refactor(scene/mod.rs): pull entity-specific helpers into entities/

Five chunks moved out of the 5965-line scene/mod.rs to live with the
entities they belong to:

- wide_lwpolyline_fills → entities/lwpolyline.rs::wide_fills
- wide_polyline2d_fills → entities/polyline.rs::wide_fills
- polyline_segment_fill → entities/common.rs (shared by both above)
- text_obb_corners_native + text_baseline_points + text_greek_obb_tris
  → entities/text_support.rs (handles Text/MText/Attribute alike)
- append_insert_attribute_wires → entities/insert.rs

Net: scene/mod.rs 5965 → 5404 lines (~560 lines extracted). Three
helpers in scene/render.rs / scene/block_cache.rs widened from
pub(super) to pub(crate) so the relocated functions can still reach
them. scene::entity_aabb also widened for the same reason.

scene::tessellate_entity_dim_text stays put — it's a thin wrapper
around the private tessellate_entity dispatcher and moving it would
require exposing tessellate_entity's full signature across the crate.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/entities/common.rs

@@ -167,3 +167,84 @@ pub fn ro_prop(label: &'static str, field: &'static str, value: impl Into<String
 pub fn parse_f64(value: &str) -> Option<f64> {
     value.trim().parse::<f64>().ok()
 }
+/// Compute the filled boundary polygon for one polyline segment.
+/// For straight segments: a rectangle/trapezoid.
+/// For arc segments: an arc band (outer arc + reversed inner arc).
+/// Returns `None` if the segment is degenerate.
+pub(crate) fn polyline_segment_fill(
+    p0: [f32; 2],
+    p1: [f32; 2],
+    hw0: f32,
+    hw1: f32,
+    bulge: f32,
+) -> Option<Vec<[f32; 2]>> {
+    if bulge.abs() < 1e-9 {
+        // Straight segment — rectangle or trapezoid
+        let dx = p1[0] - p0[0];
+        let dy = p1[1] - p0[1];
+        let len = (dx * dx + dy * dy).sqrt();
+        if len < 1e-9 {
+            return None;
+        }
+        let nx = -dy / len;
+        let ny = dx / len;
+        Some(vec![
+            [p0[0] + hw0 * nx, p0[1] + hw0 * ny],
+            [p1[0] + hw1 * nx, p1[1] + hw1 * ny],
+            [p1[0] - hw1 * nx, p1[1] - hw1 * ny],
+            [p0[0] - hw0 * nx, p0[1] - hw0 * ny],
+        ])
+    } else {
+        // Arc segment — arc band polygon.
+        // Center math matches `bulge_to_arc` in modules/home/modify/explode.rs:
+        //   r = chord * (1 + b²) / (4·|b|)
+        //   d = r * (1 - b²) / (1 + b²)   (signed: negative ⇒ major arc, center
+        //                                  flips to the opposite side of chord)
+        //   center = midpoint + sign(b) · d · left_perp(chord)
+        let b = bulge as f64;
+        let b2 = b * b;
+        let dx = (p1[0] - p0[0]) as f64;
+        let dy = (p1[1] - p0[1]) as f64;
+        let chord_len = (dx * dx + dy * dy).sqrt();
+        if chord_len < 1e-9 || b.abs() < 1e-12 {
+            return None;
+        }
+        let r = chord_len * (1.0 + b2) / (4.0 * b.abs());
+        let d_perp = r * (1.0 - b2) / (1.0 + b2);
+        let mx = ((p0[0] + p1[0]) * 0.5) as f64;
+        let my = ((p0[1] + p1[1]) * 0.5) as f64;
+        let perp_x = -dy / chord_len;
+        let perp_y = dx / chord_len;
+        let sign = b.signum();
+        let cx = (mx + sign * d_perp * perp_x) as f32;
+        let cy = (my + sign * d_perp * perp_y) as f32;
+        let a0 = ((p0[1] - cy) as f32).atan2((p0[0] - cx) as f32);
+        let a1 = ((p1[1] - cy) as f32).atan2((p1[0] - cx) as f32);
+        let (sa, mut ea) = if bulge > 0.0 { (a0, a1) } else { (a1, a0) };
+        if ea < sa {
+            ea += std::f32::consts::TAU;
+        }
+        let span = ea - sa;
+        let segs = ((span.abs() / std::f32::consts::TAU) * 24.0)
+            .ceil()
+            .max(4.0) as u32;
+        let r = r as f32;
+        let r_outer = |t: f32| r + (hw0 + (hw1 - hw0) * t);
+        let r_inner = |t: f32| (r - (hw0 + (hw1 - hw0) * t)).max(0.0);
+        let mut boundary = Vec::with_capacity((segs as usize + 1) * 2);
+        let inv = 1.0 / segs as f32;
+        for j in 0..=segs {
+            let t = j as f32 * inv;
+            let ang = sa + span * t;
+            let ro = r_outer(t);
+            boundary.push([cx + ro * ang.cos(), cy + ro * ang.sin()]);
+        }
+        for j in (0..=segs).rev() {
+            let t = j as f32 * inv;
+            let ang = sa + span * t;
+            let ri = r_inner(t);
+            boundary.push([cx + ri * ang.cos(), cy + ri * ang.sin()]);
+        }
+        Some(boundary)
+    }
+}

src/entities/insert.rs

@@ -1,11 +1,14 @@
 use acadrust::entities::Insert;
 use acadrust::types::{Transform, Vector3};
+use acadrust::{EntityType, Handle};
 use glam::Vec3;
 
 use crate::command::EntityTransform;
 use crate::entities::common::{edit_prop as edit, parse_f64, ro_prop as ro, square_grip};
 use crate::entities::traits::{Grippable, PropertyEditable, Transformable};
 use crate::scene::object::{GripApply, GripDef, PropSection};
+use crate::scene::{block_cache, render, tessellate};
+use crate::scene::wire_model::WireModel;
 
 fn grips(ins: &Insert) -> Vec<GripDef> {
     let p = Vec3::new(
@@ -142,3 +145,75 @@ impl crate::entities::traits::FallbackTess for Insert {
         )
     }
 }
+pub(crate) fn append_insert_attribute_wires(
+    wires: &mut Vec<WireModel>,
+    document: &acadrust::CadDocument,
+    ins: &acadrust::entities::Insert,
+    insert_handle: Handle,
+    sel: bool,
+    ins_color: [f32; 4],
+    ins_pat_len: f32,
+    ins_pat: [f32; 8],
+    ins_lw_px: f32,
+    bg_color: [f32; 4],
+    is_xref: bool,
+    pslt_factor: f32,
+    anno_scale: f32,
+    world_offset: [f64; 3],
+) {
+    if ins.attributes.is_empty() {
+        return;
+    }
+    // ATTMODE (header.attribute_visibility):
+    //   0 = Off    — every attribute hidden
+    //   1 = Normal — honour per-attribute `invisible` flag (default)
+    //   2 = On     — every attribute forced visible, ignoring its flag
+    let attmode = document.header.attribute_visibility;
+    if attmode == 0 {
+        return;
+    }
+    for attr in &ins.attributes {
+        let per_attr_hidden = attr.common.invisible || attr.flags.invisible;
+        if attmode == 1 && per_attr_hidden {
+            continue;
+        }
+        let attr_entity = EntityType::AttributeEntity(attr.clone());
+        let (sub_color, sub_plen, sub_pat, sub_lw_px, sub_aci) =
+            render::render_style_for_block_sub(
+                document,
+                &attr_entity,
+                ins_color,
+                ins_pat_len,
+                ins_pat,
+                ins_lw_px,
+            );
+        let sub_color = render::adapt_to_bg(sub_color, bg_color);
+        let sub_color = if is_xref && !sel {
+            block_cache::fade_toward_bg(sub_color, bg_color)
+        } else {
+            sub_color
+        };
+        let sub_aabb = crate::scene::entity_aabb(&attr_entity, world_offset);
+        let mut attr_wires = tessellate::tessellate(
+            document,
+            insert_handle,
+            &attr_entity,
+            sel,
+            sub_color,
+            sub_plen * pslt_factor,
+            sub_pat.map(|v| v * pslt_factor),
+            sub_lw_px,
+            world_offset,
+            anno_scale,
+        );
+        // Use the INSERT's handle so selection / picking groups attribute
+        // text with the parent insert instead of treating it as a stray text.
+        for w in &mut attr_wires {
+            w.name = insert_handle.value().to_string();
+            w.aci = sub_aci;
+            w.aabb = sub_aabb;
+        }
+        wires.extend(attr_wires);
+    }
+}
+

src/entities/lwpolyline.rs

@@ -516,3 +516,36 @@ impl Transformable for LwPolyline {
         apply_transform(self, t);
     }
 }
+pub(crate) fn wide_fills(pl: &acadrust::entities::LwPolyline) -> Vec<Vec<[f32; 2]>> {
+    let hw_const = (pl.constant_width / 2.0) as f32;
+    let verts = &pl.vertices;
+    let n = verts.len();
+    if n < 2 {
+        return vec![];
+    }
+    let seg_count = if pl.is_closed { n } else { n - 1 };
+    let mut out = Vec::new();
+    for i in 0..seg_count {
+        let v0 = &verts[i];
+        let v1 = &verts[(i + 1) % n];
+        let hw0 = if v0.start_width > 1e-9 {
+            v0.start_width as f32 / 2.0
+        } else {
+            hw_const
+        };
+        let hw1 = if v0.end_width > 1e-9 {
+            v0.end_width as f32 / 2.0
+        } else {
+            hw_const
+        };
+        if hw0 < 1e-6 && hw1 < 1e-6 {
+            continue;
+        }
+        let p0 = [v0.location.x as f32, v0.location.y as f32];
+        let p1 = [v1.location.x as f32, v1.location.y as f32];
+        if let Some(poly) = crate::entities::common::polyline_segment_fill(p0, p1, hw0, hw1, v0.bulge as f32) {
+            out.push(poly);
+        }
+    }
+    out
+}

src/entities/polyline.rs

@@ -596,3 +596,37 @@ impl Transformable for Polyline3D {
         });
     }
 }
+/// Generate solid-fill boundary polygons for each wide segment of a Polyline2D.
+pub(crate) fn wide_fills(pl: &acadrust::entities::Polyline2D) -> Vec<Vec<[f32; 2]>> {
+    let hw_default = (pl.start_width.max(pl.end_width) / 2.0) as f32;
+    let verts = &pl.vertices;
+    let n = verts.len();
+    if n < 2 {
+        return vec![];
+    }
+    let seg_count = if pl.is_closed() { n } else { n - 1 };
+    let mut out = Vec::new();
+    for i in 0..seg_count {
+        let v0 = &verts[i];
+        let v1 = &verts[(i + 1) % n];
+        let hw0 = if v0.start_width > 1e-9 {
+            v0.start_width as f32 / 2.0
+        } else {
+            hw_default
+        };
+        let hw1 = if v0.end_width > 1e-9 {
+            v0.end_width as f32 / 2.0
+        } else {
+            hw_default
+        };
+        if hw0 < 1e-6 && hw1 < 1e-6 {
+            continue;
+        }
+        let p0 = [v0.location.x as f32, v0.location.y as f32];
+        let p1 = [v1.location.x as f32, v1.location.y as f32];
+        if let Some(poly) = crate::entities::common::polyline_segment_fill(p0, p1, hw0, hw1, v0.bulge as f32) {
+            out.push(poly);
+        }
+    }
+    out
+}

src/entities/text_support.rs

@@ -1,5 +1,5 @@
 use acadrust::types::aci_table::aci_to_rgb;
-use acadrust::CadDocument;
+use acadrust::{CadDocument, EntityType};
 
 use crate::scene::acad_to_truck::TextStroke;
 use crate::scene::cxf;
@@ -1364,3 +1364,334 @@ pub fn layout_mtext(opts: &MTextRenderOpts) -> MTextLayout {
         v_offset,
     }
 }
+pub(crate) fn text_obb_corners_native(
+    e: &EntityType,
+    anno_scale: f32,
+    mtext_lines_override: Option<usize>,
+) -> Option<[[f64; 3]; 4]> {
+    use acadrust::entities::attribute_definition::{
+        HorizontalAlignment as AttrHA, VerticalAlignment as AttrVA,
+    };
+    use acadrust::entities::{AttachmentPoint, TextHorizontalAlignment, TextVerticalAlignment};
+
+    let anno = anno_scale as f64;
+
+    // Map Attribute alignment enums to the same h/v anchor fractions used by
+    // Text. Kept local because the Attribute enum is distinct from Text's.
+    let attr_h_anchor = |ha: AttrHA| -> f64 {
+        match ha {
+            AttrHA::Left => 0.0,
+            AttrHA::Center | AttrHA::Middle | AttrHA::Aligned | AttrHA::Fit => 0.5,
+            AttrHA::Right => 1.0,
+        }
+    };
+    let attr_v_anchor = |va: AttrVA| -> f64 {
+        match va {
+            AttrVA::Baseline | AttrVA::Bottom => 0.0,
+            AttrVA::Middle => 0.5,
+            AttrVA::Top => 1.0,
+        }
+    };
+    let attr_use_align_pt = |ha: AttrHA, va: AttrVA| -> bool {
+        !matches!((ha, va), (AttrHA::Left, AttrVA::Baseline))
+    };
+
+    let (ix, iy, iz, w, h, rot, h_anchor, v_anchor) = match e {
+        EntityType::Text(t) => {
+            let h_world = t.height * anno;
+            let w_factor = if t.width_factor > 0.0 { t.width_factor } else { 1.0 };
+            let n = t.value.chars().count().max(1) as f64;
+            // Approximate glyph width: AutoCAD's stroke fonts average ~0.6 em.
+            let w_world = n * h_world * w_factor * 0.6;
+            let h_anchor = match t.horizontal_alignment {
+                TextHorizontalAlignment::Left => 0.0,
+                TextHorizontalAlignment::Center
+                | TextHorizontalAlignment::Middle
+                | TextHorizontalAlignment::Aligned
+                | TextHorizontalAlignment::Fit => 0.5,
+                TextHorizontalAlignment::Right => 1.0,
+            };
+            let v_anchor = match t.vertical_alignment {
+                TextVerticalAlignment::Baseline | TextVerticalAlignment::Bottom => 0.0,
+                TextVerticalAlignment::Middle => 0.5,
+                TextVerticalAlignment::Top => 1.0,
+            };
+            // AutoCAD writes `alignment_point` (DXF 11) whenever the text
+            // isn't simple Left+Baseline; in that case it — not the
+            // insertion_point — is the anchor the alignment fractions map to.
+            let use_alignment_pt = !matches!(
+                (t.horizontal_alignment, t.vertical_alignment),
+                (
+                    TextHorizontalAlignment::Left,
+                    TextVerticalAlignment::Baseline,
+                )
+            );
+            let anchor = match (use_alignment_pt, t.alignment_point) {
+                (true, Some(p)) => p,
+                _ => t.insertion_point,
+            };
+            (
+                anchor.x,
+                anchor.y,
+                anchor.z,
+                w_world,
+                h_world,
+                t.rotation,
+                h_anchor,
+                v_anchor,
+            )
+        }
+        EntityType::AttributeDefinition(a) => {
+            let h_world = a.height * anno;
+            let w_factor = if a.width_factor > 0.0 { a.width_factor } else { 1.0 };
+            // Render the tag in preview when no default; matches `attribute.rs`.
+            let display = if a.default_value.is_empty() { &a.tag } else { &a.default_value };
+            let n = display.chars().count().max(1) as f64;
+            let w_world = n * h_world * w_factor * 0.6;
+            let h_anchor = attr_h_anchor(a.horizontal_alignment);
+            let v_anchor = attr_v_anchor(a.vertical_alignment);
+            let anchor = if attr_use_align_pt(a.horizontal_alignment, a.vertical_alignment) {
+                a.alignment_point
+            } else {
+                a.insertion_point
+            };
+            (
+                anchor.x, anchor.y, anchor.z, w_world, h_world, a.rotation, h_anchor, v_anchor,
+            )
+        }
+        EntityType::AttributeEntity(a) => {
+            let h_world = a.height * anno;
+            let w_factor = if a.width_factor > 0.0 { a.width_factor } else { 1.0 };
+            let n = a.value.chars().count().max(1) as f64;
+            let w_world = n * h_world * w_factor * 0.6;
+            let h_anchor = attr_h_anchor(a.horizontal_alignment);
+            let v_anchor = attr_v_anchor(a.vertical_alignment);
+            let anchor = if attr_use_align_pt(a.horizontal_alignment, a.vertical_alignment) {
+                a.alignment_point
+            } else {
+                a.insertion_point
+            };
+            (
+                anchor.x, anchor.y, anchor.z, w_world, h_world, a.rotation, h_anchor, v_anchor,
+            )
+        }
+        EntityType::Tolerance(t) => {
+            // Approximate: a feature control frame is roughly 1 line tall;
+            // width comes from char-count of the (already-stripped) text.
+            // GD&T symbols all advance one cell, so plain char count is close.
+            let raw_h = if t.text_height > 0.0 { t.text_height } else { 2.5 };
+            let h_world = raw_h * anno;
+            // Each cell ≈ 1.4 × height (matches `tolerance.rs` min_cell_w).
+            let n = t.text.chars().filter(|c| *c != '\n').count().max(1) as f64;
+            let w_world = h_world * 1.4 * n * 0.5; // rough — fine for LOD greek
+            // direction encodes rotation as a vector.
+            let rot = (t.direction.y).atan2(t.direction.x);
+            (
+                t.insertion_point.x,
+                t.insertion_point.y,
+                t.insertion_point.z,
+                w_world,
+                h_world * 1.5, // frame is taller than glyph cap by ~0.5 h
+                rot,
+                0.0, // anchored at insertion point (bottom-left)
+                0.0,
+            )
+        }
+        EntityType::MText(m) => {
+            let h_world = m.height * anno;
+            let raw_lines = (m.value.matches('\n').count() + 1) as f64;
+            let effective_lines = match mtext_lines_override {
+                Some(n) => n.max(1) as f64,
+                None => raw_lines,
+            };
+            let w_world = if m.rectangle_width > 0.0 {
+                m.rectangle_width
+            } else {
+                h_world * 8.0 * effective_lines.max(1.0)
+            };
+            // Wrap-aware override beats `rectangle_height` — the stored
+            // height can be stale on DWGs that were re-saved without
+            // updating the bounds.
+            let total_h = if mtext_lines_override.is_some() {
+                h_world * effective_lines.max(1.0) * m.line_spacing_factor.max(0.5)
+            } else {
+                m.rectangle_height.unwrap_or(
+                    h_world * raw_lines.max(1.0) * m.line_spacing_factor.max(0.5),
+                )
+            };
+            // MText `attachment_point` puts `insertion_point` at one of the
+            // 9 corners/midpoints of the text bbox. h_anchor / v_anchor are
+            // fractions from (left, bottom) of the bbox.
+            let (h_anchor, v_anchor) = match m.attachment_point {
+                AttachmentPoint::TopLeft => (0.0, 1.0),
+                AttachmentPoint::TopCenter => (0.5, 1.0),
+                AttachmentPoint::TopRight => (1.0, 1.0),
+                AttachmentPoint::MiddleLeft => (0.0, 0.5),
+                AttachmentPoint::MiddleCenter => (0.5, 0.5),
+                AttachmentPoint::MiddleRight => (1.0, 0.5),
+                AttachmentPoint::BottomLeft => (0.0, 0.0),
+                AttachmentPoint::BottomCenter => (0.5, 0.0),
+                AttachmentPoint::BottomRight => (1.0, 0.0),
+            };
+            (
+                m.insertion_point.x,
+                m.insertion_point.y,
+                m.insertion_point.z,
+                w_world,
+                total_h,
+                m.rotation,
+                h_anchor,
+                v_anchor,
+            )
+        }
+        _ => return None,
+    };
+
+    let x0 = -h_anchor * w;
+    let x1 = (1.0 - h_anchor) * w;
+    let y0 = -v_anchor * h;
+    let y1 = (1.0 - v_anchor) * h;
+
+    let (s, c) = (rot.sin(), rot.cos());
+    let rot_pt = |lx: f64, ly: f64| -> [f64; 3] {
+        let rx = lx * c - ly * s;
+        let ry = lx * s + ly * c;
+        [ix + rx, iy + ry, iz]
+    };
+
+    Some([
+        rot_pt(x0, y0),
+        rot_pt(x1, y0),
+        rot_pt(x1, y1),
+        rot_pt(x0, y1),
+    ])
+}
+pub(crate) fn text_baseline_points(
+    e: &EntityType,
+    anno_scale: f32,
+    world_offset: [f64; 3],
+    n_lines: usize,
+) -> Vec<[f32; 3]> {
+    let Some(corners) = text_obb_corners_native(e, anno_scale, Some(n_lines)) else {
+        return vec![];
+    };
+    let line_h = match e {
+        EntityType::Text(t) => (t.height * anno_scale as f64) as f32,
+        EntityType::MText(m) => (m.height * anno_scale as f64) as f32,
+        EntityType::AttributeDefinition(a) => (a.height * anno_scale as f64) as f32,
+        EntityType::AttributeEntity(a) => (a.height * anno_scale as f64) as f32,
+        EntityType::Tolerance(t) => {
+            let raw = if t.text_height > 0.0 { t.text_height } else { 2.5 };
+            (raw * anno_scale as f64) as f32
+        }
+        _ => return vec![],
+    };
+    if line_h <= 0.0 {
+        return vec![];
+    }
+    let n_lines = n_lines.max(1);
+    let [ox, oy, oz] = world_offset;
+    let cast = |p: [f64; 3]| -> [f32; 3] {
+        [(p[0] - ox) as f32, (p[1] - oy) as f32, (p[2] - oz) as f32]
+    };
+    let bl = cast(corners[0]);
+    let br = cast(corners[1]);
+    let full_tl = cast(corners[3]);
+
+    let (ux, uy, uz) = (full_tl[0] - bl[0], full_tl[1] - bl[1], full_tl[2] - bl[2]);
+    let ulen = (ux * ux + uy * uy + uz * uz).sqrt();
+    if ulen < 1e-9 {
+        return vec![bl, br];
+    }
+    let (nx, ny, nz) = (ux / ulen, uy / ulen, uz / ulen);
+
+    let mut pts = Vec::with_capacity(n_lines * 3);
+    for i in 0..n_lines {
+        // i = 0 is the topmost line — its bottom sits one line_h below
+        // the OBB top (≈ `ulen`). For n_lines > ulen/line_h the deepest
+        // baselines clamp to the OBB bottom.
+        let bot_off = ((i + 1) as f32) * line_h;
+        let along = (ulen - bot_off).max(0.0);
+        let p0 = [bl[0] + nx * along, bl[1] + ny * along, bl[2] + nz * along];
+        let p1 = [br[0] + nx * along, br[1] + ny * along, br[2] + nz * along];
+        if !pts.is_empty() {
+            pts.push([f32::NAN; 3]);
+        }
+        pts.extend_from_slice(&[p0, p1]);
+    }
+    pts
+}
+
+/// Filled tris for a greeked top-level Text / MText. One 2-triangle rect
+/// per visible line — `n_lines` is the actual rendered line count from
+/// `mtext_line_count` (1 for Text). Stacked top → bottom along the OBB's
+/// up direction. The face3d pipeline skips its 0.45 dim for wires with
+/// empty `points`, so these tris render at the literal text color.
+pub(crate) fn text_greek_obb_tris(
+    e: &EntityType,
+    anno_scale: f32,
+    world_offset: [f64; 3],
+    n_lines: usize,
+) -> Vec<[f32; 3]> {
+    let Some(corners) = text_obb_corners_native(e, anno_scale, Some(n_lines)) else {
+        return vec![];
+    };
+    let line_h = match e {
+        EntityType::Text(t) => (t.height * anno_scale as f64) as f32,
+        EntityType::MText(m) => (m.height * anno_scale as f64) as f32,
+        EntityType::AttributeDefinition(a) => (a.height * anno_scale as f64) as f32,
+        EntityType::AttributeEntity(a) => (a.height * anno_scale as f64) as f32,
+        EntityType::Tolerance(t) => {
+            let raw = if t.text_height > 0.0 { t.text_height } else { 2.5 };
+            (raw * anno_scale as f64) as f32
+        }
+        _ => return vec![],
+    };
+    if line_h <= 0.0 {
+        return vec![];
+    }
+    let n_lines = n_lines.max(1);
+    let [ox, oy, oz] = world_offset;
+    let cast = |p: [f64; 3]| -> [f32; 3] {
+        [(p[0] - ox) as f32, (p[1] - oy) as f32, (p[2] - oz) as f32]
+    };
+    let bl = cast(corners[0]);
+    let br = cast(corners[1]);
+    let full_tl = cast(corners[3]);
+
+    let (ux, uy, uz) = (full_tl[0] - bl[0], full_tl[1] - bl[1], full_tl[2] - bl[2]);
+    let ulen = (ux * ux + uy * uy + uz * uz).sqrt();
+    if ulen < 1e-9 {
+        return vec![];
+    }
+    let (nx, ny, nz) = (ux / ulen, uy / ulen, uz / ulen);
+
+    let mut tris = Vec::with_capacity(n_lines * 6);
+    for i in 0..n_lines {
+        let top_along = (ulen - (i as f32) * line_h).max(0.0);
+        let bot_along = (ulen - ((i + 1) as f32) * line_h).max(0.0);
+        let tl = [
+            bl[0] + nx * top_along,
+            bl[1] + ny * top_along,
+            bl[2] + nz * top_along,
+        ];
+        let tr = [
+            br[0] + nx * top_along,
+            br[1] + ny * top_along,
+            br[2] + nz * top_along,
+        ];
+        let lbl = [
+            bl[0] + nx * bot_along,
+            bl[1] + ny * bot_along,
+            bl[2] + nz * bot_along,
+        ];
+        let lbr = [
+            br[0] + nx * bot_along,
+            br[1] + ny * bot_along,
+            br[2] + nz * bot_along,
+        ];
+        tris.extend_from_slice(&[lbl, lbr, tr, lbl, tr, tl]);
+    }
+    tris
+}
+

src/scene/block_cache.rs

@@ -456,7 +456,7 @@ fn tessellate_sub_local(
         _ => None,
     };
     let text_obb_local: Option<[[f32; 3]; 4]> =
-        crate::scene::text_obb_corners_native(sub, anno_scale, mtext_lines).map(|c| {
+        crate::entities::text_support::text_obb_corners_native(sub, anno_scale, mtext_lines).map(|c| {
             [
                 [(c[0][0] - lo_x) as f32, (c[0][1] - lo_y) as f32, (c[0][2] - lo_z) as f32],
                 [(c[1][0] - lo_x) as f32, (c[1][1] - lo_y) as f32, (c[1][2] - lo_z) as f32],
@@ -941,7 +941,7 @@ struct ExpandCtx<'a> {
 /// Fade `color` toward `bg` by 50%, preserving alpha. Used to mark xref
 /// geometry — the hue stays recognizable but the contrast against the
 /// background drops, reading as "washed out".
-pub(super) fn fade_toward_bg(color: [f32; 4], bg: [f32; 4]) -> [f32; 4] {
+pub(crate) fn fade_toward_bg(color: [f32; 4], bg: [f32; 4]) -> [f32; 4] {
     const T: f32 = 0.5;
     [
         color[0] * (1.0 - T) + bg[0] * T,

src/scene/mod.rs

@@ -2637,8 +2637,8 @@ impl Scene {
         let oy = oy as f32;
         for entity in self.document.entities() {
             let (common, fills) = match entity {
-                EntityType::LwPolyline(pl) => (&pl.common, wide_lwpolyline_fills(pl)),
+                EntityType::LwPolyline(pl) => (&pl.common, crate::entities::lwpolyline::wide_fills(pl)),
-                EntityType::Polyline2D(pl) => (&pl.common, wide_polyline2d_fills(pl)),
+                EntityType::Polyline2D(pl) => (&pl.common, crate::entities::polyline::wide_fills(pl)),
                 _ => continue,
             };
             if fills.is_empty() {
@@ -5047,7 +5047,7 @@ fn tessellate_entity(
                 // the AttributeEntity instances live on the Insert itself in
                 // WCS and need their own tessellation so the user sees the
                 // values they actually filled in. See #20.
-                append_insert_attribute_wires(
+                crate::entities::insert::append_insert_attribute_wires(
                     &mut wires,
                     document,
                     ins,
@@ -5119,7 +5119,7 @@ fn tessellate_entity(
                 wires
             })
             .collect();
-        append_insert_attribute_wires(
+        crate::entities::insert::append_insert_attribute_wires(
             &mut wires,
             document,
             ins,
@@ -5176,7 +5176,7 @@ fn tessellate_entity(
                 _ => 1,
             };
             if h_px < 1.0 {
-                let pts = text_baseline_points(e, anno_scale, world_offset, n_lines);
+                let pts = crate::entities::text_support::text_baseline_points(e, anno_scale, world_offset, n_lines);
                 if pts.len() < 2 {
                     return vec![];
                 }
@@ -5218,7 +5218,7 @@ fn tessellate_entity(
                 }];
             }
             if h_px < 5.0 && aabb != WireModel::UNBOUNDED_AABB {
-                let fill_tris = text_greek_obb_tris(e, anno_scale, world_offset, n_lines);
+                let fill_tris = crate::entities::text_support::text_greek_obb_tris(e, anno_scale, world_offset, n_lines);
                 if fill_tris.is_empty() {
                     return vec![lod_stub_wire(
                         h.value().to_string(),
@@ -5309,208 +5309,6 @@ fn tessellate_entity(
 /// (from `text_support::mtext_line_count`). Without it, MText's OBB
 /// height collapses to a single line when the file omits `rectangle_height`,
 /// which makes downstream per-line LOD math degenerate.
-pub(crate) fn text_obb_corners_native(
-    e: &EntityType,
-    anno_scale: f32,
-    mtext_lines_override: Option<usize>,
-) -> Option<[[f64; 3]; 4]> {
-    use acadrust::entities::attribute_definition::{
-        HorizontalAlignment as AttrHA, VerticalAlignment as AttrVA,
-    };
-    use acadrust::entities::{AttachmentPoint, TextHorizontalAlignment, TextVerticalAlignment};
-
-    let anno = anno_scale as f64;
-
-    // Map Attribute alignment enums to the same h/v anchor fractions used by
-    // Text. Kept local because the Attribute enum is distinct from Text's.
-    let attr_h_anchor = |ha: AttrHA| -> f64 {
-        match ha {
-            AttrHA::Left => 0.0,
-            AttrHA::Center | AttrHA::Middle | AttrHA::Aligned | AttrHA::Fit => 0.5,
-            AttrHA::Right => 1.0,
-        }
-    };
-    let attr_v_anchor = |va: AttrVA| -> f64 {
-        match va {
-            AttrVA::Baseline | AttrVA::Bottom => 0.0,
-            AttrVA::Middle => 0.5,
-            AttrVA::Top => 1.0,
-        }
-    };
-    let attr_use_align_pt = |ha: AttrHA, va: AttrVA| -> bool {
-        !matches!((ha, va), (AttrHA::Left, AttrVA::Baseline))
-    };
-
-    let (ix, iy, iz, w, h, rot, h_anchor, v_anchor) = match e {
-        EntityType::Text(t) => {
-            let h_world = t.height * anno;
-            let w_factor = if t.width_factor > 0.0 { t.width_factor } else { 1.0 };
-            let n = t.value.chars().count().max(1) as f64;
-            // Approximate glyph width: AutoCAD's stroke fonts average ~0.6 em.
-            let w_world = n * h_world * w_factor * 0.6;
-            let h_anchor = match t.horizontal_alignment {
-                TextHorizontalAlignment::Left => 0.0,
-                TextHorizontalAlignment::Center
-                | TextHorizontalAlignment::Middle
-                | TextHorizontalAlignment::Aligned
-                | TextHorizontalAlignment::Fit => 0.5,
-                TextHorizontalAlignment::Right => 1.0,
-            };
-            let v_anchor = match t.vertical_alignment {
-                TextVerticalAlignment::Baseline | TextVerticalAlignment::Bottom => 0.0,
-                TextVerticalAlignment::Middle => 0.5,
-                TextVerticalAlignment::Top => 1.0,
-            };
-            // AutoCAD writes `alignment_point` (DXF 11) whenever the text
-            // isn't simple Left+Baseline; in that case it — not the
-            // insertion_point — is the anchor the alignment fractions map to.
-            let use_alignment_pt = !matches!(
-                (t.horizontal_alignment, t.vertical_alignment),
-                (
-                    TextHorizontalAlignment::Left,
-                    TextVerticalAlignment::Baseline,
-                )
-            );
-            let anchor = match (use_alignment_pt, t.alignment_point) {
-                (true, Some(p)) => p,
-                _ => t.insertion_point,
-            };
-            (
-                anchor.x,
-                anchor.y,
-                anchor.z,
-                w_world,
-                h_world,
-                t.rotation,
-                h_anchor,
-                v_anchor,
-            )
-        }
-        EntityType::AttributeDefinition(a) => {
-            let h_world = a.height * anno;
-            let w_factor = if a.width_factor > 0.0 { a.width_factor } else { 1.0 };
-            // Render the tag in preview when no default; matches `attribute.rs`.
-            let display = if a.default_value.is_empty() { &a.tag } else { &a.default_value };
-            let n = display.chars().count().max(1) as f64;
-            let w_world = n * h_world * w_factor * 0.6;
-            let h_anchor = attr_h_anchor(a.horizontal_alignment);
-            let v_anchor = attr_v_anchor(a.vertical_alignment);
-            let anchor = if attr_use_align_pt(a.horizontal_alignment, a.vertical_alignment) {
-                a.alignment_point
-            } else {
-                a.insertion_point
-            };
-            (
-                anchor.x, anchor.y, anchor.z, w_world, h_world, a.rotation, h_anchor, v_anchor,
-            )
-        }
-        EntityType::AttributeEntity(a) => {
-            let h_world = a.height * anno;
-            let w_factor = if a.width_factor > 0.0 { a.width_factor } else { 1.0 };
-            let n = a.value.chars().count().max(1) as f64;
-            let w_world = n * h_world * w_factor * 0.6;
-            let h_anchor = attr_h_anchor(a.horizontal_alignment);
-            let v_anchor = attr_v_anchor(a.vertical_alignment);
-            let anchor = if attr_use_align_pt(a.horizontal_alignment, a.vertical_alignment) {
-                a.alignment_point
-            } else {
-                a.insertion_point
-            };
-            (
-                anchor.x, anchor.y, anchor.z, w_world, h_world, a.rotation, h_anchor, v_anchor,
-            )
-        }
-        EntityType::Tolerance(t) => {
-            // Approximate: a feature control frame is roughly 1 line tall;
-            // width comes from char-count of the (already-stripped) text.
-            // GD&T symbols all advance one cell, so plain char count is close.
-            let raw_h = if t.text_height > 0.0 { t.text_height } else { 2.5 };
-            let h_world = raw_h * anno;
-            // Each cell ≈ 1.4 × height (matches `tolerance.rs` min_cell_w).
-            let n = t.text.chars().filter(|c| *c != '\n').count().max(1) as f64;
-            let w_world = h_world * 1.4 * n * 0.5; // rough — fine for LOD greek
-            // direction encodes rotation as a vector.
-            let rot = (t.direction.y).atan2(t.direction.x);
-            (
-                t.insertion_point.x,
-                t.insertion_point.y,
-                t.insertion_point.z,
-                w_world,
-                h_world * 1.5, // frame is taller than glyph cap by ~0.5 h
-                rot,
-                0.0, // anchored at insertion point (bottom-left)
-                0.0,
-            )
-        }
-        EntityType::MText(m) => {
-            let h_world = m.height * anno;
-            let raw_lines = (m.value.matches('\n').count() + 1) as f64;
-            let effective_lines = match mtext_lines_override {
-                Some(n) => n.max(1) as f64,
-                None => raw_lines,
-            };
-            let w_world = if m.rectangle_width > 0.0 {
-                m.rectangle_width
-            } else {
-                h_world * 8.0 * effective_lines.max(1.0)
-            };
-            // Wrap-aware override beats `rectangle_height` — the stored
-            // height can be stale on DWGs that were re-saved without
-            // updating the bounds.
-            let total_h = if mtext_lines_override.is_some() {
-                h_world * effective_lines.max(1.0) * m.line_spacing_factor.max(0.5)
-            } else {
-                m.rectangle_height.unwrap_or(
-                    h_world * raw_lines.max(1.0) * m.line_spacing_factor.max(0.5),
-                )
-            };
-            // MText `attachment_point` puts `insertion_point` at one of the
-            // 9 corners/midpoints of the text bbox. h_anchor / v_anchor are
-            // fractions from (left, bottom) of the bbox.
-            let (h_anchor, v_anchor) = match m.attachment_point {
-                AttachmentPoint::TopLeft => (0.0, 1.0),
-                AttachmentPoint::TopCenter => (0.5, 1.0),
-                AttachmentPoint::TopRight => (1.0, 1.0),
-                AttachmentPoint::MiddleLeft => (0.0, 0.5),
-                AttachmentPoint::MiddleCenter => (0.5, 0.5),
-                AttachmentPoint::MiddleRight => (1.0, 0.5),
-                AttachmentPoint::BottomLeft => (0.0, 0.0),
-                AttachmentPoint::BottomCenter => (0.5, 0.0),
-                AttachmentPoint::BottomRight => (1.0, 0.0),
-            };
-            (
-                m.insertion_point.x,
-                m.insertion_point.y,
-                m.insertion_point.z,
-                w_world,
-                total_h,
-                m.rotation,
-                h_anchor,
-                v_anchor,
-            )
-        }
-        _ => return None,
-    };
-
-    let x0 = -h_anchor * w;
-    let x1 = (1.0 - h_anchor) * w;
-    let y0 = -v_anchor * h;
-    let y1 = (1.0 - v_anchor) * h;
-
-    let (s, c) = (rot.sin(), rot.cos());
-    let rot_pt = |lx: f64, ly: f64| -> [f64; 3] {
-        let rx = lx * c - ly * s;
-        let ry = lx * s + ly * c;
-        [ix + rx, iy + ry, iz]
-    };
-
-    Some([
-        rot_pt(x0, y0),
-        rot_pt(x1, y0),
-        rot_pt(x1, y1),
-        rot_pt(x0, y1),
-    ])
-}
 
 /// Build a "low-LOD stub" wire for an entity that would otherwise be culled
 /// to nothing — the entity's AABB diagonal as a 2-point segment, plus the
@@ -5560,213 +5358,7 @@ fn lod_stub_wire(
 /// INSERT only stamps the geometry once, attribute text sits at the world
 /// position recorded on each ATTRIB. See #20.
 #[allow(clippy::too_many_arguments)]
-fn append_insert_attribute_wires(
+pub(crate) fn entity_aabb(e: &acadrust::EntityType, world_offset: [f64; 3]) -> [f32; 4] {
-    wires: &mut Vec<WireModel>,
-    document: &acadrust::CadDocument,
-    ins: &acadrust::entities::Insert,
-    insert_handle: Handle,
-    sel: bool,
-    ins_color: [f32; 4],
-    ins_pat_len: f32,
-    ins_pat: [f32; 8],
-    ins_lw_px: f32,
-    bg_color: [f32; 4],
-    is_xref: bool,
-    pslt_factor: f32,
-    anno_scale: f32,
-    world_offset: [f64; 3],
-) {
-    if ins.attributes.is_empty() {
-        return;
-    }
-    // ATTMODE (header.attribute_visibility):
-    //   0 = Off    — every attribute hidden
-    //   1 = Normal — honour per-attribute `invisible` flag (default)
-    //   2 = On     — every attribute forced visible, ignoring its flag
-    let attmode = document.header.attribute_visibility;
-    if attmode == 0 {
-        return;
-    }
-    for attr in &ins.attributes {
-        let per_attr_hidden = attr.common.invisible || attr.flags.invisible;
-        if attmode == 1 && per_attr_hidden {
-            continue;
-        }
-        let attr_entity = EntityType::AttributeEntity(attr.clone());
-        let (sub_color, sub_plen, sub_pat, sub_lw_px, sub_aci) =
-            render::render_style_for_block_sub(
-                document,
-                &attr_entity,
-                ins_color,
-                ins_pat_len,
-                ins_pat,
-                ins_lw_px,
-            );
-        let sub_color = render::adapt_to_bg(sub_color, bg_color);
-        let sub_color = if is_xref && !sel {
-            block_cache::fade_toward_bg(sub_color, bg_color)
-        } else {
-            sub_color
-        };
-        let sub_aabb = entity_aabb(&attr_entity, world_offset);
-        let mut attr_wires = tessellate::tessellate(
-            document,
-            insert_handle,
-            &attr_entity,
-            sel,
-            sub_color,
-            sub_plen * pslt_factor,
-            sub_pat.map(|v| v * pslt_factor),
-            sub_lw_px,
-            world_offset,
-            anno_scale,
-        );
-        // Use the INSERT's handle so selection / picking groups attribute
-        // text with the parent insert instead of treating it as a stray text.
-        for w in &mut attr_wires {
-            w.name = insert_handle.value().to_string();
-            w.aci = sub_aci;
-            w.aabb = sub_aabb;
-        }
-        wires.extend(attr_wires);
-    }
-}
-
-/// NaN-separated baseline segments — one per visible wrap line — for a
-/// sub-pixel Text / MText, in world-offset-subtracted f32 space. `n_lines`
-/// must be the actual rendered line count (1 for Text, the wrap-expanded
-/// count for MText). Lines are emitted top → bottom along the OBB's up
-/// direction, each at the bottom edge of its slab.
-fn text_baseline_points(
-    e: &EntityType,
-    anno_scale: f32,
-    world_offset: [f64; 3],
-    n_lines: usize,
-) -> Vec<[f32; 3]> {
-    let Some(corners) = text_obb_corners_native(e, anno_scale, Some(n_lines)) else {
-        return vec![];
-    };
-    let line_h = match e {
-        EntityType::Text(t) => (t.height * anno_scale as f64) as f32,
-        EntityType::MText(m) => (m.height * anno_scale as f64) as f32,
-        EntityType::AttributeDefinition(a) => (a.height * anno_scale as f64) as f32,
-        EntityType::AttributeEntity(a) => (a.height * anno_scale as f64) as f32,
-        EntityType::Tolerance(t) => {
-            let raw = if t.text_height > 0.0 { t.text_height } else { 2.5 };
-            (raw * anno_scale as f64) as f32
-        }
-        _ => return vec![],
-    };
-    if line_h <= 0.0 {
-        return vec![];
-    }
-    let n_lines = n_lines.max(1);
-    let [ox, oy, oz] = world_offset;
-    let cast = |p: [f64; 3]| -> [f32; 3] {
-        [(p[0] - ox) as f32, (p[1] - oy) as f32, (p[2] - oz) as f32]
-    };
-    let bl = cast(corners[0]);
-    let br = cast(corners[1]);
-    let full_tl = cast(corners[3]);
-
-    let (ux, uy, uz) = (full_tl[0] - bl[0], full_tl[1] - bl[1], full_tl[2] - bl[2]);
-    let ulen = (ux * ux + uy * uy + uz * uz).sqrt();
-    if ulen < 1e-9 {
-        return vec![bl, br];
-    }
-    let (nx, ny, nz) = (ux / ulen, uy / ulen, uz / ulen);
-
-    let mut pts = Vec::with_capacity(n_lines * 3);
-    for i in 0..n_lines {
-        // i = 0 is the topmost line — its bottom sits one line_h below
-        // the OBB top (≈ `ulen`). For n_lines > ulen/line_h the deepest
-        // baselines clamp to the OBB bottom.
-        let bot_off = ((i + 1) as f32) * line_h;
-        let along = (ulen - bot_off).max(0.0);
-        let p0 = [bl[0] + nx * along, bl[1] + ny * along, bl[2] + nz * along];
-        let p1 = [br[0] + nx * along, br[1] + ny * along, br[2] + nz * along];
-        if !pts.is_empty() {
-            pts.push([f32::NAN; 3]);
-        }
-        pts.extend_from_slice(&[p0, p1]);
-    }
-    pts
-}
-
-/// Filled tris for a greeked top-level Text / MText. One 2-triangle rect
-/// per visible line — `n_lines` is the actual rendered line count from
-/// `mtext_line_count` (1 for Text). Stacked top → bottom along the OBB's
-/// up direction. The face3d pipeline skips its 0.45 dim for wires with
-/// empty `points`, so these tris render at the literal text color.
-fn text_greek_obb_tris(
-    e: &EntityType,
-    anno_scale: f32,
-    world_offset: [f64; 3],
-    n_lines: usize,
-) -> Vec<[f32; 3]> {
-    let Some(corners) = text_obb_corners_native(e, anno_scale, Some(n_lines)) else {
-        return vec![];
-    };
-    let line_h = match e {
-        EntityType::Text(t) => (t.height * anno_scale as f64) as f32,
-        EntityType::MText(m) => (m.height * anno_scale as f64) as f32,
-        EntityType::AttributeDefinition(a) => (a.height * anno_scale as f64) as f32,
-        EntityType::AttributeEntity(a) => (a.height * anno_scale as f64) as f32,
-        EntityType::Tolerance(t) => {
-            let raw = if t.text_height > 0.0 { t.text_height } else { 2.5 };
-            (raw * anno_scale as f64) as f32
-        }
-        _ => return vec![],
-    };
-    if line_h <= 0.0 {
-        return vec![];
-    }
-    let n_lines = n_lines.max(1);
-    let [ox, oy, oz] = world_offset;
-    let cast = |p: [f64; 3]| -> [f32; 3] {
-        [(p[0] - ox) as f32, (p[1] - oy) as f32, (p[2] - oz) as f32]
-    };
-    let bl = cast(corners[0]);
-    let br = cast(corners[1]);
-    let full_tl = cast(corners[3]);
-
-    let (ux, uy, uz) = (full_tl[0] - bl[0], full_tl[1] - bl[1], full_tl[2] - bl[2]);
-    let ulen = (ux * ux + uy * uy + uz * uz).sqrt();
-    if ulen < 1e-9 {
-        return vec![];
-    }
-    let (nx, ny, nz) = (ux / ulen, uy / ulen, uz / ulen);
-
-    let mut tris = Vec::with_capacity(n_lines * 6);
-    for i in 0..n_lines {
-        let top_along = (ulen - (i as f32) * line_h).max(0.0);
-        let bot_along = (ulen - ((i + 1) as f32) * line_h).max(0.0);
-        let tl = [
-            bl[0] + nx * top_along,
-            bl[1] + ny * top_along,
-            bl[2] + nz * top_along,
-        ];
-        let tr = [
-            br[0] + nx * top_along,
-            br[1] + ny * top_along,
-            br[2] + nz * top_along,
-        ];
-        let lbl = [
-            bl[0] + nx * bot_along,
-            bl[1] + ny * bot_along,
-            bl[2] + nz * bot_along,
-        ];
-        let lbr = [
-            br[0] + nx * bot_along,
-            br[1] + ny * bot_along,
-            br[2] + nz * bot_along,
-        ];
-        tris.extend_from_slice(&[lbl, lbr, tr, lbl, tr, tl]);
-    }
-    tris
-}
-
-fn entity_aabb(e: &acadrust::EntityType, world_offset: [f64; 3]) -> [f32; 4] {
     let bbox = e.as_entity().bounding_box();
     let [ox, oy, _] = world_offset;
     let min_x = (bbox.min.x - ox) as f32;
@@ -5810,156 +5402,3 @@ fn is_unindexable_entity(e: &acadrust::EntityType) -> bool {
     )
 }
 
-/// Generate solid-fill boundary polygons for each wide segment of an LWPolyline.
-/// Returns one polygon per segment that has non-zero width; empty if the polyline
-/// has zero `constant_width` and all vertex widths are zero.
-fn wide_lwpolyline_fills(pl: &acadrust::entities::LwPolyline) -> Vec<Vec<[f32; 2]>> {
-    let hw_const = (pl.constant_width / 2.0) as f32;
-    let verts = &pl.vertices;
-    let n = verts.len();
-    if n < 2 {
-        return vec![];
-    }
-    let seg_count = if pl.is_closed { n } else { n - 1 };
-    let mut out = Vec::new();
-    for i in 0..seg_count {
-        let v0 = &verts[i];
-        let v1 = &verts[(i + 1) % n];
-        let hw0 = if v0.start_width > 1e-9 {
-            v0.start_width as f32 / 2.0
-        } else {
-            hw_const
-        };
-        let hw1 = if v0.end_width > 1e-9 {
-            v0.end_width as f32 / 2.0
-        } else {
-            hw_const
-        };
-        if hw0 < 1e-6 && hw1 < 1e-6 {
-            continue;
-        }
-        let p0 = [v0.location.x as f32, v0.location.y as f32];
-        let p1 = [v1.location.x as f32, v1.location.y as f32];
-        if let Some(poly) = polyline_segment_fill(p0, p1, hw0, hw1, v0.bulge as f32) {
-            out.push(poly);
-        }
-    }
-    out
-}
-
-/// Generate solid-fill boundary polygons for each wide segment of a Polyline2D.
-fn wide_polyline2d_fills(pl: &acadrust::entities::Polyline2D) -> Vec<Vec<[f32; 2]>> {
-    let hw_default = (pl.start_width.max(pl.end_width) / 2.0) as f32;
-    let verts = &pl.vertices;
-    let n = verts.len();
-    if n < 2 {
-        return vec![];
-    }
-    let seg_count = if pl.is_closed() { n } else { n - 1 };
-    let mut out = Vec::new();
-    for i in 0..seg_count {
-        let v0 = &verts[i];
-        let v1 = &verts[(i + 1) % n];
-        let hw0 = if v0.start_width > 1e-9 {
-            v0.start_width as f32 / 2.0
-        } else {
-            hw_default
-        };
-        let hw1 = if v0.end_width > 1e-9 {
-            v0.end_width as f32 / 2.0
-        } else {
-            hw_default
-        };
-        if hw0 < 1e-6 && hw1 < 1e-6 {
-            continue;
-        }
-        let p0 = [v0.location.x as f32, v0.location.y as f32];
-        let p1 = [v1.location.x as f32, v1.location.y as f32];
-        if let Some(poly) = polyline_segment_fill(p0, p1, hw0, hw1, v0.bulge as f32) {
-            out.push(poly);
-        }
-    }
-    out
-}
-
-/// Compute the filled boundary polygon for one polyline segment.
-/// For straight segments: a rectangle/trapezoid.
-/// For arc segments: an arc band (outer arc + reversed inner arc).
-/// Returns `None` if the segment is degenerate.
-fn polyline_segment_fill(
-    p0: [f32; 2],
-    p1: [f32; 2],
-    hw0: f32,
-    hw1: f32,
-    bulge: f32,
-) -> Option<Vec<[f32; 2]>> {
-    if bulge.abs() < 1e-9 {
-        // Straight segment — rectangle or trapezoid
-        let dx = p1[0] - p0[0];
-        let dy = p1[1] - p0[1];
-        let len = (dx * dx + dy * dy).sqrt();
-        if len < 1e-9 {
-            return None;
-        }
-        let nx = -dy / len;
-        let ny = dx / len;
-        Some(vec![
-            [p0[0] + hw0 * nx, p0[1] + hw0 * ny],
-            [p1[0] + hw1 * nx, p1[1] + hw1 * ny],
-            [p1[0] - hw1 * nx, p1[1] - hw1 * ny],
-            [p0[0] - hw0 * nx, p0[1] - hw0 * ny],
-        ])
-    } else {
-        // Arc segment — arc band polygon.
-        // Center math matches `bulge_to_arc` in modules/home/modify/explode.rs:
-        //   r = chord * (1 + b²) / (4·|b|)
-        //   d = r * (1 - b²) / (1 + b²)   (signed: negative ⇒ major arc, center
-        //                                  flips to the opposite side of chord)
-        //   center = midpoint + sign(b) · d · left_perp(chord)
-        let b = bulge as f64;
-        let b2 = b * b;
-        let dx = (p1[0] - p0[0]) as f64;
-        let dy = (p1[1] - p0[1]) as f64;
-        let chord_len = (dx * dx + dy * dy).sqrt();
-        if chord_len < 1e-9 || b.abs() < 1e-12 {
-            return None;
-        }
-        let r = chord_len * (1.0 + b2) / (4.0 * b.abs());
-        let d_perp = r * (1.0 - b2) / (1.0 + b2);
-        let mx = ((p0[0] + p1[0]) * 0.5) as f64;
-        let my = ((p0[1] + p1[1]) * 0.5) as f64;
-        let perp_x = -dy / chord_len;
-        let perp_y = dx / chord_len;
-        let sign = b.signum();
-        let cx = (mx + sign * d_perp * perp_x) as f32;
-        let cy = (my + sign * d_perp * perp_y) as f32;
-        let a0 = ((p0[1] - cy) as f32).atan2((p0[0] - cx) as f32);
-        let a1 = ((p1[1] - cy) as f32).atan2((p1[0] - cx) as f32);
-        let (sa, mut ea) = if bulge > 0.0 { (a0, a1) } else { (a1, a0) };
-        if ea < sa {
-            ea += std::f32::consts::TAU;
-        }
-        let span = ea - sa;
-        let segs = ((span.abs() / std::f32::consts::TAU) * 24.0)
-            .ceil()
-            .max(4.0) as u32;
-        let r = r as f32;
-        let r_outer = |t: f32| r + (hw0 + (hw1 - hw0) * t);
-        let r_inner = |t: f32| (r - (hw0 + (hw1 - hw0) * t)).max(0.0);
-        let mut boundary = Vec::with_capacity((segs as usize + 1) * 2);
-        let inv = 1.0 / segs as f32;
-        for j in 0..=segs {
-            let t = j as f32 * inv;
-            let ang = sa + span * t;
-            let ro = r_outer(t);
-            boundary.push([cx + ro * ang.cos(), cy + ro * ang.sin()]);
-        }
-        for j in (0..=segs).rev() {
-            let t = j as f32 * inv;
-            let ang = sa + span * t;
-            let ri = r_inner(t);
-            boundary.push([cx + ri * ang.cos(), cy + ri * ang.sin()]);
-        }
-        Some(boundary)
-    }
-}

src/scene/render.rs

@@ -279,7 +279,7 @@ pub(super) fn render_style_for(
 /// Like `render_style_for` but resolves ByBlock properties by inheriting from
 /// the INSERT entity's already-resolved style. Call this for exploded block
 /// sub-entities so that ByBlock color/linetype/lineweight propagate correctly.
-pub(super) fn render_style_for_block_sub(
+pub(crate) fn render_style_for_block_sub(
     document: &CadDocument,
     e: &EntityType,
     insert_color: [f32; 4],
@@ -314,7 +314,7 @@ pub(super) fn render_style_for_block_sub(
 /// Adapt white→black or black→white based on background luminance.
 /// White entities on light backgrounds become black, black entities on dark
 /// backgrounds become white. All other colors pass through unchanged.
-pub(super) fn adapt_to_bg(color: [f32; 4], bg: [f32; 4]) -> [f32; 4] {
+pub(crate) fn adapt_to_bg(color: [f32; 4], bg: [f32; 4]) -> [f32; 4] {
     let lum = 0.299 * bg[0] + 0.587 * bg[1] + 0.114 * bg[2];
     let is_white = color[0] > 0.95 && color[1] > 0.95 && color[2] > 0.95;
     let is_black = color[0] < 0.05 && color[1] < 0.05 && color[2] < 0.05;