Merge pull request #3927 from storytold/fix/1479-ai-large-images

.ai import: an image too large for the editing data's reader opens the file as its PDF part, not with a blank layer (#1479)

crates/eps/src/import/ai/mod.rs

@@ -31,7 +31,7 @@ use super::lex::find;
 use crate::ps;
 
 pub(crate) use frames::text_frames;
-pub use read::{Structure, artboards, read, variables};
+pub use read::{IMAGE_TOO_LARGE, Structure, artboards, read, variables};
 pub(crate) use read::{slot_frame, slot_of};
 
 #[cfg(test)]

crates/eps/src/import/ai/read.rs

@@ -76,6 +76,9 @@ const MAX_NODES: usize = 4_000_000;
 const MAX_POINTS: usize = 4_000_000;
 /// Largest image read (pixels).
 const MAX_PIXELS: u64 = 1 << 25;
+/// The note for an image past [`MAX_PIXELS`]: the file then opens from its PDF part, which reads
+/// larger images (#1479).
+pub const IMAGE_TOO_LARGE: &str = "an image too large to read from the editing data was left out";
 /// Most hex digits of an image's samples read from comment lines (CMYK and alpha at the largest size).
 const MAX_HEX: usize = (MAX_PIXELS as usize) * 10;
 /// Largest side of the document and its artboards (points).
@@ -2096,7 +2099,11 @@ impl<'a> Reader<'a> {
             return Ok(());
         };
         let (w, h) = (*w as u64, *h as u64);
-        if w == 0 || h == 0 || w.saturating_mul(h) > MAX_PIXELS || ![1.0, 8.0].contains(bits) {
+        if w.saturating_mul(h) > MAX_PIXELS {
+            self.warn(IMAGE_TOO_LARGE);
+            return Ok(());
+        }
+        if w == 0 || h == 0 || ![1.0, 8.0].contains(bits) {
             self.warn("an image VectorCraft can't read was left out");
             return Ok(());
         }

crates/eps/src/import/native.rs

@@ -1401,20 +1401,27 @@ pub fn layered_ai(private: &[u8], visible: Document, warnings: Vec<String>, outl
     if !has_layers(&data) {
         return (visible, warnings, false);
     }
+    // The PDF part, its pages placed and named as the editing data's artboards are, when the
+    // layers can't be used (`why`).
+    let from_pdf_part = |mut visible: Document, warnings: Vec<String>, why: &str| {
+        place_pages(&ai::artboards(&data), &mut visible, unit);
+        let mut all = unread(warnings, why);
+        all.extend(ai::variables(&data).note());
+        (visible, all, false)
+    };
     match build(&data, Some(&visible), Page::Artboard, outlined, trust, unit) {
+        // An image too large for the editing data's reader would be missing from the layers, while
+        // the PDF part has it: the file comes in as its PDF part instead (#1479).
+        Ok((_, notes)) if notes.iter().any(|n| n == ai::IMAGE_TOO_LARGE) => {
+            from_pdf_part(visible, warnings, "an image is too large to read from them")
+        }
         Ok((mut done, notes)) => {
             done.setup.bleed = visible.setup.bleed;
             let mut all = warnings;
             all.extend(notes.into_iter().filter(|n| !all.contains(n)).collect::<Vec<_>>());
             (done, all, true)
         }
-        Err(why) => {
-            let mut visible = visible;
-            place_pages(&ai::artboards(&data), &mut visible, unit);
-            let mut all = unread(warnings, &why);
-            all.extend(ai::variables(&data).note());
-            (visible, all, false)
-        }
+        Err(why) => from_pdf_part(visible, warnings, &why),
     }
 }
 

crates/eps/src/import/tests_native.rs

@@ -243,6 +243,29 @@ fn in_points(mut d: Document, k: f64) -> Document {
     d
 }
 
+/// #1479: an image larger than the editing data's reader takes would be missing from the layers,
+/// while the PDF part has it (it reads larger images): the file comes in as its PDF part, with a
+/// note saying why, rather than without the image.
+#[test]
+fn an_ai_file_with_an_image_too_large_for_its_editing_data_comes_in_as_its_pdf_part() {
+    let raster = |w: u32, h: u32| {
+        format!(
+            "%AI5_File:\n%AI5_BeginRaster\n() 1 XG\n/DeviceGray XN\n[ 1 0 0 1 0 100 ] {w} {h} 0 Xh\n\
+             [ 1 0 0 1 0 100 ] 0 0 {w} {h} {w} {h} 8 1 0 0 1 0 4 4 0 0\n%%BeginData: 1\rXI\n\u{0}%%EndData\r\nXH\r\n%AI5_EndRaster\r\nN"
+        )
+    };
+    // 6,000 × 6,000 pixels: past the reader's 2^25.
+    let art = native(&layer("Texture", true, &format!("{}\n{}", square(10, 10), raster(6000, 6000))));
+    let (d, warnings, read) = crate::layered_ai(&private(&art), pdf_part(10.0, 86.0), vec![], false, true, 1.0);
+    assert!(!read, "the PDF part is used: {warnings:?}");
+    assert!(warnings.iter().any(|w| w.contains("an image is too large to read from them")), "{warnings:?}");
+    assert_eq!(d.layers[0].children().map_or(0, |c| c.len()), 1, "the PDF part's art");
+    // An image the reader takes keeps the layers.
+    let art = native(&layer("Texture", true, &format!("{}\n{}", square(10, 10), raster(1, 1))));
+    let (_, warnings, read) = crate::layered_ai(&private(&art), pdf_part(10.0, 86.0), vec![], false, true, 1.0);
+    assert!(read, "{warnings:?}");
+}
+
 #[test]
 fn an_ai_file_gets_its_layers_and_the_art_outside_its_artboard() {
     // A square on the artboard, and one above it (the artboard is y 0 to 100 here).

docs/file-format-parity.md

@@ -130,6 +130,7 @@ the app's own editing copy of a file (an EPS after its `%%EOF`, a `.ai`'s `AIPri
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-10-24 | minor | `.ai` import: an image larger than the editing data's reader takes (2^25 pixels, a halftone texture at print resolution) no longer leaves its layer blank: the file comes in as its PDF part, which reads larger images, with a note saying why (#1479). Own-fixture test; scores and hours unchanged |
 | 2026-10-24 | minor | PDF export: a pattern fill or stroke is written as a PDF tiling pattern (ISO 32000-1, 8.7.3.1) of one period of the tiling, as the canvas repeats it, so grid, brick and hex tilings and overlapping tiles keep their look in a few kilobytes, and PDF import reads it back as one object with a pattern swatch instead of hundreds of tile paths (#3849). Patterns nested more than four deep, or with tiles beyond a billion points, are still written as their tiles, now with a warning. Tests: the issue's hatch round trip, a brick tiling read back against the canvas, the nesting warning; scores and hours unchanged |
 | 2026-10-23 | minor | SVG: type written as outlines stacks each run's colour glyphs (bitmap images, COLR and SVG art) under the run's paint, as the canvas does, so a plain character set over a colour one stays on top; scores unchanged |
 | 2026-10-23 | minor | PDF import: a line's spacing is measured from the file's own glyph widths, so type in a font the file doesn't carry, drawn with an installed font whose advances its widths round off (Helvetica on macOS: 2048 units an em), keeps one tracking value on its letters instead of a run per character (#722 follow-up); test with built-in Inter, independent of the fonts installed; scores and hours unchanged |