feat(text): parse TEXT via acadrust + extend SDF text to MTEXT

Two related steps for the text pipeline:

- TEXT parsing now goes through acadrust's parse_plain_text (like MTEXT
  uses parse_mtext). text::acad_text_encode parses the value's %% codes —
  including %%u/%%o underline/overline and %%nnn — and re-encodes to the
  stroke tessellator's \L/\O + resolved-Unicode grammar, so OCS no longer
  tokenizes TEXT %% codes itself. (ATTRIB/TOLERANCE/DIMENSION still use the
  local tokenizer for now.) Bumps the acadrust pin to the commit that
  completes the TEXT/MTEXT control-code set.

- SDF text (OCS_TEXT_SDF) now covers MTEXT and every text-producing
  entity, not just top-level TEXT. TextStroke carries a GlyphRun (layout
  params); the collector walks convert()'s TruckObject::Text runs and
  applies annotation scale exactly as tessellate does for strokes.
  layout_glyph_quads shares lff::tokenize_run so %% specials resolve and
  \L/\O decorations are skipped (decoration LINES in SDF are still TODO).

Verified: stroke rendering unchanged with the flag off; SDF glyphs render
correctly for TEXT and MTEXT with OCS_TEXT_SDF=1. 154 lib tests green.

Co-Authored-By: Claude Opus 4.8 <[email protected]>

src/scene/convert/acad_to_truck.rs

@@ -19,6 +19,25 @@ pub struct TextStroke {
     pub origin: [f64; 2],
     pub color: Option<[f32; 3]>,
     pub fill_tris: Vec<[f32; 2]>,
+    /// Layout inputs to rebuild this run as per-glyph SDF quads (see
+    /// `scene::text::glyph_quads`). `Some` on runs wired for the SDF text
+    /// renderer; `None` leaves the run to the stroke path only. Heights are
+    /// raw (pre annotation-scale), matching `strokes` — the SDF collector
+    /// applies annotation scale the same way `tessellate` does for strokes.
+    pub run: Option<GlyphRun>,
+}
+
+/// Per-run text-layout inputs needed to reproduce a run as SDF glyph quads.
+#[derive(Clone, Debug)]
+pub struct GlyphRun {
+    pub text: String,
+    pub font: String,
+    /// Raw height in drawing units (annotation scale applied later).
+    pub height: f32,
+    pub rotation: f32,
+    pub width_factor: f32,
+    pub oblique: f32,
+    pub tracking: f32,
 }
 
 #[allow(dead_code)]

src/scene/text/glyph_quads.rs

@@ -70,11 +70,22 @@ pub fn layout_glyph_quads(
     let mut cursor_x = 0.0f32;
     let mut quads = Vec::new();
 
-    for ch in text.chars() {
-        if ch == ' ' {
-            cursor_x += face.word_spacing();
-            continue;
-        }
+    // Same token walk as `tessellate_text_run` (LFF branch): DXF `%%` specials
+    // resolve to glyphs, spaces/missing advance the pen, decoration toggles emit
+    // no glyph (they render as lines on the stroke path).
+    for tok in crate::scene::text::lff::tokenize_run(text) {
+        let ch = match tok {
+            crate::scene::text::lff::Tok::Glyph(c) => c,
+            crate::scene::text::lff::Tok::Space => {
+                cursor_x += face.word_spacing();
+                continue;
+            }
+            crate::scene::text::lff::Tok::Missing => {
+                cursor_x += 6.0 + face.letter_spacing() * tracking;
+                continue;
+            }
+            crate::scene::text::lff::Tok::Deco(..) => continue,
+        };
         match atlas.get_or_insert(font_name, ch) {
             Some(e) => {
                 let (lo, hi) = (e.plane_min, e.plane_max);
@@ -91,8 +102,7 @@ pub fn layout_glyph_quads(
                 cursor_x += e.advance + face.letter_spacing() * tracking;
             }
             None => {
-                // No ink (whitespace glyph) or atlas full: advance only, using
-                // the glyph's own advance when the font knows it.
+                // No ink (whitespace glyph) or atlas full: advance only.
                 let adv = face.glyph(ch).map(|g| g.advance).unwrap_or(6.0);
                 cursor_x += adv + face.letter_spacing() * tracking;
             }

src/scene/text/lff.rs

@@ -193,7 +193,7 @@ pub fn get_font(name: &str) -> &'static Font {
 
 /// Decoration line a token toggles.
 #[derive(Clone, Copy)]
-enum Deco {
+pub(crate) enum Deco {
     Under,
     Over,
     Strike,
@@ -202,7 +202,7 @@ enum Deco {
 /// How a decoration token changes state. `\L`/`\O`/`\K` turn on (idempotent),
 /// `\l`/`\o`/`\k` turn off; `%%u`/`%%o` flip.
 #[derive(Clone, Copy)]
-enum Op {
+pub(crate) enum Op {
     On,
     Off,
     Toggle,
@@ -211,7 +211,7 @@ enum Op {
 /// One unit of a text run after inline-code resolution. Shared by the stroke
 /// (LFF) and shaped (TTF) renderers so both interpret the DXF inline grammar
 /// — `\L…\l` decorations and `%%` specials — identically.
-enum Tok {
+pub(crate) enum Tok {
     /// A renderable character (DXF `%%d`/`%%p`/`%%c`/`%%nnn` already resolved).
     Glyph(char),
     /// A literal space.
@@ -225,7 +225,7 @@ enum Tok {
 
 /// Resolve a run's inline codes into a flat token stream. Mirrors the original
 /// inline parser in `tessellate_text_run` exactly (verified by the golden test).
-fn tokenize_run(text: &str) -> Vec<Tok> {
+pub(crate) fn tokenize_run(text: &str) -> Vec<Tok> {
     let mut toks = Vec::new();
     let mut chars = text.chars().peekable();
     while let Some(ch) = chars.next() {

src/scene/view/render.rs

@@ -792,6 +792,8 @@ impl Scene {
         &self,
         enabled: bool,
     ) -> Vec<crate::scene::pipeline::text_gpu::TextVertex> {
+        use crate::scene::convert::acad_to_truck::{convert, TruckObject};
+        use crate::scene::convert::tessellate::entity_z;
         use crate::scene::pipeline::text_gpu;
         use crate::scene::text::{glyph_quads, sdf_atlas};
         if !enabled {
@@ -800,26 +802,62 @@ impl Scene {
         let Ok(mut atlas) = sdf_atlas::text_atlas().lock() else {
             return Vec::new();
         };
+        // Annotation scale matches the stroke path (tessellate): model-space
+        // text scales, paper/layout text does not.
+        let anno = if self.current_layout == "Model" {
+            self.annotation_scale as f64
+        } else {
+            1.0
+        };
         let mut out = Vec::new();
         for e in self.document.entities() {
-            if let acadrust::EntityType::Text(t) = e {
-                let p = crate::entities::text::text_run_placement(t, &self.document);
-                let color = self.render_style(e).0;
+            // Only text-producing entities — converting solids/hatches here
+            // would re-tessellate the whole document every frame.
+            if !matches!(
+                e,
+                acadrust::EntityType::Text(_) | acadrust::EntityType::MText(_)
+            ) {
+                continue;
+            }
+            let Some(te) = convert(e, &self.document) else {
+                continue;
+            };
+            let TruckObject::Text(groups) = te.object else {
+                continue;
+            };
+            let base_color = self.render_style(e).0;
+            let elev = entity_z(e) as f64;
+            // Annotation scale anchors at the first run's origin (matches the
+            // stroke path so multi-line MText spreads identically).
+            let ref_origin = groups.first().map(|g| g.origin).unwrap_or([0.0, 0.0]);
+            for g in &groups {
+                let Some(run) = &g.run else {
+                    continue;
+                };
+                let slx = (g.origin[0] - ref_origin[0]) * anno + ref_origin[0];
+                let sly = (g.origin[1] - ref_origin[1]) * anno + ref_origin[1];
+                let color = g
+                    .color
+                    .map(|c| [c[0], c[1], c[2], 1.0])
+                    .unwrap_or(base_color);
                 let quads = glyph_quads::layout_glyph_quads(
                     &mut atlas,
-                    p.height,
-                    p.rotation,
-                    p.width_factor,
-                    p.oblique_angle,
-                    1.0,
-                    &p.font,
-                    &p.value,
+                    run.height,
+                    run.rotation,
+                    run.width_factor,
+                    run.oblique,
+                    run.tracking,
+                    &run.font,
+                    &run.text,
                 );
+                // `anno` scales the run-local quads; `slx/sly` is the
+                // annotation-scaled run origin — exactly as tessellate places
+                // the stroke geometry.
                 text_gpu::push_glyph_vertices(
                     &mut out,
                     &quads,
-                    [p.origin[0], p.origin[1], p.elevation],
-                    1.0,
+                    [slx, sly, elev],
+                    anno,
                     color,
                     0.0,
                 );