diff --git a/crates/edit/src/images.rs b/crates/edit/src/images.rs index f4680bcc5c..72656fa1bb 100644 --- a/crates/edit/src/images.rs +++ b/crates/edit/src/images.rs @@ -1691,6 +1691,12 @@ pub(crate) fn selectable_images( .collect()) } +/// Whether an XObject drawn at or after operator `from` of the page's joined operators shows +/// inside `rect` (user space). +pub(crate) fn painted_over(doc: &Document, page: usize, rect: [f64; 4], from: usize) -> Result { + Ok(page_images(doc, page)?.iter().any(|i| i.op >= from && i.visible_rect.and_then(|v| intersection(v, rect)).is_some())) +} + fn transform_image( doc: &mut Document, page: &pdfcraft_model::Page, diff --git a/crates/edit/src/lib.rs b/crates/edit/src/lib.rs index 44a6730acc..b95c4296f9 100644 --- a/crates/edit/src/lib.rs +++ b/crates/edit/src/lib.rs @@ -77,7 +77,7 @@ use marks::{matrix_number, n}; pub(crate) use place::undrawable; #[cfg(test)] use place::{ISOLATION_MAX_DEPTH, OLD_WRAP_CLOSE, WRAP_CLOSE, WRAP_OPEN, is_wrap_close, page_fonts, stream_bytes, stream_tag, tagged, wrapper_role}; -use place::{check, check_on_top, contents, page_list, place_tagged}; +use place::{Reach, check, check_on_top, contents, draw_on_top, lift_on_top, page_list, place_tagged, revealed_under_paint}; pub use place::{stamp, undrawable_message}; #[cfg(test)] diff --git a/crates/edit/src/place.rs b/crates/edit/src/place.rs index b535d60563..27ed7b3793 100644 --- a/crates/edit/src/place.rs +++ b/crates/edit/src/place.rs @@ -371,6 +371,76 @@ pub(crate) fn place_tagged(doc: &mut Document, page: &pdfcraft_model::Page, tag: Ok(mark_ref) } +/// Draw `ops`, written for the space whose CTM is `ctm`, on top of everything on `page`, tagged +/// `Edited`. A rewritten invisible paragraph goes here when [`revealed_under_paint`]: an OCR +/// layer written before the scan image it lies under would keep the revealed text hidden (#3973). +pub(crate) fn draw_on_top(doc: &mut Document, page: &pdfcraft_model::Page, ctm: [f64; 6], ops: &[pdfcraft_content::Op]) -> Result<(), EditError> { + if ops.is_empty() { + return Ok(()); + } + use pdfcraft_content::Op; + let mut all = vec![Op::new("q", vec![]), Op::new("cm", ctm.iter().map(|v| pdfcraft_content::num(*v)).collect())]; + all.extend_from_slice(ops); + all.push(Op::new("Q", vec![])); + place_tagged(doc, page, "Edited", pdfcraft_content::serialize_ops(&all), false).map(drop) +} + +/// Where a rewritten paragraph can be drawn, in user space ([`revealed_under_paint`]). +pub(crate) struct Reach { + /// The paragraph's old box, where its cover goes. + pub rect: [f64; 4], + /// The move asked for (`BlockStyle::offset`). + pub offset: [f64; 2], + /// The widest line the rewrite may draw, how many lines it has, and how far apart they are. + pub width: f64, + pub rows: usize, + pub pitch: f64, + pub upright: bool, +} + +impl Reach { + /// The old box and the moved one, grown to `width` either way (alignment may grow a line left + /// or right), down to `rows` lines and up one `pitch` above its top (a larger size on the first line, however many lines the old box had); turned text grows by the lines' diagonal every way. + /// Unbounded when a number is not finite. + pub(crate) fn bounds(&self) -> [f64; 4] { + const UNBOUNDED: [f64; 4] = [f64::NEG_INFINITY, f64::NEG_INFINITY, f64::INFINITY, f64::INFINITY]; + let ([dx, dy], r) = (self.offset, self.rect); + if !r.iter().chain(&self.offset).chain([&self.width, &self.pitch]).all(|v| v.is_finite()) { + return UNBOUNDED; + } + let moved = [r[0] + dx, r[1] + dy, r[2] + dx, r[3] + dy]; + let rows = f64::from(u32::try_from(self.rows).unwrap_or(u32::MAX)); + let (width, height) = (self.width.abs(), self.pitch.abs() * rows); + let grown = if self.upright { + [moved[0].min(moved[2] - width), moved[1].min(moved[3] - height), moved[2].max(moved[0] + width), moved[3] + self.pitch.abs()] + } else { + let d = width.hypot(height); + [moved[0] - d, moved[1] - d, moved[2] + d, moved[3] + d] + }; + let b = [r[0].min(grown[0]), r[1].min(grown[1]), r[2].max(grown[2]), r[3].max(grown[3])]; + if b.iter().all(|v| v.is_finite()) { b } else { UNBOUNDED } + } +} + +/// Whether a rewritten paragraph that was `invisible` goes on top of page `page`: something after +/// operator `at` of the page's joined `ops` paints over `reach` (user space, [`Reach::bounds`]), as the scan image +/// does over an OCR layer written before it (#3973). XObjects count where they are drawn; an inline +/// image or a shading after it counts anywhere, and so does any XObject when the page's images +/// cannot be listed. +pub(crate) fn revealed_under_paint(doc: &Document, page: usize, invisible: bool, reach: [f64; 4], ops: &[pdfcraft_content::Op], at: usize) -> bool { + let later = ops.get(at..).unwrap_or_default(); + if !invisible || later.iter().any(|op| op.is("BI") || op.is("sh")) { + return invisible; + } + later.iter().any(|op| op.is("Do")) && crate::images::painted_over(doc, page, reach, at).unwrap_or(true) +} + +/// The operators to draw on top of the page ([`draw_on_top`]): all of `paragraph` when `over`, +/// none otherwise. The page was checked to take them ([`check_on_top`]) before the edit began. +pub(crate) fn lift_on_top(over: bool, paragraph: &mut Vec) -> Vec { + if over { std::mem::take(paragraph) } else { Vec::new() } +} + fn too_deep_on_top() -> EditError { EditError::Invalid("the page's marked content is nested too deeply to add anything on top of it".into()) } diff --git a/crates/edit/src/tests.rs b/crates/edit/src/tests.rs index e78da842b8..cbea5c21d2 100644 --- a/crates/edit/src/tests.rs +++ b/crates/edit/src/tests.rs @@ -6213,6 +6213,126 @@ fn group_selection_refuses_incomplete_content_and_resource_budget_overruns() { assert!(editable_objects(&doc, 0).is_err(), "an undecodable stream is refused"); } +/// Invisible text moves on top only when something painted after it covers it: an XObject drawn +/// over its box (an image, or a form holding one), or any inline image or shading. An image +/// clipped away entirely, or drawn elsewhere, does not move it. +#[test] +fn revealed_text_moves_on_top_only_when_painted_over() { + let on_top_of = |doc: Document| { + let block = text::text_blocks(&doc, 0).unwrap().remove(0); + let ops = pdfcraft_content::parse(&page_content_bytes(&doc, 0)).ops; + let at = ops.iter().position(|o| o.is("BT")).unwrap(); + revealed_under_paint(&doc, 0, block.invisible, block.rect, &ops, at) + }; + let on_top = |content: &str| on_top_of(image_page_with(content)); + let scan = "q 200 0 0 100 100 100 cm /Im0 Do Q"; + assert!(on_top(&format!("BT /F1 12 Tf 3 Tr 110 150 Td (Under) Tj ET {scan}")), "the scan covers it"); + assert!(!on_top(&format!("BT /F1 12 Tf 3 Tr 400 600 Td (Away) Tj ET {scan}")), "an image elsewhere"); + assert!(!on_top(&format!("{scan} BT /F1 12 Tf 3 Tr 110 150 Td (Over) Tj ET")), "the scan is drawn first"); + assert!(!on_top(&format!("BT /F1 12 Tf 0 Tr 110 150 Td (Shown) Tj ET {scan}")), "visible text stays where it is"); + assert!(!on_top("BT /F1 12 Tf 3 Tr 110 150 Td (Path) Tj ET 0 0 600 800 re f"), "a filled path does not move it"); + assert!(on_top("BT /F1 12 Tf 3 Tr 400 600 Td (Shade) Tj ET /Sh sh"), "a shading after it"); + assert!(on_top("BT /F1 12 Tf 3 Tr 400 600 Td (Inline) Tj ET BI /W 1 /H 1 /CS /G /BPC 8 ID x EI"), "an inline image after it"); + let under = "BT /F1 12 Tf 3 Tr 110 150 Td (Under) Tj ET"; + let elsewhere = "q 50 0 0 50 400 600 cm /Im0 Do Q"; + assert!(!on_top(&format!("{under} q 0 0 10 10 re W n {scan} Q")), "the scan is clipped away entirely"); + assert!(on_top(&format!("{under} {elsewhere} {scan}")), "two images, the second over it"); + assert!(on_top(&format!("{under} {scan} {elsewhere}")), "two images, the first over it"); + assert!(!on_top(&format!("{under} {elsewhere} {elsewhere}")), "two images, neither over it"); + let in_form = |content: &str| { + let page = "<< /Type /Page /Parent 2 0 R /MediaBox [0 0 600 800] /Contents 4 0 R /Resources << /Font << /F1 5 0 R >> /XObject << /Fm0 7 0 R >> >> >>"; + let image = stream("/Type /XObject /Subtype /Image /Width 1 /Height 1 /ColorSpace /DeviceGray /BitsPerComponent 8", "A"); + let form = stream("/Type /XObject /Subtype /Form /BBox [0 0 1 1] /Resources << /XObject << /Im0 6 0 R >> >>", "/Im0 Do"); + let objs = [ + "<< /Type /Catalog /Pages 2 0 R >>".to_string(), + "<< /Type /Pages /Kids [3 0 R] /Count 1 >>".into(), + page.into(), + stream("", content), + "<< /Type /Font /Subtype /Type1 /BaseFont /Helvetica >>".into(), + image, + form, + ]; + on_top_of(build(&objs.iter().map(String::as_str).collect::>())) + }; + assert!(in_form(&format!("{under} q 200 0 0 100 100 100 cm /Fm0 Do Q")), "a form holding the scan, over it"); + assert!(!in_form(&format!("{under} q 50 0 0 50 400 600 cm /Fm0 Do Q")), "a form holding an image elsewhere"); +} + +/// Revealed OCR text is checked where the rewrite lands, not only where it was: an image drawn +/// after it over just the moved or grown text still lifts the text on top, on both rewrite paths. +#[test] +fn an_ocr_rewrite_goes_on_top_of_paint_over_where_it_lands() { + let scan = "q 200 0 0 100 100 100 cm /Im0 Do Q"; + let moved = text::BlockStyle { offset: Some([-290.0, -450.0]), ..Default::default() }; + let sized = text::BlockStyle { size: Some(24.0), ..Default::default() }; + let spaced = text::BlockStyle { line_spacing: Some(3.0), ..Default::default() }; + let range = text::RangeStyle { + range: 0..2, + family: None, + resource: None, + size: Some(120.0), + color: None, + underline: None, + char_spacing: None, + scale: None, + }; + let enlarged = text::BlockStyle { ranges: vec![range], ..Default::default() }; + let above = "q 200 0 0 60 100 200 cm /Im0 Do Q"; + let cases = [ + ("BT /F1 12 Tf 3 Tr 400 600 Td (Away) Tj ET", "Moved", &moved), + ("BT /F1 12 Tf 3 Tr 400 600 Td (Away) Tj ET", "Moved\nTwice", &moved), + ("BT /F1 12 Tf 3 Tr 40 150 Td (Hi) Tj ET", "Hello there, this line now runs well past the scan's left edge", &text::BlockStyle::default()), + ("BT /F1 12 Tf 3 Tr 40 150 Td (Hi) Tj ET", "Hello there,\nthis line now runs well past the scan's left edge", &text::BlockStyle::default()), + ("BT /F1 12 Tf 3 Tr 110 230 Td (Above) Tj ET", "One\nTwo\nThree\nFour\nFive\nSix", &text::BlockStyle::default()), + ]; + let low = "q 200 0 0 30 100 300 cm /Im0 Do Q"; + let cases = cases.into_iter().map(|(c, e, s)| (c, e, s, scan)).chain([ + ("BT /F1 12 Tf 3 Tr 110 500 Td (Above) Tj ET", "One\nTwo\nThree\nFour\nFive\nSix", &sized, low), + ("BT /F1 12 Tf 3 Tr 110 500 Td (Above) Tj ET", "One\nTwo\nThree\nFour\nFive\nSix", &spaced, low), + ("BT /F1 12 Tf 3 Tr 110 150 Td (Hi there) Tj ET", "Hi there", &enlarged, above), + ]); + for (content, edit, style, scan) in cases { + let mut doc = image_page_with(&format!("{content} {scan}")); + let before = text::text_blocks(&doc, 0).unwrap().remove(0); + let ops = pdfcraft_content::parse(&page_content_bytes(&doc, 0)).ops; + let at = ops.iter().position(|o| o.is("BT")).unwrap(); + assert!(!revealed_under_paint(&doc, 0, true, before.rect, &ops, at), "{edit:?}: the old box alone is clear of the scan"); + text::rewrite_block(&mut doc, 0, 0, Some(edit), style).unwrap(); + let ops = pdfcraft_content::parse(&page_content_bytes(&doc, 0)).ops; + let scan_at = ops.iter().position(|o| o.is("Do")).unwrap(); + let shows = ["Tj", "TJ", "'", "\""]; + assert!(ops.iter().skip(scan_at).any(|o| shows.iter().any(|s| o.is(s))), "{edit:?}: the rewrite is drawn over the scan"); + } +} + +/// [`crate::Reach`] grows the old box to the move, the width either way and the lines below. +#[test] +fn a_rewrites_reach_covers_its_move_width_and_lines() { + let reach = |offset, width, rows, upright| crate::Reach { rect: [10.0, 90.0, 30.0, 100.0], offset, width, rows, pitch: 10.0, upright }.bounds(); + assert_eq!(reach([0.0, 0.0], 20.0, 1, true), [10.0, 90.0, 30.0, 110.0]); + assert_eq!(reach([5.0, -50.0], 20.0, 1, true), [10.0, 40.0, 35.0, 100.0]); + assert_eq!(reach([0.0, 0.0], 50.0, 3, true), [-20.0, 70.0, 60.0, 110.0]); + assert_eq!(reach([0.0, 0.0], 30.0, 4, false), [-40.0, 40.0, 80.0, 150.0]); + assert_eq!(reach([f64::NAN, 0.0], 20.0, 1, true)[0], f64::NEG_INFINITY); + let larger = crate::Reach { rect: [10.0, 90.0, 30.0, 100.0], offset: [0.0, 0.0], width: 20.0, rows: 1, pitch: 24.0, upright: true }; + assert_eq!(larger.bounds(), [10.0, 76.0, 30.0, 124.0], "a larger size grows the line up as well as down"); +} + +/// Revealed OCR text may have to go on top of the page; a page whose marked content nests too deep +/// for that is refused before either rewrite path changes anything. +#[test] +fn an_ocr_rewrite_refused_on_top_leaves_the_document_as_it_was() { + let content = format!("{} BT /F1 20 Tf 3 Tr 42 44 Td (John) Tj ET /Im Do {}", "/X BMC ".repeat(10_001), "EMC ".repeat(10_001)); + let mut doc = text_page(&content); + assert!(text::text_blocks(&doc, 0).unwrap()[0].invisible); + let before = write_full(&doc, &SaveOptions::default()).unwrap(); + for edit in ["Jane", "Jane\nDoe"] { + let error = text::rewrite_block(&mut doc, 0, 0, Some(edit), &text::BlockStyle::default()).unwrap_err(); + assert!(error.to_string().contains("nested too deeply"), "{edit:?}: {error}"); + assert!(write_full(&doc, &SaveOptions::default()).unwrap() == before, "{edit:?}: a refused rewrite changes nothing"); + } +} + #[test] fn group_move_budget_refusals_keep_the_original_page_selectable() { let text = text_page(&format!("{} BT /F1 12 Tf 40 400 Td (Target) Tj ET", "n ".repeat(99_995))); diff --git a/crates/edit/src/text/blocks.rs b/crates/edit/src/text/blocks.rs index 9ddf4db4b1..48fe956f4f 100644 --- a/crates/edit/src/text/blocks.rs +++ b/crates/edit/src/text/blocks.rs @@ -31,7 +31,8 @@ pub struct TextBlock { /// Byte ranges in `editor_text` and their source line indexes. pub spans: Vec<(std::ops::Range, usize)>, /// Every line is invisible text (rendering mode 3): an OCR layer over a scanned image, whose - /// pixels show the words. A rewrite draws the new text visibly (see [`BlockStyle::cover`]). + /// pixels show the words. A rewrite draws the new text visibly, on top of the page when + /// the scan is drawn after it (see [`BlockStyle::cover`]). pub invisible: bool, } diff --git a/crates/edit/src/text/interp.rs b/crates/edit/src/text/interp.rs index 2a9f6da61a..5114a76263 100644 --- a/crates/edit/src/text/interp.rs +++ b/crates/edit/src/text/interp.rs @@ -18,13 +18,33 @@ pub(super) struct TextState { /// graphics state the text was painted with that [`TextState::ops`] doesn't restate. pub(super) stroke: Vec, pub(super) line_width: Option, - ext_gstate: Vec>, + ext_gstate: Vec, /// The dash pattern and line cap in force (see [`Ts`]): compared, not restated. pub(super) dash: Dash, pub(super) line_cap: i64, } impl TextState { + /// The state a page's content starts in (ISO 32000-2 §8.4.1, §9.3.1): what is in force on + /// top of the page, after its content wrapped in `q`/`Q`. + pub(crate) fn initial() -> Self { + TextState { + font: None, + char_spacing: 0.0, + word_spacing: 0.0, + scale: 1.0, + leading: 0.0, + rise: 0.0, + fill: Vec::new(), + render_mode: 0, + stroke: Vec::new(), + line_width: None, + ext_gstate: Vec::new(), + dash: (Vec::new(), 0.0), + line_cap: 0, + } + } + pub(super) fn of(ts: &Ts) -> Self { TextState { font: ts.font.as_ref().map(|(n, _)| (String::from_utf8_lossy(n).into_owned(), ts.size)), @@ -54,13 +74,17 @@ impl TextState { /// /// A `gs` has no inverse, so a selection `current` has and this state doesn't stays in force: /// run these inside a `q`/`Q` that starts from `current`, one per state drawn. - pub(crate) fn paint_ops(&self, current: &TextState) -> Vec { + /// + /// `ctm` is the CTM where they run. A soft mask is placed by the CTM its `gs` ran at + /// (ISO 32000-2 §11.6.5.2), so one selected at another CTM is selected there and the CTM + /// set back. + pub(crate) fn paint_ops(&self, current: &TextState, ctm: [f64; 6]) -> Vec { let n = pdfcraft_content::num; let mut v = Vec::new(); // The selections both share stay in force; the ones after them are selected again in order. let shared = self.ext_gstate.iter().zip(¤t.ext_gstate).take_while(|(a, b)| a == b).count(); - for name in self.ext_gstate.iter().skip(shared) { - v.push(Op::new("gs", vec![Object::Name(name.clone())])); + for sel in self.ext_gstate.iter().skip(shared) { + sel.push_ops(&mut v, ctm); } // A reselected ExtGState may set `/LW`, so the width (already the effective one) follows it. let reselected = !v.is_empty(); @@ -222,7 +246,7 @@ pub(super) struct Ts { /// The line width a `w` or an ExtGState's `/LW` set (`None`: the initial 1.0). pub(super) line_width: Option, /// The ExtGState resources selected with `gs`, oldest first (see [`select_gs`]). - pub(super) ext_gstate: Vec>, + pub(super) ext_gstate: Vec, /// The dash pattern a `d` or an ExtGState's `/D` set (initially solid: `[] 0`). pub(super) dash: Dash, /// The line cap a `J` or an ExtGState's `/LC` set (initially 0, butt). @@ -255,12 +279,38 @@ const MAX_GS: usize = 32; /// Record `gs /name` in `list`. A `gs` sets every parameter its dictionary names to an absolute /// value, so a later selection of the same dictionary overrides the earlier one completely: the /// earlier entry goes, which keeps replaying the list equivalent to replaying the stream. -fn select_gs(list: &mut Vec>, name: &[u8]) { - list.retain(|n| n != name); +fn select_gs(list: &mut Vec, name: &[u8], anchor: Option<[f64; 6]>) { + list.retain(|s| s.name != name); if list.len() >= MAX_GS { list.remove(0); } - list.push(name.to_vec()); + list.push(GsSelection { name: name.to_vec(), anchor }); +} + +/// One `gs` selection: the ExtGState's resource name, and the CTM it ran at when the dictionary +/// has a soft mask, which that CTM places (ISO 32000-2 §11.6.5.2). +#[derive(Clone, Debug, PartialEq)] +pub(crate) struct GsSelection { + name: Vec, + anchor: Option<[f64; 6]>, +} + +impl GsSelection { + /// Select this ExtGState from where the CTM is `ctm`: at its anchor, then back to `ctm`. Both + /// moves need an invertible matrix; without one it is selected where it runs. + fn push_ops(&self, v: &mut Vec, ctm: [f64; 6]) { + let gs = Op::new("gs", vec![Object::Name(self.name.clone())]); + let moves = self.anchor.filter(|a| *a != ctm).and_then(|a| { + let (anchor, here) = (Matrix(a), Matrix(ctm)); + Some((anchor.then(&here.invert()?), here.then(&anchor.invert()?))) + }); + let Some((to, back)) = moves else { + v.push(gs); + return; + }; + let cm = |m: Matrix| Op::new("cm", m.0.iter().map(|x| pdfcraft_content::num(*x)).collect()); + v.extend([cm(to), gs, cm(back)]); + } } /// The text-showing operators of one stream with their text, font, box and baseline. @@ -879,14 +929,15 @@ pub(super) fn interpret( b"Ts" => ts.rise = op.num(0).unwrap_or(0.0), b"Tr" => ts.render_mode = op.operands.first().and_then(Object::as_int).unwrap_or(-1), b"gs" => { - if let Some(name) = op.name(0) { - select_gs(&mut ts.ext_gstate, name); - } let mut held = None; let params = match op.name(0).and_then(|name| states.get(name)) { Some(p) => super::dict_in_place(doc, p, &mut held), None => None, }; + if let Some(name) = op.name(0) { + let masked = params.and_then(|p| p.get(b"SMask")).is_some_and(|m| doc.resolve(m).as_dict().is_some()); + select_gs(&mut ts.ext_gstate, name, masked.then_some(ts.ctm.0)); + } if let Some(params) = params { ts.gs.apply(doc, params); // `/LW` sets the line width as `w` does (ISO 32000-2 §8.4.5). diff --git a/crates/edit/src/text/rewrite.rs b/crates/edit/src/text/rewrite.rs index ec2fac984c..d27d23e0b5 100644 --- a/crates/edit/src/text/rewrite.rs +++ b/crates/edit/src/text/rewrite.rs @@ -702,11 +702,13 @@ fn block_ops(plan: &BlockPlan<'_>, writer: &LineWriter<'_>, wrapped: &[(String, let mut ops = vec![Op::new("q", vec![])]; ops.extend(reveal_ops(plan.block, plan.lines, plan.style, plan.emit.ctm)?); // Moved: a translation inside that state. + let mut ctm = Matrix(plan.emit.ctm); if let Some((ax, ay)) = plan.movement { ops.push(Op::new("cm", vec![n(1.0), n(0.0), n(0.0), n(1.0), n(ax), n(ay)])); + ctm = Matrix([1.0, 0.0, 0.0, 1.0, ax, ay]).then(&ctm); } // Painted as the paragraph was, including what its text object set before the first show. - ops.extend(plan.state.paint_ops(plan.after)); + ops.extend(plan.state.paint_ops(plan.after, ctm.0)); ops.push(Op::new("BT", vec![])); let mut state = plan.state.clone(); state.word_spacing = 0.0; @@ -816,6 +818,11 @@ pub(crate) fn rewrite_block_from( let first = members.first().copied().ok_or_else(|| EditError::Invalid("the paragraph has no source runs".into()))?; members.iter().try_for_each(|line| line.ensure_editable())?; let p = page_dict(doc, page)?; + // Revealed OCR text may go on top of the page (see `revealed_under_paint`): a page that can't + // take that is refused here, before either rewrite path changes anything. + if b.invisible { + crate::check_on_top(doc, &p)?; + } let mut res = p.dict.get(b"Resources").map(|r| doc.resolve(r)).and_then(|r| r.as_dict().cloned()).unwrap_or_default(); let mut fonts_res = res.get(b"Font").map(|f| doc.resolve(f)).and_then(|f| f.as_dict().cloned()).unwrap_or_default(); let dispatch = choose_rewrite_path(doc, &fonts_res, &b, &members, first, text, style)?; @@ -930,9 +937,28 @@ pub(crate) fn rewrite_block_from( char_spacing: o_state.char_spacing, lead, }; - let plan = - BlockPlan { block: &b, lines: &lines, style, emit, after, movement, state: o_state, tm, size, underline: style.underline == Some(true) }; + let at = if split { start } else { emit.bt_op }; + // Revealed OCR text that something is painted over goes on top of the page, where it starts + // from the initial state. + let widest = wrapped.iter().map(|(l, _, _)| advance.of(l)).fold(width, f64::max); + let reach = crate::Reach { rect: b.rect, offset: [dx, dy], width: widest, rows: wrapped.len(), pitch: lead * k, upright }; + let over = crate::revealed_under_paint(doc, page, b.invisible, reach.bounds(), &ops, at); + let initial = TextState::initial(); + let drawn_from = if over { &initial } else { after }; + let plan = BlockPlan { + block: &b, + lines: &lines, + style, + emit, + after: drawn_from, + movement, + state: o_state, + tm, + size, + underline: style.underline == Some(true), + }; let mut block_ops = block_ops(&plan, &writer, &wrapped, font.show_font.clone())?; + let on_top = crate::lift_on_top(over, &mut block_ops); let n = pdfcraft_content::num; block_ops.extend(after.ops().into_iter().filter(|op| !op.is("Tf") || after.font.is_some())); if split { @@ -940,7 +966,6 @@ pub(crate) fn rewrite_block_from( block_ops.push(Op::new("BT", vec![])); block_ops.push(Op::new("Tm", emit.tlm.iter().map(|v| n(*v)).collect())); } - let at = if split { start } else { emit.bt_op }; let new_data = splice(&pieces, &ops, |i| { let insert = if i == at { std::mem::take(&mut block_ops) } else { Vec::new() }; (insert, !dropped.contains(&i)) @@ -957,12 +982,14 @@ pub(crate) fn rewrite_block_from( d.set(b"Resources".to_vec(), Object::Dict(res)); } })?; + crate::draw_on_top(doc, &p, emit.ctm, &on_top)?; Ok(LineEdit { substituted: font.substituted }) } /// The cover (when [`BlockStyle::cover`] asks for one) and visible rendering that start a /// rewritten invisible paragraph, drawn in the space whose CTM is `ctm`. Nothing for visible text. -/// The paragraph's `q`/`Q` restores the rendering mode for the invisible text after it. +/// The paragraph's `q`/`Q` restores the rendering mode for the invisible text after it; one +/// painted over where it was is drawn on top of the page instead ([`crate::draw_on_top`]). pub(crate) fn reveal_ops(block: &TextBlock, lines: &[TextLine], style: &BlockStyle, ctm: [f64; 6]) -> Result, EditError> { if !block.invisible { return Ok(Vec::new()); diff --git a/crates/edit/src/text_regions/styled.rs b/crates/edit/src/text_regions/styled.rs index 885a0a7158..7a9204a8c0 100644 --- a/crates/edit/src/text_regions/styled.rs +++ b/crates/edit/src/text_regions/styled.rs @@ -1,3 +1,4 @@ +use super::super::interp::TextState; use super::grouping::{across, is_centred, row_rect}; use super::{ BlockStyle, CraftFont, Dict, Document, EditError, HashMap, LineEdit, MAX_TYPE3_GLYPHS, Matrix, Metrics, Object, Op, PdfString, Pieces, @@ -401,6 +402,16 @@ fn paragraph_geometry(doc: &Document, page: &pdfcraft_model::Page, block: &TextB Ok((dx, dy, style.width.unwrap_or(natural).clamp(1.0, 14_400.0))) } +/// How far below a row of `size` the next one is written: the source's leading unless a size +/// or line spacing is chosen. +fn row_step(style: &BlockStyle, size: f64, source_leading: f64) -> f64 { + if style.line_spacing.is_none() && style.size.is_none() { + source_leading + } else { + style.line_spacing.unwrap_or(1.5).clamp(0.5, 5.0) * style.size.unwrap_or(size) + } +} + type WrappedStyledRows = (StyledRows, RowRanges, Vec, Vec, Vec); fn wrap_styled_rows( @@ -976,6 +987,7 @@ pub(crate) fn rewrite_styled_block( let o = &lead.origin; // What is in force where the rewrite is drawn, and what the text after it expects. let after = if split { &o.state } else { &o.bt_state }; + let at = if split { start } else { o.bt_op }; validate_contextual_rows(&rows, &kept)?; let measured: Vec<_> = rows.iter().map(|row| measure(row)).collect::>()?; let shaped = prepare_shaped_rows(doc, &fonts, &rows, &kept, advance)?; @@ -989,6 +1001,7 @@ pub(crate) fn rewrite_styled_block( .ok_or_else(|| EditError::Invalid("the paragraph is drawn in a space it cannot be edited in".into()))?; let (tx, ty) = back.apply(dx, dy); block_ops.push(Op::new("cm", vec![n(1.0), n(0.0), n(0.0), n(1.0), n(tx), n(ty)])); + let run_ctm = Matrix([1.0, 0.0, 0.0, 1.0, tx, ty]).then(&Matrix(o.ctm)).0; // A new row can land one leading above the next paragraph and look like the same // paragraph. When every row is in this rewrite, a paragraph marker keeps them in one // scope so the neighbour stays out (#2517). A row left in the source stream cannot share @@ -1007,6 +1020,19 @@ pub(crate) fn rewrite_styled_block( }) .rfind(|v| *v > 0.0) .unwrap_or(first.size * 1.5); + // Revealed OCR text that something is painted over goes on top of the page, where it starts + // from the initial state. + let largest = + block.lines.iter().filter_map(|i| lines.get(*i)).map(|l| l.size).chain(style.ranges.iter().filter_map(|r| r.size)).fold(first.size, f64::max); + // At least one line of the largest glyphs, so a larger range reaches up as far as it draws. + const LINE_EM: f64 = 1.2; + let pitch = source_leading.max(row_step(style, largest, source_leading)).max(largest * LINE_EM); + let widest = measured.iter().copied().fold(width, f64::max); + // This path lays rows out along user-space baselines, so the paragraph is upright here. + let reach = crate::Reach { rect: block.rect, offset: [dx, dy], width: widest, rows: rows.len(), pitch, upright: true }; + let over = crate::revealed_under_paint(doc, page, block.invisible, reach.bounds(), &ops, at); + let initial = TextState::initial(); + let drawn_from = if over { &initial } else { after }; let mut baseline = first.origin.baseline; for (row_index, row) in rows.iter().enumerate() { let anchor = block.rows.get(row_index).and_then(|r| r.first()).and_then(|i| lines.get(*i)); @@ -1073,7 +1099,7 @@ pub(crate) fn rewrite_styled_block( // object (`gs`, stroke, line width, `Tr`; #3508/#3509) from the state the rewrite is // drawn in: a `gs` has no inverse, so one run's ExtGState would stay for the next. block_ops.push(Op::new("q", vec![])); - block_ops.extend(state.paint_ops(after)); + block_ops.extend(state.paint_ops(drawn_from, run_ctm)); if let Some((_, shaped, _)) = shaped_runs.get(&(row_index, pos)) { let resource = glyph_resources.get(&(row_index, pos)).ok_or_else(|| EditError::Invalid("shaped font is missing".into()))?; let mut properties = Dict::new(); @@ -1164,21 +1190,17 @@ pub(crate) fn rewrite_styled_block( x += segment_width; pos = end; } - baseline -= if style.line_spacing.is_none() && style.size.is_none() { - source_leading - } else { - style.line_spacing.unwrap_or(1.5).clamp(0.5, 5.0) * style.size.unwrap_or(anchor.size) - }; + baseline -= row_step(style, anchor.size, source_leading); } push_whole_paragraph_marker(&mut block_ops, marked, "EMC"); block_ops.push(Op::new("Q", vec![])); + let on_top = crate::lift_on_top(over, &mut block_ops); block_ops.extend(after.ops()); if split { block_ops.insert(0, Op::new("ET", vec![])); block_ops.push(Op::new("BT", vec![])); block_ops.push(Op::new("Tm", o.tlm.iter().map(|v| n(*v)).collect())); } - let at = if split { start } else { o.bt_op }; // A kept source row sits outside `block_ops`. Bound the whole paragraph when a marker is // safe. The close is not part of `block_ops`: that vector can end inside a text object // when the rewrite splits one, and a kept row's operators come later in the stream. @@ -1190,5 +1212,6 @@ pub(crate) fn rewrite_styled_block( d.set(b"Contents".to_vec(), contents); d.set(b"Resources".to_vec(), Object::Dict(res)); })?; + crate::draw_on_top(doc, &p, o.ctm, &on_top)?; Ok(LineEdit { substituted }) } diff --git a/crates/engine/tests/it/ocr_edit.rs b/crates/engine/tests/it/ocr_edit.rs index 8009ef1bbf..53ca309326 100644 --- a/crates/engine/tests/it/ocr_edit.rs +++ b/crates/engine/tests/it/ocr_edit.rs @@ -207,3 +207,192 @@ fn visible_stretched_text_rewrites_unchanged() { let i = ((y * out.width + x) * 4) as usize; assert_eq!(&out.rgba[i..i + 3], &[255, 255, 255]); } + +/// A scan whose OCR layer is drawn first and the opaque page image over it, as some OCR tools +/// write it (#3973): invisible Helvetica `text` on the scanned word, then the image. +fn ocr_under_scan(text: &str) -> std::sync::Arc> { + under_scan(&format!("BT /F1 20 Tf 3 Tr 42 44 Td ({text}) Tj ET")) +} + +/// A page whose `text` content is followed by the opaque 200 × 100 scan image. +fn under_scan(text: &str) -> std::sync::Arc> { + under_scan_with(text, |_| pdfcraft_cos::Dict::new()) +} + +/// As [`under_scan`], with the page's ExtGState resources made by `ext_gstates`. +fn under_scan_with(text: &str, ext_gstates: impl FnOnce(&mut pdfcraft_cos::Document) -> pdfcraft_cos::Dict) -> std::sync::Arc> { + use pdfcraft_cos::{Dict, Document, Object, SaveOptions, Stream}; + let (w, h) = (200u32, 100u32); + let mut rgb = Vec::new(); + for y in 0..h { + for x in 0..w { + let ink = (WORD[0]..WORD[2]).contains(&x) && (WORD[1]..WORD[3]).contains(&y); + rgb.extend(if ink { INK } else { PAPER }); + } + } + let mut d = Document::new_empty(); + let pages = d.add(Object::Dict(Dict::new())); + let content = format!("{text} q 200 0 0 100 0 0 cm /Im Do Q"); + let contents = d.add(Object::Stream(Stream::flate(Dict::new(), content.as_bytes()))); + let mut image = Dict::new(); + image.set(b"Type".to_vec(), Object::name("XObject")); + image.set(b"Subtype".to_vec(), Object::name("Image")); + image.set(b"Width".to_vec(), Object::Int(i64::from(w))); + image.set(b"Height".to_vec(), Object::Int(i64::from(h))); + image.set(b"ColorSpace".to_vec(), Object::name("DeviceRGB")); + image.set(b"BitsPerComponent".to_vec(), Object::Int(8)); + let image = d.add(Object::Stream(Stream::flate(image, &rgb))); + let mut font = Dict::new(); + font.set(b"Type".to_vec(), Object::name("Font")); + font.set(b"Subtype".to_vec(), Object::name("Type1")); + font.set(b"BaseFont".to_vec(), Object::name("Helvetica")); + let mut fonts = Dict::new(); + fonts.set(b"F1".to_vec(), Object::Dict(font)); + let mut xobjects = Dict::new(); + xobjects.set(b"Im".to_vec(), Object::Ref(image)); + let mut res = Dict::new(); + res.set(b"Font".to_vec(), Object::Dict(fonts)); + res.set(b"XObject".to_vec(), Object::Dict(xobjects)); + res.set(b"ExtGState".to_vec(), Object::Dict(ext_gstates(&mut d))); + let mut p = Dict::new(); + p.set(b"Type".to_vec(), Object::name("Page")); + p.set(b"Parent".to_vec(), Object::Ref(pages)); + p.set(b"Contents".to_vec(), Object::Ref(contents)); + p.set(b"Resources".to_vec(), Object::Dict(res)); + p.set(b"MediaBox".to_vec(), Object::Array([0, 0, 200, 100].map(Object::Int).to_vec())); + let page = d.add(Object::Dict(p)); + d.update_dict(pages, |p| { + p.set(b"Type".to_vec(), Object::name("Pages")); + p.set(b"Kids".to_vec(), Object::Array(vec![Object::Ref(page)])); + p.set(b"Count".to_vec(), Object::Int(1)); + }) + .unwrap(); + let mut root = Dict::new(); + root.set(b"Type".to_vec(), Object::name("Catalog")); + root.set(b"Pages".to_vec(), Object::Ref(pages)); + let root = d.add(Object::Dict(root)); + d.trailer_mut().set(b"Root".to_vec(), Object::Ref(root)); + std::sync::Arc::new(pdfcraft_cos::write_full(&d, &SaveOptions::default()).unwrap()) +} + +/// The scanned word's box shows the cover and new ink, not the scan. +fn assert_edit_shows(s: &Session, id: pdfcraft_engine::DocId, label: &str) { + let px = word_pixels(s, id); + let paper = px.iter().filter(|p| near(**p, PAPER)).count(); + let ink = px.iter().filter(|p| near(**p, INK)).count(); + assert!(paper * 10 > px.len() * 4, "{label}: the cover is drawn over the scan: {paper} of {} paper", px.len()); + assert!(ink * 100 > px.len() * 3, "{label}: the new text shows: {ink} of {} ink", px.len()); +} + +fn texts(s: &Session, id: pdfcraft_engine::DocId) -> Vec { + s.get(id).unwrap().text_blocks(0).iter().map(|b| b.text.replace('\n', " ")).collect() +} + +fn edit_block(s: &mut Session, id: pdfcraft_engine::DocId, block: usize, text: &str) { + s.apply(id, Edit::EditTextBlock { page: 0, block, text: text.into(), style: Default::default() }).unwrap(); +} + +/// The OCR layer is under the scan image: the rewritten paragraph is drawn on top of the image, +/// not in the OCR text's place where the image would hide it (#3973). One line takes the +/// single-style rewrite, a typed line break the styled one. Undo restores the hidden layer, and +/// the edit survives redo, a save and reopen, and being edited again. +#[test] +fn an_ocr_layer_under_the_scan_image_shows_its_edit() { + for edit in ["Jane", "Jane\nDoe"] { + let mut s = Session::new(); + let id = s.open("ocr-under-scan.pdf", None, ocr_under_scan("John"), None).unwrap(); + let blocks = s.get(id).unwrap().text_blocks(0); + assert_eq!(blocks.len(), 1); + assert!(blocks[0].invisible, "the OCR layer is invisible text"); + assert!(word_pixels(&s, id).iter().all(|p| near(*p, INK)), "the scanned word fills its box"); + + edit_block(&mut s, id, 0, edit); + assert_eq!(texts(&s, id), [edit.replace('\n', " ")], "{edit:?}"); + assert_edit_shows(&s, id, edit); + + s.undo(id).unwrap(); + assert_eq!(texts(&s, id), ["John"], "{edit:?}: undo"); + assert!(s.get(id).unwrap().text_blocks(0)[0].invisible, "{edit:?}: undo hides the layer again"); + assert!(word_pixels(&s, id).iter().all(|p| near(*p, INK)), "{edit:?}: undo shows the scan again"); + s.redo(id).unwrap(); + assert_edit_shows(&s, id, &format!("{edit:?} redo")); + + let saved = s.save_bytes(id).unwrap(); + let mut reopened = Session::new(); + let id = reopened.open("saved.pdf", None, saved, None).unwrap(); + assert_eq!(texts(&reopened, id), [edit.replace('\n', " ")], "{edit:?}: reopened"); + assert_edit_shows(&reopened, id, &format!("{edit:?} reopened")); + + edit_block(&mut reopened, id, 0, "Ann"); + assert_eq!(texts(&reopened, id), ["Ann"], "{edit:?}: edited again"); + assert_edit_shows(&reopened, id, &format!("{edit:?} edited again")); + } +} + +/// Visible text earlier in the same text object makes the rewrite split it; the OCR phrase still +/// goes on top of the scan, and the visible text stays. +#[test] +fn an_ocr_phrase_split_from_visible_text_under_the_scan_shows_its_edit() { + for edit in ["Jane", "Jane\nDoe"] { + let mut s = Session::new(); + let page = under_scan("BT /F1 20 Tf 10 80 Td (Head) Tj 3 Tr 32 -36 Td (John) Tj ET"); + let id = s.open("split.pdf", None, page, None).unwrap(); + let blocks = s.get(id).unwrap().text_blocks(0); + let john = blocks.iter().position(|b| b.text == "John").unwrap(); + assert!(blocks[john].invisible && blocks.iter().any(|b| b.text == "Head" && !b.invisible), "{blocks:?}"); + edit_block(&mut s, id, john, edit); + let mut after = texts(&s, id); + after.sort(); + let mut want = vec!["Head".to_string(), edit.replace('\n', " ")]; + want.sort(); + assert_eq!(after, want, "{edit:?}"); + assert_edit_shows(&s, id, &format!("{edit:?} split")); + } +} + +/// `/SM`: a luminosity soft mask that is white over 30..110 × 30..70 in the space it is selected +/// in, black elsewhere. +fn soft_mask_state(d: &mut pdfcraft_cos::Document) -> pdfcraft_cos::Dict { + use pdfcraft_cos::{Dict, Object, Stream}; + let mut group = Dict::new(); + group.set(b"S".to_vec(), Object::name("Transparency")); + group.set(b"CS".to_vec(), Object::name("DeviceRGB")); + let mut form = Dict::new(); + form.set(b"Type".to_vec(), Object::name("XObject")); + form.set(b"Subtype".to_vec(), Object::name("Form")); + form.set(b"BBox".to_vec(), Object::Array([0, 0, 200, 100].map(Object::Int).to_vec())); + form.set(b"Group".to_vec(), Object::Dict(group)); + let mut mask = Dict::new(); + mask.set(b"Type".to_vec(), Object::name("Mask")); + mask.set(b"S".to_vec(), Object::name("Luminosity")); + mask.set(b"G".to_vec(), Object::Ref(d.add(Object::Stream(Stream::flate(form, b"1 g 30 30 80 40 re f"))))); + let mut state = Dict::new(); + state.set(b"Type".to_vec(), Object::name("ExtGState")); + state.set(b"SMask".to_vec(), Object::Dict(mask)); + let mut states = Dict::new(); + states.set(b"SM".to_vec(), Object::Dict(state)); + states +} + +/// The soft mask is selected before a translation, so it is placed by the CTM before it. The +/// paragraph lifted over the scan selects it again after its own `cm`: there it must be placed +/// as it was, not 100 pt to the right where it would hide the new text, so the edit renders +/// exactly as the same edit on the page without the mask. Both rewrite paths. +#[test] +fn a_soft_mask_selected_before_a_cm_stays_put_when_the_edit_is_lifted() { + for edit in ["Jane", "Jane\nDoe"] { + let mut plain = Session::new(); + let page = under_scan("q 1 0 0 1 100 0 cm BT /F1 20 Tf 3 Tr -58 44 Td (John) Tj ET Q"); + let plain_id = plain.open("plain.pdf", None, page, None).unwrap(); + edit_block(&mut plain, plain_id, 0, edit); + let mut s = Session::new(); + let page = under_scan_with("q /SM gs 1 0 0 1 100 0 cm BT /F1 20 Tf 3 Tr -58 44 Td (John) Tj ET Q", soft_mask_state); + let id = s.open("masked.pdf", None, page, None).unwrap(); + assert_eq!(texts(&s, id), ["John"]); + edit_block(&mut s, id, 0, edit); + assert_eq!(texts(&s, id), [edit.replace('\n', " ")], "{edit:?}"); + assert_edit_shows(&s, id, &format!("{edit:?} masked")); + let ink = |s: &Session, id| word_pixels(s, id).iter().filter(|p| near(**p, INK)).count(); + assert_eq!(ink(&s, id), ink(&plain, plain_id), "{edit:?}: the mask does not hide the new text"); + } +} diff --git a/parity/acrobat-features.toml b/parity/acrobat-features.toml index 7011cd5644..27f9c35e0d 100644 --- a/parity/acrobat-features.toml +++ b/parity/acrobat-features.toml @@ -6695,8 +6695,8 @@ milestone = "M10" status = "partial" commands = ["edit.edit_text"] tools = ["text_edit"] -evidence = ["crates/engine/tests/it/ocr_edit.rs::editing_an_ocr_word_covers_the_scan_and_shows_the_new_text", "crates/engine/tests/it/ocr_edit.rs::an_explicit_colour_is_kept_for_the_new_text", "crates/engine/tests/it/ocr_edit.rs::ocr_words_group_into_phrases_that_edit_in_place", "crates/engine/tests/it/ocr_edit.rs::a_longer_ocr_phrase_grows_rightwards", "crates/engine/tests/it/ocr_edit.rs::a_rewritten_ocr_phrase_keeps_its_word_widths", "crates/ui-egui/tests/it/ocr.rs::an_ocr_word_opens_for_editing_and_stays_open", "crates/ui-egui/tests/it/ocr.rs::editing_a_scanned_page_recognizes_its_text_first_and_only_once"] -notes = "On demand, per edit: in Edit text & images, recognised text (the invisible OCR layer over a scan) is grouped into phrases (words across a word space; a wider gap such as a table cell, and each scanned line, stay separate) and opens for editing on a click. Applying draws the new text visibly in the scan's sampled ink colour (or the chosen one) and first covers the old words with the paper colour sampled around them, so the scanned word no longer shows; the phrase keeps each word's position and width and grows rightwards instead of wrapping. Turning Edit text & images on for a scanned page (an image covering at least half of a page that has no text of its own, once per page per window; comments and text boxes over it do not count as text, a page with real text and a background picture is left alone; one undoable \"Recognize text\" step) now recognizes its words first, as Acrobat's \"Converting scanned page to Editable Text and Images\" does (English only until more OCR languages exist, gap 7). Still missing: separating the photographs on the page from the lettering, matching the scanned typeface (the layer's Helvetica is used), and covering on a textured or patterned background (one flat colour is used)." +evidence = ["crates/engine/tests/it/ocr_edit.rs::editing_an_ocr_word_covers_the_scan_and_shows_the_new_text", "crates/engine/tests/it/ocr_edit.rs::an_explicit_colour_is_kept_for_the_new_text", "crates/engine/tests/it/ocr_edit.rs::ocr_words_group_into_phrases_that_edit_in_place", "crates/engine/tests/it/ocr_edit.rs::a_longer_ocr_phrase_grows_rightwards", "crates/engine/tests/it/ocr_edit.rs::a_rewritten_ocr_phrase_keeps_its_word_widths", "crates/engine/tests/it/ocr_edit.rs::an_ocr_layer_under_the_scan_image_shows_its_edit", "crates/engine/tests/it/ocr_edit.rs::an_ocr_phrase_split_from_visible_text_under_the_scan_shows_its_edit", "crates/ui-egui/tests/it/ocr.rs::an_ocr_word_opens_for_editing_and_stays_open", "crates/ui-egui/tests/it/ocr.rs::editing_a_scanned_page_recognizes_its_text_first_and_only_once"] +notes = "On demand, per edit: in Edit text & images, recognised text (the invisible OCR layer over a scan) is grouped into phrases (words across a word space; a wider gap such as a table cell, and each scanned line, stay separate) and opens for editing on a click. Applying draws the new text visibly in the scan's sampled ink colour (or the chosen one) and first covers the old words with the paper colour sampled around them, so the scanned word no longer shows; when an image or form is drawn after the OCR layer over where the edit lands (its old box, moved, rewrapped or grown to more lines), or an inline image or shading after it (a layer written under its scan, #3973), the cover and new text are drawn on top of the page instead, so they show; the phrase keeps each word's position and width and grows rightwards instead of wrapping. Turning Edit text & images on for a scanned page (an image covering at least half of a page that has no text of its own, once per page per window; comments and text boxes over it do not count as text, a page with real text and a background picture is left alone; one undoable \"Recognize text\" step) now recognizes its words first, as Acrobat's \"Converting scanned page to Editable Text and Images\" does (English only until more OCR languages exist, gap 7). Still missing: separating the photographs on the page from the lettering, matching the scanned typeface (the layer's Helvetica is used), covering on a textured or patterned background (one flat colour is used), a scan painted by a pattern fill or a filled rectangle over a layer written under it, and, for text drawn on top, the clip, optional content and marked content (tags) that enclosed the OCR layer." [[feature]] id = "ocr.ocr-downsample"