From ff6e4a57043d7023bf13faea1b1a540032cdc468 Mon Sep 17 00:00:00 2001
From: Orual <orual@nonbinary.computer>
Date: Mon, 10 Aug 2026 09:07:19 -0400
Subject: [PATCH] PM-84: eliminate all stringified errors from renderer-worker

---
 crates/polymodel-renderer-worker/src/lib.rs | 34 ++++++++++-----------
 1 file changed, 17 insertions(+), 17 deletions(-)

diff --git a/crates/polymodel-renderer-worker/src/lib.rs b/crates/polymodel-renderer-worker/src/lib.rs
index c7cdcb4..9d90d67 100644
--- a/crates/polymodel-renderer-worker/src/lib.rs
+++ b/crates/polymodel-renderer-worker/src/lib.rs
@@ -178,12 +178,12 @@ pub enum RendererError {
     TextureDecode(String),
     #[error("parse/adaptation failure: {0}")]
     ParseAdaptation(&'static str),
-}
-
-impl From<RendererError> for String {
-    fn from(error: RendererError) -> Self {
-        error.to_string()
-    }
+    #[error("parse/adaptation failure: {0}")]
+    ParseMessage(String),
+    #[error("I/O failure: {0}")]
+    Io(String),
+    #[error("external runtime failure: {0}")]
+    External(String),
 }
 
 impl RendererError {
@@ -1453,7 +1453,7 @@ pub struct SceneVariantBinding {
 }
 
 impl SceneVariantBinding {
-    pub fn for_case(case_id: &str) -> Result<Self, String> {
+    pub fn for_case(case_id: &str) -> Result<Self, RendererError> {
         let reflected = case_id.starts_with("reflected_");
         let variant_id = if reflected { "reflected" } else { "identity" };
         Ok(Self {
@@ -1826,7 +1826,7 @@ pub fn semantic_counts(semantic: &LdMeshSemantic) -> (u64, u64) {
 fn official_texture_resources(
     closure: &polymodel_ldraw_core::ResourceClosure,
     materializations: &[Materialization],
-) -> Result<Vec<ModelResource>, String> {
+) -> Result<Vec<ModelResource>, RendererError> {
     let mut resources = Vec::new();
     for dependency in closure.texture_dependencies() {
         let Some(materialization) = materializations.iter().find(|materialization| {
@@ -1862,7 +1862,7 @@ fn official_texture_resources(
 pub fn prepare_preview_scene(
     input: &std::path::Path,
     library_root: &std::path::Path,
-) -> Result<Scene, String> {
+) -> Result<Scene, RendererError> {
     use polymodel_ldraw_core::{
         AdapterRequest, CancellationPolicy, InProcessRustAdapter, Materialization, NormalizedPath,
         ParserProfile, RootId,
@@ -1962,7 +1962,7 @@ pub fn official_materializations(
     library_root: &std::path::Path,
     root_path: &NormalizedPath,
     root_bytes: &[u8],
-) -> Result<OfficialClosure, String> {
+) -> Result<OfficialClosure, RendererError> {
     use polymodel_ldraw_core::CacheKey;
     use std::collections::{HashSet, VecDeque};
 
@@ -2333,7 +2333,7 @@ pub fn render_scene_window_configured(
     scene: &Scene,
     output: Option<&std::path::Path>,
     options: NativeRenderOptions,
-) -> Result<(), String> {
+) -> Result<(), RendererError> {
     render_scene_window_options_traced(scene, output, NativeTrace::default(), options)
 }
 
@@ -3827,7 +3827,7 @@ pub type NativeSceneModel = Vec<three_d::Gm<three_d::InstancedMesh, Rc<three_d::
 pub fn build_scene_model(
     context: &three_d::Context,
     scene: &Scene,
-) -> Result<NativeSceneModel, String> {
+) -> Result<NativeSceneModel, RendererError> {
     build_scene_model_for_view_with_resources(context, scene, None)
 }
 
@@ -3835,8 +3835,8 @@ pub fn build_scene_model_for_view_with_resources(
     context: &three_d::Context,
     scene: &Scene,
     resources: Option<&[ModelResource]>,
-) -> Result<NativeSceneModel, String> {
-    let plan = scene_render_plan(scene).map_err(|error| error.to_string())?;
+) -> Result<NativeSceneModel, RendererError> {
+    let plan = scene_render_plan(scene)?;
     build_scene_model_from_batches(
         context,
         scene,
@@ -4569,7 +4569,7 @@ pub fn build_scene_model_parts_for_style(
     scene: &Scene,
     view: [f64; 3],
     style: RenderStyle,
-) -> Result<SceneModelParts, String> {
+) -> Result<SceneModelParts, RendererError> {
     build_scene_model_parts_for_style_with_resources(context, scene, view, style, None)
 }
 
@@ -4579,9 +4579,9 @@ pub fn build_scene_model_parts_for_style_with_resources(
     view: [f64; 3],
     style: RenderStyle,
     resources: Option<&[ModelResource]>,
-) -> Result<SceneModelParts, String> {
+) -> Result<SceneModelParts, RendererError> {
     let started = Instant::now();
-    let plan = scene_render_plan(scene).map_err(|error| error.to_string())?;
+    let plan = scene_render_plan(scene)?;
     let plan_elapsed = started.elapsed();
     tracing::debug!(
         "[ldraw-preview] native-build-stage=plan elapsed_ms={} cumulative_ms={}",
-- 
knotmirror 0.0.1