its password")]
NeedsPassword,
#[error("the PDF password is wrong")]
WrongPassword,
#[error("page {0} does not exist (the PDF has {1})")]
BadPage(usize, usize),
#[error(
"this is a PostScript file (an .ai saved in an older format or without PDF compatibility, or an EPS file), not a PDF: File › Open and File › Place read it as EPS"
)]
PostScript,
#[error(
"the file holds only a placeholder page, not its art (it was saved without PDF compatibility): save it again with PDF compatibility on, or as PDF or SVG"
)]
PlaceholderOnly,
}
impl From<craft_pdf::write::WriteError> for PdfError {
fn from(error: craft_pdf::write::WriteError) -> Self {
Self::Write(error.to_string())
}
}
#[cfg(test)]
mod tests;
#[cfg(test)]
mod tests_blend;
#[cfg(test)]
mod tests_charstroke;
#[cfg(test)]
mod tests_cmykblend;
#[cfg(test)]
mod tests_cmykimages;
#[cfg(test)]
mod tests_compression;
#[cfg(test)]
mod tests_dashalign;
#[cfg(test)]
mod tests_editing;
#[cfg(test)]
mod tests_encrypt;
#[cfg(test)]
mod tests_file_info;
#[cfg(test)]
mod tests_focal;
#[cfg(test)]
mod tests_fx;
#[cfg(test)]
mod tests_import_color;
#[cfg(test)]
mod tests_import_fidelity;
#[cfg(test)]
mod tests_import_layers;
#[cfg(test)]
mod tests_import_lines;
#[cfg(test)]
mod tests_import_options;
#[cfg(test)]
mod tests_import_overprint;
#[cfg(test)]
mod tests_layers;
#[cfg(test)]
mod tests_live_text;
#[cfg(test)]
mod tests_marks;
#[cfg(test)]
mod tests_output;
#[cfg(test)]
mod tests_pdf13;
#[cfg(test)]
mod tests_pdfx;
#[cfg(test)]
mod tests_presets;
#[cfg(test)]
mod tests_print;
#[cfg(test)]
mod tests_printadvanced;
#[cfg(test)]
mod tests_realtext;
#[cfg(test)]
mod tests_settings;
#[cfg(test)]
mod tests_stroke;
#[cfg(test)]
mod tests_strokeout;
#[cfg(test)]
mod tests_textstroke;
#[cfg(test)]
mod tests_webview;
#[cfg(test)]
mod tests_reader_streaming;
#[cfg(test)]
mod tests_reader_compat;