diff --git a/crates/edit/src/images.rs b/crates/edit/src/images.rs index fb6212588..62bef8bc5 100644 --- a/crates/edit/src/images.rs +++ b/crates/edit/src/images.rs @@ -784,7 +784,16 @@ pub(crate) fn translate_images(doc: &mut Document, page: usize, indexes: &[usize return Err(EditError::Invalid("the image move is too large".into())); }; plans.remove(&(stream, index)); - clips.insert((stream, at), c); + // A `cm` an earlier move put before the clip takes this move too: `c · prev` is the + // same CTM as `prev` followed by another `cm c`, without one more operator per move. + let folded = at + .checked_sub(1) + .and_then(|i| Some((i, c.then(&Matrix(ops.get(i).filter(|op| op.is("cm"))?.nums::<6>()?))))) + .filter(|(_, m)| m.0.iter().all(|v| v.is_finite() && v.abs() <= 1e12)); + match folded { + Some((i, m)) => clips.insert((stream, i), (m, false)), + None => clips.insert((stream, at), (c, true)), + }; } // An image already alone in `q cm Do Q` moves by changing that `cm`, not by nesting another. let mut folds = std::collections::BTreeMap::new(); @@ -799,8 +808,8 @@ pub(crate) fn translate_images(doc: &mut Document, page: usize, indexes: &[usize folds.insert(at, folded); } let changed = crate::text::splice(&pieces, &ops, |index| { - if let Some(c) = clips.remove(&(stream, index)) { - return (vec![Op::new("cm", c.0.map(Object::Real).to_vec())], true); + if let Some((c, keep)) = clips.remove(&(stream, index)) { + return (vec![Op::new("cm", c.0.map(Object::Real).to_vec())], keep); } if let Some(m) = folds.remove(&index) { return (vec![Op::new("cm", m.0.map(Object::Real).to_vec())], false); diff --git a/crates/edit/src/tests.rs b/crates/edit/src/tests.rs index 88e3d7806..7930a7ead 100644 --- a/crates/edit/src/tests.rs +++ b/crates/edit/src/tests.rs @@ -1921,6 +1921,31 @@ fn repeated_image_edits_change_one_transform_instead_of_nesting() { } } +#[test] +fn repeated_group_moves_of_a_cropped_image_change_one_clip_transform() { + // The crop is smaller than the image, so a clip left behind would shrink `visible_rect`. + let mut doc = image_page_with("q 150 120 100 50 re W n 200 0 0 100 100 100 cm /Im0 Do Q BT /F1 12 Tf 72 700 Td (Caption) Tj ET"); + let operators = |doc: &Document| pdfcraft_content::parse(&page_content_bytes(doc, 0)).ops.len(); + let start = images::page_images(&doc, 0).unwrap()[0].clone(); + let mut first = 0; + for i in 0..20 { + images::translate_images(&mut doc, 0, &[0], [1.0, -2.0]).unwrap(); + if i == 0 { + first = operators(&doc); + } + } + let moved = |r: [f64; 4]| [r[0] + 20.0, r[1] - 40.0, r[2] + 20.0, r[3] - 40.0]; + let now = images::page_images(&doc, 0).unwrap()[0].clone(); + assert!(close(now.rect, moved(start.rect)), "{:?}", now.rect); + assert!(close(now.visible_rect.unwrap(), moved(start.visible_rect.unwrap())), "the crop moves with the image: {:?}", now.visible_rect); + assert_eq!(operators(&doc), first, "twenty group moves add no more operators than one"); + assert_eq!(q_depth(&doc), 1); + let doc = reopen(&doc); + assert!(close(images::page_images(&doc, 0).unwrap()[0].visible_rect.unwrap(), moved(start.visible_rect.unwrap()))); + let caption: Vec<_> = text::text_lines(&doc, 0).unwrap().into_iter().map(|l| l.text).collect(); + assert_eq!(caption, ["Caption"]); +} + #[test] fn page_images_move_turn_replace_and_delete() { let mut doc = image_page(); diff --git a/docs/editing-images.md b/docs/editing-images.md index eba918ef3..67d3613bf 100644 --- a/docs/editing-images.md +++ b/docs/editing-images.md @@ -8,7 +8,8 @@ together with its pixels, including nested graphics states, intervening state op and paths split across content streams. A clip shared with other content stays where it is. When the figure already sits alone in a `q … cm … Q` (its own placement, or the one an earlier edit added), moving or resizing it again changes that `cm`, so repeated edits don't -nest one more graphics state each time. +nest one more graphics state each time. Moving a privately cropped figure again likewise +changes the `cm` before its clip instead of adding another. PDF figures are not always bitmap images. Imported diagrams often use a **Form XObject**, which packages text, vector paths, and nested images into one object. PdfCraft selects