feat(terrain): separate shade material selections

4 files changed, 65 insertions, 5 deletions

diff --git a/apps/fparkan-cli/src/main.rs b/apps/fparkan-cli/src/main.rs
index c59ca1f..e469509 100644
--- a/apps/fparkan-cli/src/main.rs
+++ b/apps/fparkan-cli/src/main.rs
@@ -128,6 +128,12 @@ struct TerrainInspectOutput {
     faces: usize,
     slots: usize,
     material_tags: Vec<TerrainMaterialTagCount>,
+    shade_material_pairs: usize,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    shade_material_lookup_min: Option<u16>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    shade_material_lookup_max: Option<u16>,
+    shade_batch_boundaries: usize,
 }
 
 #[derive(Serialize)]
@@ -473,6 +479,22 @@ fn inspect_terrain(args: &[String]) -> Result<(), String> {
         .map(|(tag, faces)| TerrainMaterialTagCount { tag, faces })
         .collect::<Vec<_>>();
     material_tags.sort_unstable_by_key(|entry| entry.tag);
+    let shade_material_pairs = (0..terrain.slots.slots_raw.len())
+        .filter_map(|slot_index| terrain.slot_material_pairs(slot_index))
+        .flatten()
+        .collect::<Vec<_>>();
+    let shade_material_lookup_min = shade_material_pairs
+        .iter()
+        .map(|pair| pair.shade_selection().material_index)
+        .min();
+    let shade_material_lookup_max = shade_material_pairs
+        .iter()
+        .map(|pair| pair.shade_selection().material_index)
+        .max();
+    let shade_batch_boundaries = shade_material_pairs
+        .iter()
+        .filter(|pair| pair.flags & 0x0010 != 0)
+        .count();
     println!(
         "{}",
         serialize_json(&TerrainInspectOutput {
@@ -484,6 +506,10 @@ fn inspect_terrain(args: &[String]) -> Result<(), String> {
             faces: terrain.faces.len(),
             slots: terrain.slots.slots_raw.len(),
             material_tags,
+            shade_material_pairs: shade_material_pairs.len(),
+            shade_material_lookup_min,
+            shade_material_lookup_max,
+            shade_batch_boundaries,
         })?
     );
     Ok(())
@@ -733,12 +759,16 @@ mod tests {
                 TerrainMaterialTagCount { tag: 0, faces: 1 },
                 TerrainMaterialTagCount { tag: 3, faces: 1 },
             ],
+            shade_material_pairs: 2,
+            shade_material_lookup_min: Some(1),
+            shade_material_lookup_max: Some(2),
+            shade_batch_boundaries: 1,
         })
         .expect("serialize terrain inspection");
 
         assert_eq!(
             json,
-            "{\"schema_version\":\"fparkan-terrain-inspect-v1\",\"path\":\"DATA/MAPS/AutoMAP/Land.msh\",\"positions\":3,\"min\":[-1.0,-2.0,-3.0],\"max\":[4.0,5.0,6.0],\"faces\":2,\"slots\":4,\"material_tags\":[{\"tag\":0,\"faces\":1},{\"tag\":3,\"faces\":1}]}"
+            "{\"schema_version\":\"fparkan-terrain-inspect-v1\",\"path\":\"DATA/MAPS/AutoMAP/Land.msh\",\"positions\":3,\"min\":[-1.0,-2.0,-3.0],\"max\":[4.0,5.0,6.0],\"faces\":2,\"slots\":4,\"material_tags\":[{\"tag\":0,\"faces\":1},{\"tag\":3,\"faces\":1}],\"shade_material_pairs\":2,\"shade_material_lookup_min\":1,\"shade_material_lookup_max\":2,\"shade_batch_boundaries\":1}"
         );
     }
 }
diff --git a/crates/fparkan-terrain-format/src/lib.rs b/crates/fparkan-terrain-format/src/lib.rs
index ce97d62..764de09 100644
--- a/crates/fparkan-terrain-format/src/lib.rs
+++ b/crates/fparkan-terrain-format/src/lib.rs
@@ -211,6 +211,22 @@ pub struct TerrainMaterialPair {
     pub flags: u16,
 }
 
+impl TerrainMaterialPair {
+    /// Returns the material-manager selection used by `GetShade`.
+    ///
+    /// `GetShade` owns a manager loaded only with `Shade.wea`, so its
+    /// 16-bit lookup occupies row bits of that manager's table zero. It is
+    /// deliberately separate from the `Land1.wea`/`Land2.wea` selections
+    /// carried by [`TerrainMaterialLayers`].
+    #[must_use]
+    pub const fn shade_selection(self) -> TerrainMaterialSelection {
+        TerrainMaterialSelection {
+            table_index: 0,
+            material_index: self.material_lookup,
+        }
+    }
+}
+
 impl TerrainSlotTable {
     /// Returns the render-dispatch header for one decoded slot record.
     #[must_use]
@@ -1569,6 +1585,13 @@ mod tests {
                 },
             ])
         );
+        assert_eq!(
+            document.slot_material_pairs(0).expect("material pairs")[0].shade_selection(),
+            TerrainMaterialSelection {
+                table_index: 0,
+                material_index: 0x0102,
+            }
+        );
         assert_eq!(document.slot_material_pairs(1), None);
 
         document.slots.slots_raw[0][2..4].copy_from_slice(&3_u16.to_le_bytes());
diff --git a/crates/fparkan-terrain/src/lib.rs b/crates/fparkan-terrain/src/lib.rs
index 4eef871..a69df2a 100644
--- a/crates/fparkan-terrain/src/lib.rs
+++ b/crates/fparkan-terrain/src/lib.rs
@@ -27,7 +27,9 @@ use std::collections::VecDeque;
 ///
 /// Applications access this semantic terrain API through this terrain crate
 /// rather than taking a direct dependency on the binary-format parser.
-pub use fparkan_terrain_format::{TerrainMaterialLayers, TerrainMaterialSelection};
+pub use fparkan_terrain_format::{
+    TerrainMaterialLayers, TerrainMaterialPair, TerrainMaterialSelection,
+};
 
 /// Terrain world.
 #[derive(Clone, Debug, Default)]
diff --git a/docs/tomes/05-render.md b/docs/tomes/05-render.md
index 5dd2e0c..f6f7832 100644
--- a/docs/tomes/05-render.md
+++ b/docs/tomes/05-render.md
@@ -1584,9 +1584,14 @@ index, then groups the pairs by material lookup before constructing draw work.
 `TerrainSlotTable::render_dispatch` exposes exactly those two proven disk
 fields, while `LandMeshDocument::slot_material_pairs` decodes the selected
 type-11 entries as `{ material_lookup: u16, flags: u16 }`. Flag `0x0010` is a
-proven batch boundary in `GetShade`; the lookup's mapping to the two WEAR
-tables, the meanings of its remaining flags, and the final blend operation
-remain unassigned.
+proven batch boundary in `GetShade`. Crucially, this lookup does **not** select
+either map-local Land table: the `GetShade` constructor loads its own one-table
+manager from `system.rlb` resource `Shade.wea`, so the 16-bit value is that
+manager's table-zero row. `TerrainMaterialPair::shade_selection` records this
+separate selector instead of conflating it with `Land1.wea`/`Land2.wea`. The
+AutoDemo inspector now reports 128 slots, 3,174 addressed shade pairs, selector
+range `0..3173`, and 392 `0x0010` batch boundaries. The meanings of remaining
+flags and the final blend operation remain unassigned.
 
 The static Vulkan bridge now carries each contiguous face run as a separate
 draw range keyed by the original packed `material_tag`; it neither reorders