fix(engine): charge only the constants a row copies, count insert attributes, saturate, resolve autoload paths absolute and fail on the selected file

crates/engine/src/cmd/blocks/extract.rs

@@ -19,6 +19,21 @@ const MAX_TABLE_ROWS: usize = 2000;
 const MAX_TABLE_COLS: usize = 200;
 /// Attribute columns kept at most.
 const MAX_TAGS: usize = 190;
+/// Attribute text one extraction may hold across all its references (each row owns a copy of its
+/// values, constants included). Far above any real schedule; an error, never a silent cut.
+const MAX_VALUE_BYTES: usize = 1 << 30;
+
+/// Add `add` bytes to `used`; an error past `limit`.
+fn charge(used: &mut usize, add: usize, limit: usize) -> Result<()> {
+    *used = used.saturating_add(add);
+    if *used > limit {
+        return Err(bad(
+            "dataextraction",
+            format!("the attribute text of the block references passes {} MiB; narrow `blocks`, `tags` or `handles`", limit >> 20),
+        ));
+    }
+    Ok(())
+}
 
 const PARAMS: &str = "{blocks?: \"A*,B\" (block names, wildcards, default *), tags?: attribute tags to include (wildcards, default *), handles? (default: the block references in model space and every layout), combine?: bool (default true: identical rows once, with a Count column; false: one row per reference with handle, layer, position and rotation), file?: path (.csv; .txt is tab-separated), at?: [x,y] (insert a table there), title?: table title} → {columns, rows, file?, table?}";
 
@@ -167,6 +182,8 @@ fn found(s: &Session, p: &Value, o: &Options) -> Result<Vec<Found>> {
     };
     let selected = selected_tags(&ents, d, o);
     let mut out = Vec::new();
+    let mut used = 0usize;
+    let mut const_sizes: HashMap<String, Vec<(String, usize)>> = HashMap::new();
     let mut consts: HashMap<String, Vec<(String, String)>> = HashMap::new();
     for e in &ents {
         let EntityKind::Insert(ins) = &e.kind else { continue };
@@ -175,18 +192,47 @@ fn found(s: &Session, p: &Value, o: &Options) -> Result<Vec<Found>> {
             continue;
         }
         let block = d.block(&ins.block).map(|b| b.name.clone()).unwrap_or_else(|| ins.block.clone());
+        // Charged from the lengths, before any text is copied.
+        let selected_bytes: usize =
+            ins.attribs.iter().filter(|a| selected.contains(&a.tag.to_ascii_uppercase())).map(|a| a.text.value.len() + a.tag.len()).sum();
+        // The constants this row copies (those its own attributes do not override), from the lengths.
+        let first_of_block = !const_sizes.contains_key(&block);
+        let consts_sizes = const_sizes.entry(block.clone()).or_insert_with(|| {
+            d.block(&ins.block).map_or_else(Vec::new, |b| {
+                b.entities
+                    .iter()
+                    .filter_map(|e| match &e.kind {
+                        EntityKind::AttDef(a) if a.constant && selected.iter().any(|t| t == &a.tag.to_ascii_uppercase()) => {
+                            Some((a.tag.to_ascii_uppercase(), a.tag.len() + a.text.value.len()))
+                        }
+                        _ => None,
+                    })
+                    .collect()
+            })
+        });
+        if first_of_block {
+            // The per-block cache of constants is one more copy of them, made once.
+            charge(&mut used, consts_sizes.iter().map(|(_, n)| *n).fold(0, usize::saturating_add), MAX_VALUE_BYTES)?;
+        }
+        let const_bytes: usize = consts_sizes
+            .iter()
+            .filter(|(tag, _)| !ins.attribs.iter().any(|a| a.tag.eq_ignore_ascii_case(tag)))
+            .map(|(_, n)| *n)
+            .fold(0, usize::saturating_add);
+        charge(&mut used, selected_bytes.saturating_add(const_bytes), MAX_VALUE_BYTES)?;
+        let values = values(
+            ins,
+            // Keyed by the resolved definition's exact name: `Part` and `PART` can both exist.
+            consts.entry(block.clone()).or_insert_with(|| d.block(&ins.block).map(|b| constants(b, &selected)).unwrap_or_default()),
+            &selected,
+        );
         out.push(Found {
             handle: e.handle.hex(),
             layer: e.common.layer.clone(),
             at: ins.insert.xy(),
             rotation: ins.rotation.to_degrees(),
             block: block.clone(),
-            values: values(
-                ins,
-                // Keyed by the resolved definition's exact name: `Part` and `PART` can both exist.
-                consts.entry(block.clone()).or_insert_with(|| d.block(&ins.block).map(|b| constants(b, &selected)).unwrap_or_default()),
-                &selected,
-            ),
+            values,
         });
     }
     Ok(out)
@@ -449,6 +495,15 @@ impl Interactive for ExtractM {
 
 #[cfg(test)]
 mod tests {
+    #[test]
+    fn attribute_text_is_charged_against_one_budget() {
+        let mut used = 0;
+        assert!(super::charge(&mut used, 60, 100).is_ok());
+        assert!(super::charge(&mut used, 40, 100).is_ok());
+        assert!(super::charge(&mut used, 1, 100).is_err());
+        assert!(super::charge(&mut used, usize::MAX, 100).is_err());
+    }
+
     use super::*;
 
     #[test]

crates/engine/src/cmd/blocks/xref/bind.rs

@@ -6,7 +6,7 @@
 //! of nested xrefs (`xref|nested|name`) bind with every `|` written `$0$`.
 
 use std::cell::RefCell;
-use std::collections::{BTreeSet, HashMap};
+use std::collections::{BTreeSet, HashMap, HashSet};
 use std::sync::Arc;
 
 use cadcraft_doc::{Drawing, EntityStore, MAX_BLOCK_DEPTH, XrefStatus};
@@ -20,6 +20,16 @@ fn split(name: &str) -> Option<(&str, &str)> {
 
 /// Whether table `sym` of `d` has a symbol called `name`.
 fn taken(d: &Drawing, sym: Sym, name: &str) -> bool {
+    taken_with(d, sym, name, None)
+}
+
+/// [`taken`], answering for blocks from `blocks` (the upper-cased names of `d`'s blocks, kept
+/// current by the caller) when given: a lookup that misses scans every block, which a bind
+/// naming thousands of blocks would repeat for each.
+fn taken_with(d: &Drawing, sym: Sym, name: &str, blocks: Option<&HashSet<String>>) -> bool {
+    if let (Sym::Block, Some(set)) = (sym, blocks) {
+        return set.contains(&name.to_ascii_uppercase());
+    }
     match sym {
         Sym::Layer => d.layer(name).is_some(),
         Sym::Linetype => d.linetype(name).is_some(),
@@ -32,12 +42,12 @@ fn taken(d: &Drawing, sym: Sym, name: &str) -> bool {
 }
 
 /// The bound name of `key|rest`: `key$n$rest` with the first free `n`, or `rest` (Insert type).
-fn bound_name(d: &Drawing, sym: Sym, key: &str, rest: &str, insert: bool) -> String {
+fn bound_name(d: &Drawing, sym: Sym, key: &str, rest: &str, insert: bool, blocks: Option<&HashSet<String>>) -> String {
     let rest = rest.replace('|', "$0$");
     if insert {
         return rest;
     }
-    (0..10_000).map(|n| format!("{key}${n}${rest}")).find(|c| !taken(d, sym, c)).unwrap_or_else(|| format!("{key}$${rest}"))
+    (0..10_000).map(|n| format!("{key}${n}${rest}")).find(|c| !taken_with(d, sym, c, blocks)).unwrap_or_else(|| format!("{key}$${rest}"))
 }
 
 /// Every table's symbol names, for one table at a time.
@@ -53,9 +63,8 @@ fn names(d: &Drawing, sym: Sym) -> Vec<String> {
     }
 }
 
-/// Rename symbol `old` of table `sym` to `new`, or drop it (`new` already exists: Insert type).
-fn rename_symbol(d: &mut Drawing, sym: Sym, old: &str, new: &str) {
-    let merge = !new.eq_ignore_ascii_case(old) && taken(d, sym, new);
+/// Rename symbol `old` of table `sym` to `new`, or drop it (`merge`: `new` already exists, Insert type).
+fn rename_symbol(d: &mut Drawing, sym: Sym, old: &str, new: &str, merge: bool) {
     macro_rules! table {
         ($v:expr) => {{
             if merge {
@@ -101,12 +110,17 @@ pub(crate) fn bind(d: &mut Drawing, key: &str, insert: bool) -> Result<(), Strin
     let mut map: HashMap<(Sym, String), String> = HashMap::new();
     let mut bound_blocks = vec![key.clone()];
     for sym in TABLES {
+        let mut blocks: Option<HashSet<String>> = (sym == Sym::Block).then(|| d.blocks.keys().map(|k| k.to_ascii_uppercase()).collect());
         for old in names(d, sym).into_iter().filter(|n| has_prefix(n, &prefix)) {
             let rest = old.get(prefix.len()..).unwrap_or_default();
-            let new = bound_name(d, sym, &key, rest, insert);
+            let new = bound_name(d, sym, &key, rest, insert, blocks.as_ref());
             // Insert type: a host symbol of the bound name is used instead of the xref's.
-            let merged = taken(d, sym, &new);
-            rename_symbol(d, sym, &old, &new);
+            let merged = taken_with(d, sym, &new, blocks.as_ref());
+            rename_symbol(d, sym, &old, &new, !new.eq_ignore_ascii_case(&old) && merged);
+            if let Some(set) = &mut blocks {
+                set.remove(&old.to_ascii_uppercase());
+                set.insert(new.to_ascii_uppercase());
+            }
             if sym == Sym::Block && !merged {
                 bound_blocks.push(new.clone());
             }
@@ -242,14 +256,27 @@ fn xbind_in(d: &mut Drawing, sym: Sym, name: &str, depth: usize) -> Result<Strin
 mod tests {
     use super::*;
 
+    #[test]
+    fn a_block_name_set_answers_as_the_scan_does() {
+        let mut d = Drawing::new_imperial();
+        for n in ["SITE$0$Plan", "Other"] {
+            d.blocks.insert(n.into(), Arc::new(cadcraft_doc::Block::new(n)));
+        }
+        let set: HashSet<String> = d.blocks.keys().map(|k| k.to_ascii_uppercase()).collect();
+        for n in ["site$0$plan", "SITE$0$Plan", "OTHER", "SITE$1$Plan", "nothing"] {
+            assert_eq!(taken_with(&d, Sym::Block, n, Some(&set)), taken(&d, Sym::Block, n), "{n}");
+        }
+        assert_eq!(bound_name(&d, Sym::Block, "SITE", "plan", false, Some(&set)), "SITE$1$plan");
+    }
+
     #[test]
     fn bound_names() {
         let mut d = Drawing::new_imperial();
-        assert_eq!(bound_name(&d, Sym::Layer, "SITE", "Walls", false), "SITE$0$Walls");
+        assert_eq!(bound_name(&d, Sym::Layer, "SITE", "Walls", false, None), "SITE$0$Walls");
         d.ensure_layer("SITE$0$Walls");
-        assert_eq!(bound_name(&d, Sym::Layer, "SITE", "walls", false), "SITE$1$walls");
-        assert_eq!(bound_name(&d, Sym::Layer, "SITE", "Walls", true), "Walls");
-        assert_eq!(bound_name(&d, Sym::Layer, "SITE", "TREES|Oak", false), "SITE$0$TREES$0$Oak");
+        assert_eq!(bound_name(&d, Sym::Layer, "SITE", "walls", false, None), "SITE$1$walls");
+        assert_eq!(bound_name(&d, Sym::Layer, "SITE", "Walls", true, None), "Walls");
+        assert_eq!(bound_name(&d, Sym::Layer, "SITE", "TREES|Oak", false, None), "SITE$0$TREES$0$Oak");
         assert_eq!(split("A|b|c"), Some(("A", "b|c")));
         assert_eq!(split("|b"), None);
     }

crates/engine/src/cmd/exchange.rs

@@ -497,6 +497,30 @@ fn frame_books(d: &Drawing, frame_height: f64, unit: f64) -> (Vec<Vec<Frame>>, u
     (books, skipped)
 }
 
+/// Most page-by-entity renderings one PDFBOOK may ask for: every page draws the whole model through
+/// its window, so the work is the frames times the model's objects (1,000 sheets of a 500,000-object
+/// drawing).
+const MAX_BOOK_WORK: u64 = 500_000_000;
+
+/// Objects one page draws: the model's objects, and the contents of each block reference (once per
+/// array cell, and the reference's own attributes; nested blocks count as their own entries).
+fn model_visits(d: &Drawing) -> usize {
+    d.model
+        .iter()
+        .map(|e| match &e.kind {
+            EntityKind::Insert(i) => {
+                d.block(&i.block).map_or(1, |b| 1 + b.entities.len().saturating_mul((i.rows as usize).saturating_mul(i.cols as usize)))
+            }
+            _ => 1,
+        })
+        .fold(0usize, usize::saturating_add)
+}
+
+/// Whether `frames` pages of a model with `entities` objects stay within [`MAX_BOOK_WORK`].
+fn book_work_fits(frames: usize, entities: usize) -> bool {
+    (frames as u64).saturating_mul(entities as u64) <= MAX_BOOK_WORK
+}
+
 fn run_pdfbook(s: &mut Session, p: &Value) -> Result<Value> {
     if io().and_then(|h| h.plot).is_none() {
         return Err(bad("pdfbook", "plotting is not available in this build"));
@@ -507,6 +531,13 @@ fn run_pdfbook(s: &mut Session, p: &Value) -> Result<Value> {
     if books.is_empty() {
         return Err(bad("pdfbook", format!("no closed polylines {frame_height} mm high (sheet frames) in model space")));
     }
+    let sheets: usize = books.iter().map(Vec::len).sum();
+    if !book_work_fits(sheets, model_visits(s.doc()?)) {
+        return Err(bad(
+            "pdfbook",
+            format!("{sheets} sheets of a model this large are too much work for one command; plot part of the drawing at a time"),
+        ));
+    }
     let target = str_param(p, "path").map(str::to_string).or_else(|| s.state().ok().and_then(|st| st.path.clone()));
     let pb = target.as_deref().map(std::path::Path::new);
     let dir = pb.and_then(std::path::Path::parent).map(std::path::Path::to_path_buf).unwrap_or_default();
@@ -561,6 +592,13 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn a_book_is_bounded_by_pages_times_objects() {
+        assert!(book_work_fits(1_000, 500_000));
+        assert!(!book_work_fits(100_000, 100_000));
+        assert!(!book_work_fits(usize::MAX, usize::MAX));
+    }
+
     #[test]
     fn web_export_delivers_a_download_instead_of_writing_a_path() {
         deliver_file("export", "Drawing1.svg", b"<svg/>", Some(record)).unwrap();

crates/engine/src/cmd/modify2/ncopy.rs

@@ -7,16 +7,32 @@ use super::{
 // NCOPY
 // =====================================================================================
 
-/// The leaf objects of a block reference in world coordinates (nested references expanded).
-fn nested_leaves(d: &cadcraft_doc::Drawing, ins: &cadcraft_doc::Insert, m: &Mat3, depth: usize, out: &mut Vec<(Common, EntityKind)>) {
+/// Block entities one NCOPY may visit in all, leaves or not: references to shared, empty or
+/// repeated sub-blocks multiply the visits (not the leaves) with each level of nesting.
+const MAX_VISITS: usize = 1_000_000;
+
+/// The leaf objects of a block reference in world coordinates (nested references expanded). An
+/// error when the nesting needs more than [`MAX_VISITS`] visits.
+fn nested_leaves(
+    d: &cadcraft_doc::Drawing,
+    ins: &cadcraft_doc::Insert,
+    m: &Mat3,
+    depth: usize,
+    visits: &mut usize,
+    out: &mut Vec<(Common, EntityKind)>,
+) -> Result<()> {
     if depth >= MAX_BLOCK_DEPTH || out.len() >= MAX_GEN {
-        return;
+        return Ok(());
     }
-    let Some(b) = d.block(&ins.block) else { return };
+    let Some(b) = d.block(&ins.block) else { return Ok(()) };
     let mm = m.then_before(ins.transform(b.base.xy()));
     for e in b.entities.iter() {
+        *visits += 1;
+        if *visits > MAX_VISITS {
+            return Err(other("The block reference nests too many objects to copy."));
+        }
         match &e.kind {
-            EntityKind::Insert(inner) => nested_leaves(d, inner, &mm, depth + 1, out),
+            EntityKind::Insert(inner) => nested_leaves(d, inner, &mm, depth + 1, visits, out)?,
             EntityKind::AttDef(_) => {}
             k => {
                 let mut k = k.clone();
@@ -25,13 +41,14 @@ fn nested_leaves(d: &cadcraft_doc::Drawing, ins: &cadcraft_doc::Insert, m: &Mat3
             }
         }
     }
+    Ok(())
 }
 
-fn leaves_of(s: &Session, h: Handle) -> Result<Vec<(Common, EntityKind)>> {
+fn leaves_of(s: &Session, h: Handle, visits: &mut usize) -> Result<Vec<(Common, EntityKind)>> {
     let e = curves::entity(s, h)?;
     let EntityKind::Insert(ins) = &e.kind else { return Err(other("Select a block reference.")) };
     let mut out = Vec::new();
-    nested_leaves(s.doc()?, ins, &Mat3::IDENTITY, 0, &mut out);
+    nested_leaves(s.doc()?, ins, &Mat3::IDENTITY, 0, visits, &mut out)?;
     Ok(out)
 }
 
@@ -53,7 +70,7 @@ fn place_copies(s: &mut Session, items: &[(Common, EntityKind)], delta: Vec2) ->
 
 pub(super) fn run_ncopy(s: &mut Session, p: &Value) -> Result<Value> {
     let h = targets(s, p)?.first().copied().ok_or_else(|| bad("ncopy", "`handle` (block reference) is required"))?;
-    let leaves = leaves_of(s, h)?;
+    let leaves = leaves_of(s, h, &mut 0)?;
     let items: Vec<(Common, EntityKind)> = match point_param(p, "pick") {
         Some(q) => nearest_leaf(leaves, q).into_iter().collect(),
         None => leaves,
@@ -74,6 +91,8 @@ pub(super) fn run_ncopy(s: &mut Session, p: &Value) -> Result<Value> {
 pub(super) struct NcopyM {
     items: Vec<(Common, EntityKind)>,
     selecting_done: bool,
+    /// Block entities visited by every selection so far: one allowance for the whole command.
+    visits: usize,
     base: Option<Vec2>,
 }
 
@@ -97,7 +116,7 @@ impl Interactive for NcopyM {
             return match i {
                 Input::Point(p) => {
                     let h = curves::pick_at(s, p).ok_or_else(|| other("*Invalid selection*"))?;
-                    let leaf = nearest_leaf(leaves_of(s, h)?, p).ok_or_else(|| other("Nothing nested there."))?;
+                    let leaf = nearest_leaf(leaves_of(s, h, &mut self.visits)?, p).ok_or_else(|| other("Nothing nested there."))?;
                     s.echo(format!("Nested object: {}", leaf.1.type_name()));
                     if self.items.len() < MAX_GEN {
                         self.items.push(leaf);

crates/engine/src/cmd/modify2/tests.rs

@@ -777,3 +777,25 @@ fn offset_elliptical_arc_follows_picked_side() {
     let outer = max_x(json!([20, 20]));
     assert!((outer - 11.0).abs() < 0.05, "outer side went inward: max x = {outer}");
 }
+
+/// Nested references multiply visits even when no leaf results; NCOPY refuses past its visit budget.
+#[test]
+fn ncopy_charges_every_nested_visit() {
+    use cadcraft_doc::{Block, Common, Entity, Insert};
+    let mut s = Session::new();
+    let d = s.doc_mut().unwrap();
+    let mut n = 1;
+    for level in 0..15 {
+        let mut b = Block::new(&format!("B{level}"));
+        for _ in 0..100 {
+            let ins = Insert { block: format!("B{}", level + 1), ..Insert::default() };
+            b.entities.push(Entity::new(Handle(n), EntityKind::Insert(ins)));
+            n += 1;
+        }
+        d.blocks.insert(b.name.clone(), std::sync::Arc::new(b));
+    }
+    d.blocks.insert("B15".into(), std::sync::Arc::new(Block::new("B15")));
+    let h = d.add(&Space::Model, Common::default(), EntityKind::Insert(Insert { block: "B0".into(), ..Insert::default() })).unwrap();
+    let err = s.execute("ncopy", &json!({ "handle": h.hex() })).unwrap_err().to_string();
+    assert!(err.contains("nests too many objects"), "{err}");
+}

crates/engine/src/lisp.rs

@@ -697,7 +697,7 @@ impl Session {
 }
 
 pub(crate) use drawing::from_json as drawing_from_json;
-pub(crate) use drawing::load_source;
+pub(crate) use drawing::{load_source, support_file};
 
 impl Session {
     /// A file APPLOAD loaded, by its name (with or without `.lsp`, any case).

crates/engine/src/lisp/builtins/functions.rs

@@ -235,7 +235,8 @@ pub(super) fn autoload(ctx: &mut Ctx<'_>, a: Vec<Value>) -> Result<Flow, LispErr
             return Err(LispError::bad_arg("command name", &cmd));
         }
         // The stub forgets itself, loads the file and calls what it defined.
-        let file_lit = to_text(&Value::Str(file.clone()), true);
+        // A file in the support folder is loaded from there, never from a same-named file of the working folder.
+        let file_lit = to_text(&Value::Str(crate::lisp::support_file(ctx.s, &file).map_or_else(|| file.clone(), |p| p.into())), true);
         let src = format!(
             "(lambda () (setq C:{name} nil) (load {file_lit}) (if C:{name} (C:{name}) (princ \"\\n; error: {} did not define {name}\")) (princ))",
             file.replace(['"', '\\'], "/")

crates/engine/src/lisp/drawing.rs

@@ -1128,7 +1128,9 @@ pub fn trans(_ctx: &mut Ctx<'_>, a: Vec<Value>) -> Result<Flow, LispError> {
 /// What `(load name)` reads: a file loaded through APPLOAD (the web), or one on disk, with
 /// `.lsp` added when the name has no extension.
 pub fn load_source(s: &Session, name: &str) -> Option<String> {
-    if let Some(t) = s.lisp_file(name) {
+    // An absolute path names a file, not an APPLOAD entry that happens to share its base name.
+    let absolute = std::path::Path::new(name).is_absolute();
+    if !absolute && let Some(t) = s.lisp_file(name) {
         return Some(t);
     }
     let candidates =
@@ -1139,10 +1141,37 @@ pub fn load_source(s: &Session, name: &str) -> Option<String> {
     candidates.iter().chain(&support).find_map(super::builtins::read_text_file)
 }
 
+/// The file `name` names in the support folder, when it is there: what an autoload registration
+/// loads, so a same-named file in the working folder cannot take its place. `None` for an absolute
+/// path, no support folder or no such file there (the general search then applies, as before).
+pub fn support_file(s: &Session, name: &str) -> Option<String> {
+    if std::path::Path::new(name).is_absolute() {
+        return None;
+    }
+    let dir = s.lisp_support_dir()?;
+    let candidates =
+        if std::path::Path::new(name).extension().is_none() { vec![format!("{name}.lsp"), name.to_string()] } else { vec![name.to_string()] };
+    candidates.iter().map(|c| dir.join(c)).find(|p| p.is_file()).map(|p| std::path::absolute(&p).unwrap_or(p).to_string_lossy().into_owned())
+}
+
 #[cfg(test)]
 mod budget_tests {
     use super::*;
 
+    #[test]
+    fn autoload_prefers_the_support_folder_file() {
+        let dir = std::env::temp_dir().join(format!("cadcraft-lisp-support-file-{}", std::process::id()));
+        std::fs::create_dir_all(&dir).unwrap();
+        std::fs::write(dir.join("lazy.lsp"), "").unwrap();
+        let mut s = Session::new();
+        assert_eq!(support_file(&s, "lazy"), None);
+        s.set_lisp_support_dir(Some(dir.clone()));
+        assert_eq!(support_file(&s, "lazy"), Some(dir.join("lazy.lsp").to_string_lossy().into_owned()));
+        assert_eq!(support_file(&s, "other"), None);
+        assert_eq!(support_file(&s, dir.join("lazy.lsp").to_str().unwrap()), None);
+        let _ = std::fs::remove_dir_all(&dir);
+    }
+
     /// One 64 KB string occurring many times is charged by its length each time.
     #[test]
     fn shared_strings_spend_the_conversion_budgets() {

crates/render/src/blocks.rs

@@ -12,17 +12,16 @@ pub(crate) fn sub_ctx<'a>(ctx: &Ctx<'a>, e: &Entity, m: Mat3) -> Ctx<'a> {
     };
     let lw = match e.common.lineweight {
         Lineweight::ByBlock => ctx.block_lw,
-        Lineweight::ByLayer => ctx.layer(layer.as_deref().unwrap_or("0")).map(|l| l.lineweight).unwrap_or(Lineweight::Default),
+        Lineweight::ByLayer => ctx.d.layer(layer.as_deref().unwrap_or("0")).map(|l| l.lineweight).unwrap_or(Lineweight::Default),
         x => x,
     };
     let lt = match e.common.linetype.to_ascii_lowercase().as_str() {
         "byblock" => ctx.block_ltype.clone(),
-        "bylayer" => ctx.layer(layer.as_deref().unwrap_or("0")).map(|l| l.linetype.clone()).unwrap_or_else(|| "Continuous".into()),
+        "bylayer" => ctx.d.layer(layer.as_deref().unwrap_or("0")).map(|l| l.linetype.clone()).unwrap_or_else(|| "Continuous".into()),
         _ => e.common.linetype.clone(),
     };
     Ctx {
         d: ctx.d,
-        layers: ctx.layers,
         xf: ctx.xf.then_before(m),
         block_color: color,
         block_layer: layer,

crates/render/src/clip.rs

@@ -256,16 +256,8 @@ pub struct PolyClip {
     band_h: f64,
     /// The region as triangles (for clipping fills), with each triangle's bounds.
     tris: Vec<([Vec2; 3], Bounds2)>,
-    /// Indices into `tris` of the triangles whose y range meets each band (at most
-    /// [`TRI_BAND_SPAN`] bands of it), so a fill triangle meets only the clip triangles near it.
-    tri_bands: Vec<Vec<u32>>,
-    /// Indices of the triangles spanning more bands than that: tested against every fill triangle.
-    tall_tris: Vec<u32>,
 }
 
-/// Most bands one clip triangle is registered in; a taller one goes to [`PolyClip::tall_tris`].
-const TRI_BAND_SPAN: usize = 8;
-
 impl PolyClip {
     /// A clip region for `poly` (see [`clean_polygon`]); `None` for a degenerate outline.
     pub fn new(poly: &[Vec2]) -> Option<PolyClip> {
@@ -274,15 +266,7 @@ impl PolyClip {
         let band_h = bounds.height() / BANDS as f64;
         let mut bands: Vec<Vec<u32>> = vec![Vec::new(); BANDS];
         let n = poly.len();
-        let mut clip = PolyClip {
-            poly: Vec::new(),
-            bounds,
-            bands: Vec::new(),
-            band_h,
-            tris: Vec::new(),
-            tri_bands: vec![Vec::new(); BANDS],
-            tall_tris: Vec::new(),
-        };
+        let mut clip = PolyClip { poly: Vec::new(), bounds, bands: Vec::new(), band_h, tris: Vec::new() };
         for i in 0..n {
             let (Some(a), Some(b)) = (poly.get(i), poly.get((i + 1) % n)) else { continue };
             let (lo, hi) = (clip.band(a.y.min(b.y)), clip.band(a.y.max(b.y)));
@@ -298,17 +282,6 @@ impl PolyClip {
             .map(|t| (*t, Bounds2::from_points(t.iter().copied())))
             .filter(|(_, b)| b.width() > 0.0 && b.height() > 0.0)
             .collect();
-        for k in 0..clip.tris.len() {
-            let Some((_, tb)) = clip.tris.get(k) else { continue };
-            let (lo, hi) = (clip.band(tb.min.y), clip.band(tb.max.y));
-            if hi - lo >= TRI_BAND_SPAN {
-                clip.tall_tris.push(k as u32);
-            } else {
-                for band in clip.tri_bands.iter_mut().take(hi + 1).skip(lo) {
-                    band.push(k as u32);
-                }
-            }
-        }
         clip.poly = poly;
         clip.bands = bands;
         Some(clip)
@@ -431,15 +404,7 @@ impl PolyClip {
                 out.extend_from_slice(t);
                 continue;
             }
-            // The clip triangles near `t`, in clip order (the same output as a scan of all of them).
-            let (lo, hi) = (self.band(tb.min.y), self.band(tb.max.y));
-            let mut near: Vec<u32> = self.tall_tris.clone();
-            for band in self.tri_bands.iter().take(hi + 1).skip(lo) {
-                near.extend_from_slice(band);
-            }
-            near.sort_unstable();
-            near.dedup();
-            for (c, cb) in near.iter().filter_map(|&k| self.tris.get(k as usize)) {
+            for (c, cb) in &self.tris {
                 if !cb.intersects(&tb) {
                     continue;
                 }
@@ -625,39 +590,6 @@ mod tests {
         assert!(t.iter().all(|p| !(p.x > 5.0 + 1e-9 && p.y > 5.0 + 1e-9)));
     }
 
-    /// A fill clipped through the band index equals the same fill against a plain scan of every clip
-    /// triangle (the unindexed result), for a boundary with tall and short triangles.
-    #[test]
-    fn indexed_triangle_clipping_equals_a_full_scan() {
-        // A comb: tall teeth over a base, so its triangles span many bands.
-        let mut poly = vec![Vec2::new(0.0, 0.0), Vec2::new(40.0, 0.0)];
-        for i in (0..20).rev() {
-            let x = i as f64 * 2.0;
-            poly.extend([
-                Vec2::new(x + 2.0, 20.0),
-                Vec2::new(x + 1.0, 20.0),
-                Vec2::new(x + 1.0, 2.0),
-                Vec2::new(x + 0.5, 2.0),
-                Vec2::new(x + 0.5, 20.0),
-                Vec2::new(x, 20.0),
-            ]);
-        }
-        let c = PolyClip::new(&poly).unwrap();
-        assert!(!c.tall_tris.is_empty());
-        let fill: Vec<Vec2> = (0..30)
-            .flat_map(|i| {
-                let (x, y) = (i as f64 * 1.3, (i % 7) as f64 * 2.5);
-                [Vec2::new(x, y), Vec2::new(x + 6.0, y), Vec2::new(x + 2.0, y + 9.0)]
-            })
-            .collect();
-        let got = c.clip_triangles(&fill);
-        let mut scan = c.clone();
-        scan.tri_bands = vec![(0..scan.tris.len() as u32).collect(); BANDS];
-        scan.tall_tris.clear();
-        assert_eq!(got, scan.clip_triangles(&fill));
-        assert!(!got.is_empty());
-    }
-
     #[test]
     fn degenerate_and_hostile_outlines() {
         assert!(PolyClip::new(&[Vec2::new(0.0, 0.0), Vec2::new(1.0, 1.0)]).is_none());

crates/render/src/dim_draw.rs

@@ -42,7 +42,7 @@ pub(crate) fn dimension(
     let dim_rgb = ink(style.dim_line_color, layer_color, own);
     let ext_rgb = ink(style.ext_line_color, layer_color, own);
     let txt_rgb = ink(style.text_color, layer_color, own);
-    let layer = ctx.layer(layer_name);
+    let layer = d.layer(layer_name);
     let weight = |v: i16| -> f32 {
         if !b.opts.lineweights {
             return 0.0;

crates/render/src/fill.rs

@@ -1,109 +1,40 @@
 //! Polygon filling: even-odd regions to triangles (slab decomposition), wide polylines.
 
 use cadcraft_doc::LwPolyline;
-use cadcraft_geom::{Bounds2, Polyline, Vec2};
+use cadcraft_geom::{Polyline, Vec2};
 
 /// Triangulate an even-odd region bounded by closed loops (holes allowed) by cutting it into
 /// horizontal slabs at every vertex y and emitting trapezoids. Two edges that cross inside a slab
 /// (a bowtie, two loops crossing each other) swap order there, so such a slab is cut again at the
 /// crossing and each part is paired on its own. Robust for any input; output size is
-/// O(slabs × crossings), capped for hostile inputs. Groups of loops whose bounding boxes are
-/// separated (by a vertical or a horizontal gap, recursively) cannot affect each other's even-odd
-/// parity, so each group is cut on its own: disjoint outlines do not multiply each other's slabs.
+/// O(slabs × crossings), capped for hostile inputs.
 pub fn triangulate_evenodd(loops: &[Vec<Vec2>]) -> Vec<Vec2> {
-    // (original index, bounds, edges) per loop.
-    let mut items: Vec<(usize, Bounds2, Vec<(Vec2, Vec2)>)> = Vec::new();
-    let mut total = 0usize;
-    for (k, l) in loops.iter().enumerate() {
+    let mut edges: Vec<(Vec2, Vec2)> = Vec::new();
+    for l in loops {
         let n = l.len();
         if n < 3 {
             continue;
         }
-        let mut edges = Vec::new();
         for i in 0..n {
             let (Some(&a), Some(&b)) = (l.get(i), l.get((i + 1) % n)) else { continue };
             if (a.y - b.y).abs() > 1e-15 && a.is_finite() && b.is_finite() {
                 edges.push(if a.y < b.y { (a, b) } else { (b, a) });
             }
         }
-        total += edges.len();
-        if total > 200_000 {
-            return Vec::new();
-        }
-        if !edges.is_empty() {
-            let bounds = Bounds2::from_points(edges.iter().flat_map(|(a, b)| [*a, *b]));
-            items.push((k, bounds, edges));
-        }
     }
-    let mut out = Vec::new();
-    // Slabs created by cutting at crossings, over the whole region; past this the remaining
-    // crossings are left unsplit rather than letting a hostile input run away.
-    let mut cuts_left = MAX_CROSSING_CUTS;
-    // Loop visits all the partitioning may make: an input that peels one loop off a big group at a
-    // time would rescan the rest each time, so past this a group is cut as it stands (as before partitioning existed).
-    let mut split_work = 64 * items.len() + 4_000_000;
-    let mut stack = vec![items];
-    while let Some(mut group) = stack.pop() {
-        if group.is_empty() {
-            continue;
-        }
-        let parts = match split_work.checked_sub(2 * group.len()) {
-            Some(rest) => {
-                split_work = rest;
-                let parts = split_groups(&mut group, true);
-                if parts.len() > 1 { parts } else { split_groups(&mut group, false) }
-            }
-            None => Vec::new(),
-        };
-        if parts.len() > 1 {
-            // Lowest-first when popped.
-            stack.extend(parts.into_iter().rev());
-            continue;
-        }
-        group.sort_by_key(|g| g.0);
-        let edges: Vec<(Vec2, Vec2)> = group.into_iter().flat_map(|g| g.2).collect();
-        if slabs(edges, &mut out, &mut cuts_left) {
-            break;
-        }
+    if edges.is_empty() || edges.len() > 200_000 {
+        return Vec::new();
     }
-    out
-}
-
-type Item = (usize, Bounds2, Vec<(Vec2, Vec2)>);
-
-/// `group` cut into the chains of loops whose extents along x (or y) overlap, in order along it;
-/// one chain when nothing separates them (then `group` is left as it was, but for its order).
-fn split_groups(group: &mut Vec<Item>, along_x: bool) -> Vec<Vec<Item>> {
-    let span = |b: &Bounds2| if along_x { (b.min.x, b.max.x) } else { (b.min.y, b.max.y) };
-    group.sort_by(|a, b| span(&a.1).0.total_cmp(&span(&b.1).0));
-    let mut parts: Vec<Vec<Item>> = Vec::new();
-    let mut reach = f64::NEG_INFINITY;
-    for item in std::mem::take(group) {
-        match parts.last_mut() {
-            Some(part) if span(&item.1).0 <= reach => {
-                reach = reach.max(span(&item.1).1);
-                part.push(item);
-            }
-            _ => {
-                reach = span(&item.1).1;
-                parts.push(vec![item]);
-            }
-        }
-    }
-    if parts.len() == 1 {
-        *group = parts.pop().unwrap_or_default();
-    }
-    parts
-}
-
-/// The slab decomposition of `edges` appended to `out`; true once `out` passes its cap.
-fn slabs(mut edges: Vec<(Vec2, Vec2)>, out: &mut Vec<Vec2>, cuts_left: &mut usize) -> bool {
     let mut ys: Vec<f64> = edges.iter().flat_map(|(a, b)| [a.y, b.y]).collect();
     ys.sort_by(f64::total_cmp);
     ys.dedup_by(|a, b| (*a - *b).abs() < 1e-12);
     edges.sort_by(|a, b| a.0.y.total_cmp(&b.0.y));
+    let mut out = Vec::new();
     let mut active: Vec<(Vec2, Vec2)> = Vec::new();
     let mut next = 0usize;
+    // Slabs created by cutting at crossings, over the whole region; past this the remaining
+    // crossings are left unsplit rather than letting a hostile input run away.
+    let mut cuts_left = MAX_CROSSING_CUTS;
     let mut pending: Vec<(f64, f64)> = Vec::new();
     for w in ys.windows(2) {
         let (Some(&y0), Some(&y1)) = (w.first(), w.get(1)) else { continue };
@@ -123,7 +54,7 @@ fn slabs(mut edges: Vec<(Vec2, Vec2)>, out: &mut Vec<Vec2>, cuts_left: &mut usiz
             let ymid = (ya + yb) / 2.0;
             let mut xs: Vec<(f64, f64, f64)> = active.iter().map(|e| (x_at(e, ymid), x_at(e, ya), x_at(e, yb))).collect();
             xs.sort_by(|a, b| a.0.total_cmp(&b.0));
-            if *cuts_left > 0 {
+            if cuts_left > 0 {
                 let mut cuts: Vec<f64> = Vec::new();
                 for pair in xs.windows(2) {
                     let (Some(l), Some(r)) = (pair.first(), pair.get(1)) else { continue };
@@ -134,8 +65,8 @@ fn slabs(mut edges: Vec<(Vec2, Vec2)>, out: &mut Vec<Vec2>, cuts_left: &mut usiz
                 if !cuts.is_empty() {
                     cuts.sort_by(f64::total_cmp);
                     cuts.dedup_by(|a, b| (*a - *b).abs() < 1e-12);
-                    cuts.truncate(*cuts_left);
-                    *cuts_left -= cuts.len();
+                    cuts.truncate(cuts_left);
+                    cuts_left -= cuts.len();
                     // Push the parts top-down so the lowest is processed first.
                     let mut top = yb;
                     for &c in cuts.iter().rev() {
@@ -153,11 +84,11 @@ fn slabs(mut edges: Vec<(Vec2, Vec2)>, out: &mut Vec<Vec2>, cuts_left: &mut usiz
                 }
             }
             if out.len() > 6_000_000 {
-                return true;
+                return out;
             }
         }
     }
-    false
+    out
 }
 
 /// How many extra slab boundaries crossings may add over one region.
@@ -233,40 +164,6 @@ mod tests {
         assert!((area(&t) - 96.0).abs() < 1e-9);
     }
 
-    /// A thousand disjoint squares side by side (every slab of one would otherwise be cut at the
-    /// vertex heights of all the others) triangulate in linear output.
-    #[test]
-    fn disjoint_outlines_do_not_multiply_each_others_slabs() {
-        let n = 1_000;
-        let loops: Vec<Vec<Vec2>> = (0..n)
-            .map(|i| {
-                let (x, jitter) = (i as f64 * 3.0, i as f64 * 0.001);
-                vec![Vec2::new(x, jitter), Vec2::new(x + 2.0, jitter), Vec2::new(x + 2.0, 2.0 + jitter), Vec2::new(x, 2.0 + jitter)]
-            })
-            .collect();
-        let t = triangulate_evenodd(&loops);
-        assert!((area(&t) - 4.0 * n as f64).abs() < 1e-6);
-        // Two triangles per square: no slab was cut at another square's height.
-        assert_eq!(t.len(), 6 * n);
-    }
-
-    /// Rectangles that peel off one at a time along alternating axes (each split isolates a single loop
-    /// from a large group) still triangulate correctly, with the partition work bounded.
-    #[test]
-    fn alternating_peeling_is_bounded_and_correct() {
-        let m = 1_000;
-        let (mf, mut loops) = (m as f64, Vec::new());
-        let rect = |x0: f64, x1: f64, y0: f64, y1: f64| vec![Vec2::new(x0, y0), Vec2::new(x1, y0), Vec2::new(x1, y1), Vec2::new(x0, y1)];
-        for i in 0..m {
-            let i = i as f64;
-            loops.push(rect(2.0 * i, 2.0 * i + 1.0, 2.0 * i, 2.0 * mf));
-            loops.push(rect(2.0 * i + 2.0, 2.0 * mf + 1.0, 2.0 * i, 2.0 * i + 1.0));
-        }
-        let expected: f64 = (0..m).map(|i| (2.0 * mf - 2.0 * i as f64) + (2.0 * mf - 2.0 * i as f64 - 1.0)).sum();
-        let t = triangulate_evenodd(&loops);
-        assert!((area(&t) - expected).abs() < 1e-6 * expected, "{} vs {expected}", area(&t));
-    }
-
     #[test]
     fn triangle_area() {
         let t = triangulate_evenodd(&[vec![Vec2::new(0.0, 0.0), Vec2::new(4.0, 0.0), Vec2::new(0.0, 3.0)]]);

crates/render/src/lib.rs

@@ -78,32 +78,10 @@ fn max_scale(m: &Mat3) -> f64 {
     if s.is_finite() { s } else { 0.0 }
 }
 
-/// A drawing's layers by lower-cased name (the first of a duplicated name wins, as the table's own
-/// search does), built once per display list: a lookup per object over the layer vector multiplies
-/// the object count by the layer count.
-struct LayerIndex(Option<std::collections::HashMap<String, usize>>);
-
-impl LayerIndex {
-    fn new(d: &Drawing) -> Self {
-        let mut m = std::collections::HashMap::with_capacity(d.layers.len());
-        for (i, l) in d.layers.iter().enumerate() {
-            m.entry(l.name.to_ascii_lowercase()).or_insert(i);
-        }
-        LayerIndex(Some(m))
-    }
-
-    /// No index: lookups scan the layer vector, as `Drawing::layer` does. For a few objects (a
-    /// rubber band redrawn at every pointer move), where building an index would cost more.
-    fn linear() -> Self {
-        LayerIndex(None)
-    }
-}
-
 /// Graphics state inherited through block references.
 #[derive(Clone)]
 struct Ctx<'a> {
     d: &'a Drawing,
-    layers: &'a LayerIndex,
     xf: Mat3,
     block_color: Color,
     block_layer: Option<String>,
@@ -125,19 +103,12 @@ struct Ctx<'a> {
 }
 
 impl Ctx<'_> {
-    /// The layer called `name` (any case), as [`Drawing::layer`] finds it.
-    fn layer(&self, name: &str) -> Option<&cadcraft_doc::Layer> {
-        let Some(map) = &self.layers.0 else { return self.d.layer(name) };
-        let i = if name.bytes().any(|b| b.is_ascii_uppercase()) { map.get(&name.to_ascii_lowercase()) } else { map.get(name) };
-        i.and_then(|i| self.d.layers.get(*i))
-    }
-
     /// A layer's colour, honouring the viewport's override.
     fn layer_color(&self, name: &str) -> Option<Color> {
         if let Some((_, c)) = self.vp_colors.iter().find(|(n, _)| n.eq_ignore_ascii_case(name)) {
             return Some(*c);
         }
-        self.layer(name).map(|l| l.color)
+        self.d.layer(name).map(|l| l.color)
     }
 }
 
@@ -154,8 +125,6 @@ struct Builder<'a> {
     shared_budget: Option<&'a std::sync::atomic::AtomicUsize>,
     /// Transparency (percent) of the entity being drawn.
     transparency: u8,
-    /// The drawing's layers by name.
-    layers: &'a LayerIndex,
 }
 
 /// Upper bound on the block contents drawn per display list (each block reference, MINSERT copy
@@ -371,7 +340,6 @@ impl<'a> Builder<'a> {
             named: self.named,
             shared_budget: self.shared_budget,
             transparency: self.transparency,
-            layers: self.layers,
         }
     }
     /// Take one unit of the block-expansion budget; false once it is spent.

crates/render/src/pipeline.rs

@@ -3,9 +3,7 @@ use super::display::append;
 use super::display::{DisplayList, Kind, NO_LAYER, PlotText, VIEWPORT_CONTENT};
 use super::draw::entity;
 use super::viewports::{MAX_VIEWPORTS, viewport};
-use super::{
-    Bounds2, Builder, Color, Ctx, Drawing, Entity, EntityKind, Handle, LayerIndex, Lineweight, Mat3, Space, Vec2, paper, pen, plotstyle, point,
-};
+use super::{Bounds2, Builder, Color, Ctx, Drawing, Entity, EntityKind, Handle, Lineweight, Mat3, Space, Vec2, paper, pen, plotstyle, point};
 
 /// Build options.
 #[derive(Clone, Debug)]
@@ -82,17 +80,9 @@ pub fn build_plot(d: &Drawing, space: &Space, opts: &Options) -> DisplayList {
     build_space(d, space, opts, true)
 }
 
-pub(crate) fn top_ctx<'a>(
-    d: &'a Drawing,
-    layers: &'a LayerIndex,
-    xf: Mat3,
-    top: Handle,
-    frozen: &'a [String],
-    vp_colors: &'a [(String, Color)],
-) -> Ctx<'a> {
+pub(crate) fn top_ctx<'a>(d: &'a Drawing, xf: Mat3, top: Handle, frozen: &'a [String], vp_colors: &'a [(String, Color)]) -> Ctx<'a> {
     Ctx {
         d,
-        layers,
         xf,
         block_color: Color::Index(7),
         block_layer: None,
@@ -111,17 +101,7 @@ pub(crate) fn top_ctx<'a>(
 fn build_space(d: &Drawing, space: &Space, opts: &Options, plotting: bool) -> DisplayList {
     let opts = &with_point_view(d, space, opts);
     let styler = style_table(d, space, opts, plotting).map(|t| plotstyle::Styler::new(d, t));
-    let layers = LayerIndex::new(d);
-    let mut b = Builder {
-        list: DisplayList::default(),
-        opts,
-        plotting,
-        styles: styler.as_ref(),
-        named: None,
-        shared_budget: None,
-        transparency: 0,
-        layers: &layers,
-    };
+    let mut b = Builder { list: DisplayList::default(), opts, plotting, styles: styler.as_ref(), named: None, shared_budget: None, transparency: 0 };
     if let Space::Paper(name) = space {
         b.list.sheet = paper::sheet(d, name);
     }
@@ -144,7 +124,7 @@ fn build_space(d: &Drawing, space: &Space, opts: &Options, plotting: bool) -> Di
                 }
                 continue;
             }
-            entity(&mut b, &top_ctx(d, &layers, Mat3::IDENTITY, e.handle, &[], &[]), e);
+            entity(&mut b, &top_ctx(d, Mat3::IDENTITY, e.handle, &[], &[]), e);
         }
     }
     // A layout is drawn in paper units, so its pens become geometry now.
@@ -168,22 +148,14 @@ fn build_parallel(b: &mut Builder, d: &Drawing, store: &cadcraft_doc::EntityStor
     use rayon::prelude::*;
     let ents: Vec<&std::sync::Arc<Entity>> = store.iter().collect();
     let budget = std::sync::atomic::AtomicUsize::new(0);
-    let (opts, plotting, layers) = (b.opts, b.plotting, b.layers);
+    let (opts, plotting) = (b.opts, b.plotting);
     let parts: Vec<DisplayList> = ents
         .par_chunks(PARALLEL_CHUNK)
         .map(|chunk| {
-            let mut part = Builder {
-                list: DisplayList::default(),
-                opts,
-                plotting,
-                styles: None,
-                named: None,
-                shared_budget: Some(&budget),
-                transparency: 0,
-                layers,
-            };
+            let mut part =
+                Builder { list: DisplayList::default(), opts, plotting, styles: None, named: None, shared_budget: Some(&budget), transparency: 0 };
             for e in chunk {
-                entity(&mut part, &top_ctx(d, layers, Mat3::IDENTITY, e.handle, &[], &[]), e);
+                entity(&mut part, &top_ctx(d, Mat3::IDENTITY, e.handle, &[], &[]), e);
             }
             part.list
         })
@@ -222,10 +194,6 @@ pub(crate) fn with_point_view(d: &Drawing, space: &Space, opts: &Options) -> Opt
     o
 }
 
-/// Loose entity lists shorter than this, with no block reference (whose contents expand to many
-/// objects), look layers up by scanning rather than building an index.
-const SMALL_LIST: usize = 64;
-
 /// Build the display list for a set of loose entities (previews, rubber bands).
 pub fn build_entities<'a, I: IntoIterator<Item = &'a Entity>>(d: &Drawing, ents: I, opts: &Options) -> DisplayList {
     let ents: Vec<&Entity> = ents.into_iter().collect();
@@ -237,23 +205,9 @@ pub fn build_entities<'a, I: IntoIterator<Item = &'a Entity>>(d: &Drawing, ents:
     } else {
         opts
     };
-    let layers = if ents.len() < SMALL_LIST && !ents.iter().any(|e| matches!(e.kind, EntityKind::Insert(_))) {
-        LayerIndex::linear()
-    } else {
-        LayerIndex::new(d)
-    };
-    let mut b = Builder {
-        list: DisplayList::default(),
-        opts,
-        plotting: false,
-        styles: None,
-        named: None,
-        shared_budget: None,
-        transparency: 0,
-        layers: &layers,
-    };
+    let mut b = Builder { list: DisplayList::default(), opts, plotting: false, styles: None, named: None, shared_budget: None, transparency: 0 };
     for e in ents {
-        entity(&mut b, &top_ctx(d, &layers, Mat3::IDENTITY, e.handle, &[], &[]), e);
+        entity(&mut b, &top_ctx(d, Mat3::IDENTITY, e.handle, &[], &[]), e);
     }
     b.list
 }

crates/render/src/plotstyle.rs

@@ -59,7 +59,7 @@ impl Styler {
         let normal = || by_name(cadcraft_doc::NORMAL_STYLE);
         let p = c.plot_style.trim();
         if p.is_empty() || p.eq_ignore_ascii_case("bylayer") {
-            ctx.layer(layer_name).and_then(|l| by_name(&l.plot_style)).or_else(normal)
+            ctx.d.layer(layer_name).and_then(|l| by_name(&l.plot_style)).or_else(normal)
         } else if p.eq_ignore_ascii_case("byblock") {
             ctx.block_pstyle.or_else(normal)
         } else {

crates/render/src/props.rs

@@ -14,7 +14,7 @@ pub(crate) fn resolve_common(ctx: &Ctx, c: &cadcraft_doc::Common, plotting: bool
     let d = ctx.d;
     // Layer "0" inside a block takes the insert's layer.
     let layer_name = if c.layer == "0" { ctx.block_layer.as_deref().unwrap_or("0") } else { c.layer.as_str() };
-    let layer = ctx.layer(layer_name);
+    let layer = d.layer(layer_name);
     let visible =
         c.visible && layer.is_none_or(|l| l.visible() && (!plotting || l.plot)) && !ctx.frozen.iter().any(|f| f.eq_ignore_ascii_case(layer_name));
     let layer_color = ctx.layer_color(layer_name).unwrap_or(Color::Index(7));

crates/render/src/tests.rs

@@ -1217,20 +1217,3 @@ fn rotated_and_reversed_copies_of_a_curved_loop_fill_once() {
     });
     assert_eq!(loops_of(&h).len(), 2);
 }
-
-/// The per-list layer index finds what `Drawing::layer` finds: any case, the first of a duplicate.
-#[test]
-fn the_layer_index_agrees_with_the_layer_table() {
-    let mut d = Drawing::new_imperial();
-    let mut first = cadcraft_doc::Layer::new("Walls");
-    first.color = Color::Index(1);
-    let mut dup = cadcraft_doc::Layer::new("WALLS");
-    dup.color = Color::Index(2);
-    d.layers.extend([first, dup, cadcraft_doc::Layer::new("Doors")]);
-    for index in [LayerIndex::new(&d), LayerIndex::linear()] {
-        let top = crate::pipeline::top_ctx(&d, &index, cadcraft_geom::Mat3::IDENTITY, cadcraft_doc::Handle(1), &[], &[]);
-        for name in ["Walls", "walls", "WALLS", "doors", "0", "Missing"] {
-            assert_eq!(top.layer(name).map(|l| (&l.name, l.color)), d.layer(name).map(|l| (&l.name, l.color)), "{name}");
-        }
-    }
-}

crates/render/src/viewports.rs

@@ -5,9 +5,7 @@ use super::draw::entity;
 #[cfg(not(target_arch = "wasm32"))]
 use super::pipeline::PARALLEL_CHUNK;
 use super::pipeline::{Options, style_table, top_ctx, with_point_view};
-use super::{
-    Bounds2, Builder, Ctx, Drawing, Entity, EntityKind, Handle, LayerIndex, MAX_BLOCK_EXPANSION, Mat3, Pen, Space, Vec2, clip, paper, pen, plotstyle,
-};
+use super::{Bounds2, Builder, Ctx, Drawing, Entity, EntityKind, Handle, MAX_BLOCK_EXPANSION, Mat3, Pen, Space, Vec2, clip, paper, pen, plotstyle};
 
 /// Upper bound on viewports drawn per layout (hostile files).
 pub(crate) const MAX_VIEWPORTS: usize = 256;
@@ -23,7 +21,7 @@ pub(crate) fn viewport(b: &mut Builder, d: &Drawing, e: &Entity, vp: &cadcraft_d
     let poly = viewport_clip(d, e.handle, vp);
     // Border (on the viewport's layer; layer off hides only the border).
     if poly.is_none() {
-        entity(b, &top_ctx(d, b.layers, Mat3::IDENTITY, e.handle, &[], &[]), e);
+        entity(b, &top_ctx(d, Mat3::IDENTITY, e.handle, &[], &[]), e);
     }
     if b.opts.skip_viewport == Some(e.handle) {
         return;
@@ -69,17 +67,8 @@ pub fn viewport_content(d: &Drawing, space: &Space, handle: Handle, area: Bounds
     }
     let opts = &with_point_view(d, space, opts);
     let styler = style_table(d, space, opts, false).map(|t| plotstyle::Styler::new(d, t));
-    let layers = LayerIndex::new(d);
-    let mut b = Builder {
-        list: DisplayList::default(),
-        opts,
-        plotting: false,
-        styles: styler.as_ref(),
-        named: None,
-        shared_budget: None,
-        transparency: 0,
-        layers: &layers,
-    };
+    let mut b =
+        Builder { list: DisplayList::default(), opts, plotting: false, styles: styler.as_ref(), named: None, shared_budget: None, transparency: 0 };
     contents(&mut b, d, vp, area, &Clip::Rect(area), paper::unit_mm_of(d, handle));
     b.list
 }
@@ -108,8 +97,7 @@ fn contents(b: &mut Builder, d: &Drawing, vp: &cadcraft_doc::Viewport, area: Bou
     // PSLTSCALE on: model-space dashes are scaled so they measure the same on paper as in
     // paper space, whatever the viewport scale.
     let lt_factor = if d.header.i64("PSLTSCALE", 1) != 0 { 1.0 / s } else { 1.0 };
-    let layers = b.layers;
-    let ctx = || Ctx { lt_factor, ..top_ctx(d, layers, xf, VIEWPORT_CONTENT, &vp.frozen_layers, &vp.layer_colors) };
+    let ctx = || Ctx { lt_factor, ..top_ctx(d, xf, VIEWPORT_CONTENT, &vp.frozen_layers, &vp.layer_colors) };
     let seen = |me: &Entity| {
         if matches!(me.kind, EntityKind::Viewport(_)) {
             return false;
@@ -132,7 +120,6 @@ fn contents(b: &mut Builder, d: &Drawing, vp: &cadcraft_doc::Viewport, area: Bou
         named: None,
         shared_budget: Some(&budget),
         transparency: 0,
-        layers,
     };
     #[cfg(not(target_arch = "wasm32"))]
     let parallel = !b.plotting && b.styles.is_none() && d.model.len() >= 2 * PARALLEL_CHUNK;
@@ -156,7 +143,6 @@ fn contents(b: &mut Builder, d: &Drawing, vp: &cadcraft_doc::Viewport, area: Bou
                         named: None,
                         shared_budget: Some(&budget),
                         transparency: 0,
-                        layers,
                     };
                     let c = ctx();
                     for me in chunk.iter().filter(|me| seen(me)) {