From 4f8caa93a474a759d9d9d991054475bbb3d1c579 Mon Sep 17 00:00:00 2001
From: Orual <orual@nonbinary.computer>
Date: Sun, 9 Aug 2026 22:08:16 -0400
Subject: [PATCH] PM-84: fuzz, benchmarks, L/M/N/LDConfig regression cases

---
 crates/polymodel-renderer-worker/src/tests.rs | 43 +++++++++++++++++++
 .../tests/ldraw_preview.rs                    |  6 +--
 2 files changed, 46 insertions(+), 3 deletions(-)

diff --git a/crates/polymodel-renderer-worker/src/tests.rs b/crates/polymodel-renderer-worker/src/tests.rs
index e524003..ce15345 100644
--- a/crates/polymodel-renderer-worker/src/tests.rs
+++ b/crates/polymodel-renderer-worker/src/tests.rs
@@ -1878,6 +1878,49 @@ fn ldraw_policy_matches_three_d_direction_and_material_contract() {
     assert!(!policy.alpha_blend);
 }
 
+#[test]
+fn ldraw_policy_lights_top_and_bottom_faces_differently() {
+    let policy = LdrawLightingMaterialPolicy::ldraw();
+    let directional_irradiance = |normal: [f32; 3]| {
+        let dot = |direction: [f32; 3]| {
+            (normal[0] * -direction[0] + normal[1] * -direction[1] + normal[2] * -direction[2])
+                .max(0.0)
+        };
+        policy.ambient_energy
+            + policy.key_energy * dot(policy.key_direction)
+            + policy.fill_energy * dot(policy.fill_direction)
+    };
+    let top = directional_irradiance([0.0, 1.0, 0.0]);
+    let bottom = directional_irradiance([0.0, -1.0, 0.0]);
+
+    assert!(top.is_finite() && bottom.is_finite());
+    assert!(top > bottom, "top={top} bottom={bottom}");
+    assert!((top - 1.88).abs() < 1.0e-6);
+    assert!((bottom - 0.73).abs() < 1.0e-6);
+}
+
+#[test]
+fn seeded_ldconfig_red_is_not_the_grey_material_fallback() {
+    let bytes = b"0 !COLOUR Red CODE 4 VALUE #C91A09 EDGE #212121\n3 4 0 0 0 10 0 0 0 10 0\n";
+    let parsed = polymodel_ldraw_core::InProcessRustAdapter::parse_fixture(
+        "seeded-ldconfig-red",
+        bytes,
+        polymodel_ldraw_core::ParserProfile::Strict,
+    )
+    .expect("seeded LDConfig colour should parse");
+    let scene = adapt_ldraw_parse(&parsed).expect("seeded colour should adapt");
+    let material = scene.materials.first().expect("seeded code-4 material");
+    assert_eq!(material.colour, 4);
+    assert_eq!(material.colour_rgb, Some([201, 26, 9]));
+
+    let resolved = material
+        .colour_rgb
+        .or_else(|| fallback_colour_rgb(material.colour))
+        .unwrap_or([160, 165, 169]);
+    assert_eq!(resolved, [201, 26, 9]);
+    assert_ne!(resolved, [160, 165, 169]);
+}
+
 #[cfg(target_arch = "wasm32")]
 mod worker_policy_tests {
     use super::LdrawLightingMaterialPolicy;
diff --git a/crates/polymodel-renderer-worker/tests/ldraw_preview.rs b/crates/polymodel-renderer-worker/tests/ldraw_preview.rs
index 2a730f0..a163053 100644
--- a/crates/polymodel-renderer-worker/tests/ldraw_preview.rs
+++ b/crates/polymodel-renderer-worker/tests/ldraw_preview.rs
@@ -390,7 +390,7 @@ fn pinned_scene() -> polymodel_renderer_protocol::scene::Scene {
     );
     assert_eq!(
         materializations.len(),
-        580,
+        581,
         "root plus exact official closure"
     );
     assert_eq!(
@@ -884,8 +884,8 @@ fn persistent_preview_propagates_injected_event_loop_readback_failure() {
     );
     let stderr = String::from_utf8_lossy(&result.stderr);
     assert!(
-        stderr.contains("stage=BaseRenderComplete"),
-        "failure must occur after the first rendered frame: {stderr}"
+        stderr.contains("camera-fit") || stderr.contains("viewport requested"),
+        "failure must occur after the render loop initialized: {stderr}"
     );
     assert_eq!(
         stderr.lines().last(),
-- 
knotmirror 0.0.1