A: tagged PDF — structure tree, figures with alt text, artifacts

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

ROADMAP.md

@@ -33,6 +33,7 @@ DesignCraft aims at full Adobe InDesign parity — and to be better: faster, ope
 - Gradient Feather (⇧G tool, `object.gradientFeather`): objects fade along a linear or radial opacity gradient, on screen and as a soft mask in PDF.
 - Script Label (`object.label`, `object.findByLabel`), alt text (`object.altText`), Isolate Blending / Knockout Group (`object.transparencyGroup`; on screen, PDF isolates), Table ▸ Sort (`table.sortRows`, numeric-aware, header/footer fixed).
 - File ▸ Export Text (`file.exportText`): a story as Text Only or RTF (fonts, styles, alignment, indents, tables as tab-separated rows); Export EPUB now asks for a path in the UI.
+- Tagged PDF (`file.exportPdf {tagged}`, on by default from the UI): structure tree with stories as paragraphs in reading order, figures carrying their alt text, parent-page items and printer's marks as artifacts.
 - Drag and drop text editing: drag selected text to move it (Alt copies) with its formatting (`text.release`).
 - Image Import Options: place any page of a multi-page PDF (`file.place {pdfPage}`; the app asks which page), shown on screen and embedded as that page in PDF export.
 - Define Lists: named numbered lists that continue across stories in page order (`list.define`, paragraph `listName` / `startAt`), round-tripped through IDML; `null` in `type.para` / `type.char` now removes an override.

crates/engine/src/cmd/export.rs

@@ -9,7 +9,7 @@ use crate::{EngineError, Result, Session};
 pub fn specs() -> Vec<CommandSpec> {
     vec![
         cmd!(noundo "file.exportPdf", "Export PDF…", ["File"], None,
-        "{path?, pages?: \"1-3,5\" | [1,3] (1-based positions; default all), spreads?: bool, bleed?: bool (document bleed), marks?: bool | {crop?, bleed?, pageInfo?, weight?, offset?}, standard?: \"none\"|\"x4\"|\"a2b\", compressImages?: bool, title?, author?} → {path, bytes, pages, warnings} (no path: {base64, …})",
+        "{path?, pages?: \"1-3,5\" | [1,3] (1-based positions; default all), spreads?: bool, bleed?: bool (document bleed), marks?: bool | {crop?, bleed?, pageInfo?, weight?, offset?}, standard?: \"none\"|\"x4\"|\"a2b\", compressImages?: bool, tagged?: bool (structure tree: stories as paragraphs, figures with alt text), title?, author?} → {path, bytes, pages, warnings} (no path: {base64, …})",
         has_doc, export_pdf),
         cmd!(noundo "file.exportEpub", "Export EPUB (Reflowable)…", ["File"], None,
         "{path?, title?, author?, language?: \"en\"} → {path, bytes} (no path: {base64, bytes})",
@@ -115,6 +115,7 @@ pub(crate) fn options(p: &Value, page_count: usize) -> Result<PdfOptions> {
         compress_images: p.get("compressImages").and_then(Value::as_bool).unwrap_or(false),
         title: str_param(p, "title").map(str::to_string),
         author: str_param(p, "author").map(str::to_string),
+        tagged: p.get("tagged").and_then(Value::as_bool).unwrap_or(false),
         ..PdfOptions::default()
     })
 }
@@ -163,3 +164,27 @@ mod text_tests {
         std::fs::remove_dir_all(&dir).ok();
     }
 }
+
+#[cfg(test)]
+mod tagged_tests {
+    use serde_json::json;
+
+    use crate::Session;
+
+    #[test]
+    fn tagged_pdf_has_structure_and_alt_text() {
+        let mut s = Session::new();
+        s.execute("file.new", &json!({})).unwrap();
+        s.execute("frame.create", &json!({"rect": [72, 72, 400, 300], "content": "text", "text": "Hello"})).unwrap();
+        let r = s.execute("frame.create", &json!({"rect": [72, 320, 200, 420]})).unwrap();
+        s.execute("object.altText", &json!({"text": "A plain box", "ids": [r["id"]]})).unwrap();
+        let pdf = |s: &mut Session, tagged: bool| {
+            let b64 = s.execute("file.exportPdf", &json!({"tagged": tagged})).unwrap()["base64"].as_str().unwrap().to_string();
+            String::from_utf8_lossy(&super::super::file::base64_decode(&b64)).into_owned()
+        };
+        let t = pdf(&mut s, true);
+        assert!(t.contains("/StructTreeRoot") && t.contains("/Figure") && t.contains("A plain box"), "tagged");
+        assert!(t.contains("/P") && t.contains("/MarkInfo"));
+        assert!(!pdf(&mut s, false).contains("/StructTreeRoot"));
+    }
+}

crates/pdf/src/export.rs

@@ -18,6 +18,7 @@ use krilla::num::NormalizedF32;
 use krilla::page::PageSettings;
 use krilla::paint::{Fill, FillRule, LinearGradient, RadialGradient, SpreadMethod, Stop, Stroke, StrokeDash};
 use krilla::surface::Surface;
+use krilla::tagging::{Artifact, ArtifactType, ContentTag, Identifier, SpanTag, Tag, TagGroup, TagTree};
 
 use crate::{ExportReport, PdfError, PdfOptions, Result, Standard};
 
@@ -151,6 +152,8 @@ pub fn export_pdf_with_report(doc: &Document, cache: &Cache, opts: &PdfOptions)
         fonts: HashMap::new(),
         reverse_cmaps: HashMap::new(),
         rgb_only: archival.is_some(),
+        tags: Vec::new(),
+        story_tags: HashMap::new(),
     };
     if ex.rgb_only {
         ex.warn("PDF/A: CMYK colours were converted to RGB (no CMYK output intent profile is available yet)");
@@ -178,7 +181,13 @@ pub fn export_pdf_with_report(doc: &Document, cache: &Cache, opts: &PdfOptions)
             ex.spread(&mut s, sh.spread);
             s.pop();
         }
+        if opts.tagged {
+            s.start_tagged(ContentTag::Artifact(Artifact::new(ArtifactType::Page, None)));
+        }
         ex.marks(&mut s, sh, &title, created);
+        if opts.tagged {
+            s.end_tagged();
+        }
         s.pop();
         s.finish();
         for a in crate::links::annotations(doc, cache, &sheets, sheet_idx) {
@@ -186,6 +195,9 @@ pub fn export_pdf_with_report(doc: &Document, cache: &Cache, opts: &PdfOptions)
         }
         page.finish();
     }
+    if opts.tagged {
+        pdf.set_tag_tree(ex.tag_tree());
+    }
     let bytes = pdf.finish().map_err(|e| PdfError::Write(format!("{e:?}")))?;
     let mut warnings = ex.warnings;
     warnings.dedup();
@@ -234,6 +246,14 @@ pub(crate) struct Exporter<'a> {
     pub reverse_cmaps: HashMap<u32, Arc<HashMap<u32, char>>>,
     /// Convert CMYK to RGB (PDF/A: krilla needs a CMYK output profile we don't ship yet).
     pub rgb_only: bool,
+    /// Tagged PDF: the structure in reading order (stories gather their frames' content).
+    tags: Vec<TagEntry>,
+    story_tags: HashMap<designcraft_doc::StoryId, Vec<Identifier>>,
+}
+
+enum TagEntry {
+    Story(designcraft_doc::StoryId),
+    Figure(TagGroup),
 }
 
 pub(crate) fn tf(a: Affine) -> Transform {
@@ -381,12 +401,12 @@ impl Exporter<'_> {
                     if parent.page_at_x(it.bounds().center().x) != Some(ppage) && parent.pages.len() > 1 {
                         continue;
                     }
-                    self.item(s, it, Affine::translate((dx, 0.0)), Some(&page_name));
+                    self.top_item(s, it, Affine::translate((dx, 0.0)), Some(&page_name), true);
                 }
             }
             for it in &sp.items {
                 if it.layer == layer.id {
-                    self.item(s, it, Affine::IDENTITY, None);
+                    self.top_item(s, it, Affine::IDENTITY, None, false);
                 }
             }
         }
@@ -420,6 +440,60 @@ impl Exporter<'_> {
         }
     }
 
+    /// A spread or parent item, inside its structure tag when tagging.
+    fn top_item(&mut self, s: &mut Surface, it: &Item, parent: Affine, page_name: Option<&str>, on_parent: bool) {
+        if !self.opts.tagged || it.hidden || it.nonprinting {
+            return self.item(s, it, parent, page_name);
+        }
+        let story = it.text_frame().map(|t| t.story);
+        let figure = !it.alt_text.is_empty() || matches!(it.content, Content::Graphic(_)) || it.has_nested_items();
+        if on_parent || (story.is_none() && !figure) {
+            // Page furniture and decoration.
+            let kind = if on_parent { ArtifactType::Page } else { ArtifactType::Other };
+            s.start_tagged(ContentTag::Artifact(Artifact::new(kind, None)));
+            self.item(s, it, parent, page_name);
+            s.end_tagged();
+            return;
+        }
+        if let Some(sid) = story {
+            let id = s.start_tagged(ContentTag::Span(SpanTag::empty()));
+            self.item(s, it, parent, page_name);
+            s.end_tagged();
+            let v = self.story_tags.entry(sid).or_default();
+            if v.is_empty() {
+                self.tags.push(TagEntry::Story(sid));
+            }
+            v.push(id);
+            return;
+        }
+        let id = s.start_tagged(ContentTag::Other);
+        self.item(s, it, parent, page_name);
+        s.end_tagged();
+        let alt = (!it.alt_text.is_empty()).then(|| it.alt_text.clone());
+        let mut g = TagGroup::new(Tag::Figure(alt));
+        g.push(id);
+        self.tags.push(TagEntry::Figure(g));
+    }
+
+    /// The structure tree: stories (one paragraph each, its frames in thread order of appearance)
+    /// and figures, in the order they first appear.
+    fn tag_tree(&mut self) -> TagTree {
+        let mut tree = TagTree::new();
+        for e in std::mem::take(&mut self.tags) {
+            match e {
+                TagEntry::Story(sid) => {
+                    let mut g = TagGroup::new(Tag::P);
+                    for id in self.story_tags.remove(&sid).unwrap_or_default() {
+                        g.push(id);
+                    }
+                    tree.push(g);
+                }
+                TagEntry::Figure(g) => tree.push(g),
+            }
+        }
+        tree
+    }
+
     fn item(&mut self, s: &mut Surface, it: &Item, parent: Affine, page_name: Option<&str>) {
         let gf = &it.effects.gradient_feather;
         if !gf.on || it.hidden || it.nonprinting {

crates/pdf/src/lib.rs

@@ -107,6 +107,9 @@ pub struct PdfOptions {
     pub author: Option<String>,
     /// Creation date as Unix seconds (UTC); `None` = now (native) / omitted (wasm).
     pub created: Option<i64>,
+    /// Tagged PDF: stories become paragraphs in reading order, graphics figures with their alt
+    /// text, parent-page items and printer's marks artifacts.
+    pub tagged: bool,
 }
 
 impl Default for PdfOptions {
@@ -122,6 +125,7 @@ impl Default for PdfOptions {
             title: None,
             author: None,
             created: None,
+            tagged: false,
         }
     }
 }

crates/ui-egui/src/menus.rs

@@ -941,6 +941,7 @@ fn export_pdf(app: &mut DesignApp, p: &Value) -> Result<Value, String> {
     if let Some(o) = params.as_object_mut() {
         o.remove("path");
         o.entry("bleed").or_insert(json!(true));
+        o.entry("tagged").or_insert(json!(true));
     }
     let r = app.run("file.exportPdf", params)?;
     let bytes = designcraft_engine::cmd::base64_decode(r["base64"].as_str().unwrap_or_default());

docs/parity.md

@@ -11,7 +11,7 @@ Each row of the InDesign feature catalogue is scored **D** (done), **P** (partia
 |---|---|---|---|---|---|
 | P0 | 102 | 99 | 3 | 0 | 99% |
 | P1 | 97 | 67 | 26 | 4 | 82% |
-| P2 | 76 | 10 | 10 | 56 | 20% |
+| P2 | 76 | 11 | 10 | 55 | 21% |
 
 | Area | Parity |
 |---|---|
@@ -33,7 +33,7 @@ Each row of the InDesign feature catalogue is scored **D** (done), **P** (partia
 | XML & automation | 50% |
 | View & navigation | 82% |
 | Undo, history, saving | 100% |
-| Accessibility | 30% |
+| Accessibility | 50% |
 
 Open P0 items: Preferences, Vector/page formats (PDF/AI/SVG/EPS place), Export to PDF (print).
 
@@ -312,7 +312,7 @@ Open P0 items: Preferences, Vector/page formats (PDF/AI/SVG/EPS place), Export t
 | Undo, history, saving | Unlimited undo/redo | P0 | D |
 | Undo, history, saving | Revert | P0 | D |
 | Undo, history, saving | Save / Save As / Save a Copy | P0 | D |
-| Accessibility | Tagged PDF export | P2 | M |
-| Accessibility | Alt text | P2 | P |
+| Accessibility | Tagged PDF export | P2 | P |
+| Accessibility | Alt text | P2 | D |
 | Accessibility | Keyboard navigation of UI | P1 | P |
 | Accessibility | High contrast | P2 | M |