address review: charge empty curves only in snap_ends search

crates/constraints/src/auto.rs

@@ -232,6 +232,10 @@ pub fn infer_placed(d: &Drawing, placed: &[Handle], others: &[Handle], o: &Infer
     let mut extra = Vec::new();
     let mut on = Vec::new();
     for (rp, p) in g.points.iter().filter(|(r, _)| placed.contains(&r.handle)) {
+        // Nothing is added once the candidates are full, so the points left need no search.
+        if extra.len() + on.len() + out.len() >= MAX_CANDIDATES {
+            break;
+        }
         if out.iter().any(|c| c.kind == ConstraintKind::Coincident && c.refs.contains(rp)) {
             continue;
         }
@@ -267,20 +271,22 @@ pub fn infer_placed(d: &Drawing, placed: &[Handle], others: &[Handle], o: &Infer
     // Perpendicular lines meeting in a T (a perpendicular snap onto the middle of a line).
     let atol = if o.angle_tolerance.is_finite() { o.angle_tolerance.clamp(0.0, 45.0).to_radians() } else { 0.0 };
     let allow_per = o.types.is_empty() || o.types.iter().any(|t| t.eq_ignore_ascii_case(ConstraintKind::Perpendicular.name()));
-    for (r1, a1, b1) in g.lines.iter().filter(|(r, _, _)| placed.contains(&r.handle)) {
+    'per: for (r1, a1, b1) in g.lines.iter().filter(|(r, _, _)| allow_per && placed.contains(&r.handle)) {
         for (r2, a2, b2) in g.lines.iter().filter(|(r, _, _)| r.handle != r1.handle) {
+            // Full: nothing more can be added, so the pairs left need no geometry or duplicate search.
+            if out.len() >= MAX_CANDIDATES {
+                break 'per;
+            }
             let (l1, l2) = (Line::new(*a1, *b1), Line::new(*a2, *b2));
             let touches = |l: &Line, p: Vec2| l.dist(p) <= tol && (0.0..=1.0).contains(&l.param_of(p));
             let tee = [*a1, *b1].iter().any(|p| touches(&l2, *p)) || [*a2, *b2].iter().any(|p| touches(&l1, *p));
             let ang = ang_between(*b1 - *a1, *b2 - *a2);
-            let dup = out.iter().any(|c| c.kind == ConstraintKind::Perpendicular && c.refs.contains(r1) && c.refs.contains(r2));
-            if allow_per
-                && tee
-                && !dup
+            // The duplicate search scans every candidate, so it comes after the cheap tests.
+            if tee
                 && (std::f64::consts::FRAC_PI_2 - ang).abs() <= atol
                 && l1.len() > tol
                 && l2.len() > tol
-                && out.len() < MAX_CANDIDATES
+                && !out.iter().any(|c| c.kind == ConstraintKind::Perpendicular && c.refs.contains(r1) && c.refs.contains(r2))
             {
                 out.push(Constraint { id: 0, kind: ConstraintKind::Perpendicular, refs: vec![*r1, *r2], name: String::new(), expr: String::new() });
             }

crates/fonts/src/ttf.rs

@@ -89,7 +89,11 @@ impl Face {
         let Some(f) = self.font() else { return Vec::new() };
         [skrifa::string::StringId::FAMILY_NAME, skrifa::string::StringId::TYPOGRAPHIC_FAMILY_NAME, skrifa::string::StringId::FULL_NAME]
             .into_iter()
-            .flat_map(|id| f.localized_strings(id).map(|s| norm(&s.to_string())).collect::<Vec<_>>())
+            // A name table can hold many records that point at one big string: at most
+            // MAX_NAME_RECORDS per name id, each decoded only up to MAX_NAME_CHARS characters.
+            .flat_map(|id| {
+                f.localized_strings(id).take(MAX_NAME_RECORDS).map(|s| norm(&s.chars().take(MAX_NAME_CHARS).collect::<String>())).collect::<Vec<_>>()
+            })
             .collect()
     }
 }
@@ -104,6 +108,10 @@ pub fn faces(bytes: &Arc<Vec<u8>>) -> Vec<Face> {
 }
 
 const MAX_FACES_PER_FILE: u32 = 32;
+/// Name records read per name id of a face, and characters read of each: real fonts have a few
+/// dozen short ones.
+const MAX_NAME_RECORDS: usize = 64;
+const MAX_NAME_CHARS: usize = 256;
 /// Bounds of the missing-glyph search: files loaded, bytes loaded, faces checked per character.
 const MAX_FALLBACK_FILES: usize = 24;
 const MAX_FALLBACK_BYTES: usize = 160 << 20;

crates/geom/src/region.rs

@@ -110,6 +110,10 @@ fn build(polys: &[Vec<Vec2>], tol: f64) -> Option<Graph> {
     };
     let mut grid: HashMap<(usize, usize), Vec<usize>> = HashMap::new();
     let mut long: Vec<usize> = Vec::new();
+    // Every cell a segment is registered in is an index kept: past this many in all (each segment
+    // may take up to 4096 cells), the input is refused as it is for too much pair work.
+    const MAX_REGISTRATIONS: usize = 20_000_000;
+    let mut registered = 0usize;
     for (i, (a, b)) in segs.iter().enumerate() {
         let (x0, y0) = cell(a.min(*b));
         let (x1, y1) = cell(a.max(*b));
@@ -118,6 +122,10 @@ fn build(polys: &[Vec<Vec2>], tol: f64) -> Option<Graph> {
             long.push(i);
             continue;
         }
+        registered = registered.saturating_add((x1 - x0 + 1) * (y1 - y0 + 1));
+        if registered > MAX_REGISTRATIONS {
+            return None;
+        }
         for gx in x0..=x1 {
             for gy in y0..=y1 {
                 grid.entry((gx, gy)).or_default().push(i);
@@ -424,19 +432,32 @@ fn islands(g: &Graph, outer: &[usize], p: Vec2) -> Vec<Island> {
     let mut starts: Vec<(usize, usize)> = start.into_iter().collect();
     starts.sort_unstable();
     let mut out = Vec::new();
+    // Each containment test scans a whole polygon, accepted or not: they share one allowance of
+    // polygon edges, and the search ends when it is spent.
+    let mut edges_left: usize = 100_000_000;
     for (c, u) in starts {
         if out.len() >= MAX_ISLANDS {
             break;
         }
         let Some(&pu) = core.pts.get(u) else { continue };
-        if !ob.contains(pu) || !point_in_polygon(&outer_pts, pu) {
+        if !ob.contains(pu) {
+            continue;
+        }
+        let Some(left) = edges_left.checked_sub(outer_pts.len()) else { break };
+        edges_left = left;
+        if !point_in_polygon(&outer_pts, pu) {
             continue;
         }
         let steps = edges.get(&c).copied().unwrap_or(0).saturating_add(4);
         let Some(lp) = outside(&core, u, steps) else { continue };
         let area = shoelace(&lp);
         let ib = Bounds2::from_points(lp.iter().copied());
-        if lp.len() < 3 || !area.is_finite() || area <= 0.0 || !ob.contains_box(&ib) || point_in_polygon(&lp, p) {
+        if lp.len() < 3 || !area.is_finite() || area <= 0.0 || !ob.contains_box(&ib) {
+            continue;
+        }
+        let Some(left) = edges_left.checked_sub(lp.len()) else { break };
+        edges_left = left;
+        if point_in_polygon(&lp, p) {
             continue;
         }
         let mut src = sources.remove(&c).unwrap_or_default();
@@ -457,6 +478,10 @@ fn nearest_curve(polys: &[Vec<Vec2>], i: usize, e: Vec2, snap: f64, tol: f64, bu
         if j == i {
             continue;
         }
+        // A curve with no segment costs a visit too, so many of them can't multiply the searches.
+        if other.len() < 2 {
+            *budget = budget.checked_sub(1).ok_or(())?;
+        }
         for (k, w) in other.windows(2).enumerate() {
             if *budget == 0 {
                 return Err(());