fix(render): honor terrain base-only face flags

7 files changed, 96 insertions, 23 deletions

diff --git a/adapters/fparkan-render-vulkan/shaders/triangle.frag b/adapters/fparkan-render-vulkan/shaders/triangle.frag
index 89896cf..6a6e752 100644
--- a/adapters/fparkan-render-vulkan/shaders/triangle.frag
+++ b/adapters/fparkan-render-vulkan/shaders/triangle.frag
@@ -114,7 +114,8 @@ void main() {
         0.0,
         1.0
     );
-    vec3 base_rgb = 2.0 * base.rgb * detail.rgb;
+    bool terrain_base_only = (mode & 16) != 0;
+    vec3 base_rgb = terrain_base_only ? base.rgb : 2.0 * base.rgb * detail.rgb;
     vec3 overlay_rgb = 2.0 * overlay.rgb * overlay_detail_sample.rgb;
     vec3 base_lit_rgb = base_rgb * in_base_diffuse + in_base_specular;
     vec3 overlay_lit_rgb = overlay_rgb * in_overlay_diffuse + in_overlay_specular;
diff --git a/adapters/fparkan-render-vulkan/shaders/triangle.frag.spv b/adapters/fparkan-render-vulkan/shaders/triangle.frag.spv
index 8b867bb..7b7c3da 100644
--- a/adapters/fparkan-render-vulkan/shaders/triangle.frag.spv
+++ b/adapters/fparkan-render-vulkan/shaders/triangle.frag.spv
diff --git a/adapters/fparkan-render-vulkan/src/asset_mesh.rs b/adapters/fparkan-render-vulkan/src/asset_mesh.rs
index 0de1381..3249012 100644
--- a/adapters/fparkan-render-vulkan/src/asset_mesh.rs
+++ b/adapters/fparkan-render-vulkan/src/asset_mesh.rs
@@ -865,6 +865,7 @@ fn append_node_fallback_batch(
         lightmap_index: batch.lightmap_index,
         batch_flags: batch.batch_flags,
         pipeline_state: world_pipeline_state(),
+        terrain_base_only: false,
         alpha_test_reference: VulkanStaticDrawRange::NATIVE_DEFAULT_ALPHA_TEST_REFERENCE,
     });
     Ok(())
@@ -1205,20 +1206,23 @@ fn static_terrain_draw_ranges(
     let mut ranges = Vec::new();
     let mut start_face = 0usize;
     while start_face < lod0.len() {
-        let material_index = terrain
+        let first_face = terrain
             .faces
             .get(lod0[start_face].face_index)
-            .ok_or(VulkanAssetMeshError::IndexOutOfRange)?
-            .material_tag;
+            .ok_or(VulkanAssetMeshError::IndexOutOfRange)?;
+        let material_index = first_face.material_tag;
+        let terrain_base_only = first_face.flags.0 & 0x400 == 0;
         let mut end_face = start_face + 1;
-        while end_face < lod0.len()
-            && terrain
+        while end_face < lod0.len() {
+            let next_face = terrain
                 .faces
                 .get(lod0[end_face].face_index)
-                .ok_or(VulkanAssetMeshError::IndexOutOfRange)?
-                .material_tag
-                == material_index
-        {
+                .ok_or(VulkanAssetMeshError::IndexOutOfRange)?;
+            if next_face.material_tag != material_index
+                || (next_face.flags.0 & 0x400 == 0) != terrain_base_only
+            {
+                break;
+            }
             end_face += 1;
         }
         ranges.push(VulkanStaticDrawRange {
@@ -1234,6 +1238,7 @@ fn static_terrain_draw_ranges(
             lightmap_index: u8::MAX,
             batch_flags: 0,
             pipeline_state: world_pipeline_state(),
+            terrain_base_only,
             alpha_test_reference: VulkanStaticDrawRange::NATIVE_DEFAULT_ALPHA_TEST_REFERENCE,
         });
         start_face = end_face;
@@ -1279,6 +1284,7 @@ fn static_model_indices_and_ranges(
             lightmap_index: batch.lightmap_index,
             batch_flags: batch.batch_flags,
             pipeline_state: world_pipeline_state(),
+            terrain_base_only: false,
             alpha_test_reference: VulkanStaticDrawRange::NATIVE_DEFAULT_ALPHA_TEST_REFERENCE,
         });
     }
@@ -1481,6 +1487,7 @@ mod tests {
                 lightmap_index: 0,
                 batch_flags: 0,
                 pipeline_state: world_pipeline_state(),
+                terrain_base_only: false,
                 alpha_test_reference: VulkanStaticDrawRange::NATIVE_DEFAULT_ALPHA_TEST_REFERENCE,
             }]
         );
@@ -2002,6 +2009,7 @@ mod tests {
                     lightmap_index: 0,
                     batch_flags: 0,
                     pipeline_state: world_pipeline_state(),
+                    terrain_base_only: false,
                     alpha_test_reference:
                         VulkanStaticDrawRange::NATIVE_DEFAULT_ALPHA_TEST_REFERENCE,
                 },
@@ -2012,6 +2020,7 @@ mod tests {
                     lightmap_index: 0,
                     batch_flags: 0,
                     pipeline_state: world_pipeline_state(),
+                    terrain_base_only: false,
                     alpha_test_reference:
                         VulkanStaticDrawRange::NATIVE_DEFAULT_ALPHA_TEST_REFERENCE,
                 },
@@ -2168,8 +2177,16 @@ mod tests {
     }
 
     fn terrain_face_with_tag(material_tag: u16, vertices: [u16; 3]) -> TerrainFace28 {
+        terrain_face_with_tag_and_flags(material_tag, 0, vertices)
+    }
+
+    fn terrain_face_with_tag_and_flags(
+        material_tag: u16,
+        flags: u32,
+        vertices: [u16; 3],
+    ) -> TerrainFace28 {
         TerrainFace28 {
-            flags: FullSurfaceMask(0),
+            flags: FullSurfaceMask(flags),
             material_tag,
             aux_tag: 0,
             vertices,
@@ -2201,7 +2218,7 @@ mod tests {
     }
 
     #[test]
-    fn terrain_ranges_preserve_face_order_and_packed_material_tags() {
+    fn terrain_ranges_merge_only_contiguous_equal_material_and_surface_mode() {
         let mut terrain = LandMeshDocument {
             streams: Vec::new(),
             nodes_raw: Vec::new(),
@@ -2216,27 +2233,35 @@ mod tests {
             aux14: Vec::new(),
             aux18: Vec::new(),
             faces: vec![
-                terrain_face_with_tag(0xff01, [0, 1, 2]),
-                terrain_face_with_tag(0xff01, [0, 1, 2]),
+                terrain_face_with_tag_and_flags(0xff00, 0x400, [0, 1, 2]),
+                terrain_face_with_tag_and_flags(0xff00, 0x400, [0, 1, 2]),
+                terrain_face_with_tag_and_flags(0xff00, 0, [0, 1, 2]),
                 terrain_face_with_tag(0x0102, [0, 1, 2]),
-                terrain_face_with_tag(0xff01, [0, 1, 2]),
+                terrain_face_with_tag_and_flags(0xff00, 0x400, [0, 1, 2]),
             ],
         };
-        set_terrain_lod_slots(&mut terrain, &[[0, u16::MAX]], &[[0, 4]]);
+        set_terrain_lod_slots(&mut terrain, &[[0, u16::MAX]], &[[0, 5]]);
 
         let lod0 = static_terrain_lod0_assignments(&terrain).expect("terrain LOD0");
         let ranges = static_terrain_draw_ranges(&terrain, &lod0).expect("representable terrain");
 
-        assert_eq!(ranges.len(), 3);
+        assert_eq!(ranges.len(), 4);
         assert_eq!(ranges[0].first_index, 0);
         assert_eq!(ranges[0].index_count, 6);
-        assert_eq!(ranges[0].material_index, 0xff01);
+        assert_eq!(ranges[0].material_index, 0xff00);
+        assert!(!ranges[0].terrain_base_only);
         assert_eq!(ranges[1].first_index, 6);
         assert_eq!(ranges[1].index_count, 3);
-        assert_eq!(ranges[1].material_index, 0x0102);
+        assert_eq!(ranges[1].material_index, 0xff00);
+        assert!(ranges[1].terrain_base_only);
         assert_eq!(ranges[2].first_index, 9);
         assert_eq!(ranges[2].index_count, 3);
-        assert_eq!(ranges[2].material_index, 0xff01);
+        assert_eq!(ranges[2].material_index, 0x0102);
+        assert!(ranges[2].terrain_base_only);
+        assert_eq!(ranges[3].first_index, 12);
+        assert_eq!(ranges[3].index_count, 3);
+        assert_eq!(ranges[3].material_index, 0xff00);
+        assert!(!ranges[3].terrain_base_only);
         assert!(ranges.iter().all(|range| {
             range.alpha_test_reference == VulkanStaticDrawRange::NATIVE_DEFAULT_ALPHA_TEST_REFERENCE
         }));
diff --git a/adapters/fparkan-render-vulkan/src/ffi/smoke.rs b/adapters/fparkan-render-vulkan/src/ffi/smoke.rs
index 4ad1c1b..30a42dd 100644
--- a/adapters/fparkan-render-vulkan/src/ffi/smoke.rs
+++ b/adapters/fparkan-render-vulkan/src/ffi/smoke.rs
@@ -1902,18 +1902,23 @@ impl VulkanSmokeRenderer {
                     60,
                     &material_uv_transforms,
                 );
-                let unlit = self.material_unlit.get(texture_index).ok_or(
+                let material_mode = self.material_unlit.get(texture_index).ok_or(
                     VulkanSmokeRendererError::InvariantViolation {
                         context: "static material unlit flag",
                     },
                 )?;
-                let unlit = [unlit.to_ne_bytes()];
+                let material_mode = if range.terrain_base_only {
+                    ((*material_mode).round() as i32 | 16) as f32
+                } else {
+                    *material_mode
+                };
+                let material_mode = [material_mode.to_ne_bytes()];
                 device.device().cmd_push_constants(
                     command_buffer,
                     resources.pipeline_layout,
                     vk::ShaderStageFlags::VERTEX | vk::ShaderStageFlags::FRAGMENT,
                     124,
-                    &unlit.concat(),
+                    &material_mode.concat(),
                 );
                 device.device().cmd_draw_indexed(
                     command_buffer,
@@ -2577,6 +2582,7 @@ mod tests {
                 lightmap_index: 4,
                 batch_flags: 0x108,
                 pipeline_state: base_state,
+                terrain_base_only: false,
                 alpha_test_reference: 17,
             },
             VulkanStaticDrawRange {
@@ -2586,6 +2592,7 @@ mod tests {
                 lightmap_index: u8::MAX,
                 batch_flags: 0,
                 pipeline_state: LegacyPipelineState::default(),
+                terrain_base_only: false,
                 alpha_test_reference: 0,
             },
         ];
@@ -2769,6 +2776,7 @@ mod tests {
                 lightmap_index: u8::MAX,
                 batch_flags: 0,
                 pipeline_state: fparkan_render::LegacyPipelineState::default(),
+                terrain_base_only: false,
                 alpha_test_reference: 0,
             })
             .collect::<Vec<_>>();
@@ -2792,6 +2800,7 @@ mod tests {
                 lightmap_index: u8::MAX,
                 batch_flags: 0,
                 pipeline_state: fparkan_render::LegacyPipelineState::default(),
+                terrain_base_only: false,
                 alpha_test_reference: 0,
             },
             super::super::VulkanStaticDrawRange {
@@ -2801,6 +2810,7 @@ mod tests {
                 lightmap_index: u8::MAX,
                 batch_flags: 0,
                 pipeline_state: fparkan_render::LegacyPipelineState::default(),
+                terrain_base_only: false,
                 alpha_test_reference: 0,
             },
             super::super::VulkanStaticDrawRange {
@@ -2810,6 +2820,7 @@ mod tests {
                 lightmap_index: u8::MAX,
                 batch_flags: 0,
                 pipeline_state: fparkan_render::LegacyPipelineState::default(),
+                terrain_base_only: false,
                 alpha_test_reference: 0,
             },
         ];
@@ -2833,6 +2844,7 @@ mod tests {
                 lightmap_index: u8::MAX,
                 batch_flags: 0,
                 pipeline_state: fparkan_render::LegacyPipelineState::default(),
+                terrain_base_only: false,
                 alpha_test_reference: 0,
             })
             .collect::<Vec<_>>();
@@ -2861,6 +2873,7 @@ mod tests {
                 lightmap_index: u8::MAX,
                 batch_flags: 0,
                 pipeline_state: LegacyPipelineState::default(),
+                terrain_base_only: false,
                 alpha_test_reference: 0,
             })
             .collect::<Vec<_>>();
diff --git a/adapters/fparkan-render-vulkan/src/ffi/smoke_types.rs b/adapters/fparkan-render-vulkan/src/ffi/smoke_types.rs
index ac31e9a..51f8384 100644
--- a/adapters/fparkan-render-vulkan/src/ffi/smoke_types.rs
+++ b/adapters/fparkan-render-vulkan/src/ffi/smoke_types.rs
@@ -422,6 +422,8 @@ pub struct VulkanStaticDrawRange {
     /// Bits `0x100` and `0x008` opt a range into that queue independently of
     /// the material blend category.
     pub batch_flags: u16,
+    /// Terrain ranges that use the native lit base-only path (face flag 0x400 clear).
+    pub terrain_base_only: bool,
     /// Backend-neutral fixed-function state for this source range.
     pub pipeline_state: LegacyPipelineState,
     /// Alpha-test reference in legacy 0..=255 units; dynamic material data.
@@ -754,6 +756,7 @@ impl VulkanStaticMesh {
                 material_index: 0,
                 lightmap_index: u8::MAX,
                 batch_flags: 0,
+                terrain_base_only: false,
                 pipeline_state: LegacyPipelineState::default(),
                 alpha_test_reference: 0,
             }],
@@ -989,6 +992,7 @@ mod static_mesh_tests {
                 material_index: 0,
                 lightmap_index: u8::MAX,
                 batch_flags: 0,
+                terrain_base_only: false,
                 pipeline_state: LegacyPipelineState::default(),
                 alpha_test_reference: 0,
             }],
@@ -1019,6 +1023,7 @@ mod static_mesh_tests {
                 material_index: 7,
                 lightmap_index: u8::MAX,
                 batch_flags: 0,
+                terrain_base_only: false,
                 pipeline_state: LegacyPipelineState::default(),
                 alpha_test_reference: 0,
             },
@@ -1028,6 +1033,7 @@ mod static_mesh_tests {
                 material_index: 2,
                 lightmap_index: u8::MAX,
                 batch_flags: 0,
+                terrain_base_only: false,
                 pipeline_state: LegacyPipelineState::default(),
                 alpha_test_reference: 0,
             },
diff --git a/apps/fparkan-game/src/main.rs b/apps/fparkan-game/src/main.rs
index 3b3969e..6aeaaec 100644
--- a/apps/fparkan-game/src/main.rs
+++ b/apps/fparkan-game/src/main.rs
@@ -1944,6 +1944,7 @@ fn append_environment_range(
             lightmap_index: u8::MAX,
             batch_flags: 0,
             pipeline_state,
+            terrain_base_only: false,
             alpha_test_reference: VulkanStaticDrawRange::NATIVE_DEFAULT_ALPHA_TEST_REFERENCE,
         });
     Ok(EnvironmentGpuRange {
@@ -6347,6 +6348,7 @@ mod tests {
                 LegacyBlendMode::Opaque,
                 LegacyDepthMode::TestReadOnly,
             ),
+            terrain_base_only: false,
             alpha_test_reference: 0,
         };
         let mut mesh = VulkanStaticMesh {
@@ -6405,6 +6407,7 @@ mod tests {
             lightmap_index: u8::MAX,
             batch_flags,
             pipeline_state: world_pipeline_state(blend, LegacyDepthMode::TestReadOnly),
+            terrain_base_only: false,
             alpha_test_reference: 0,
         };
 
@@ -7645,6 +7648,7 @@ mod tests {
             lightmap_index: 0,
             batch_flags,
             pipeline_state: LegacyPipelineState::default(),
+            terrain_base_only: false,
             alpha_test_reference: VulkanStaticDrawRange::NATIVE_DEFAULT_ALPHA_TEST_REFERENCE,
         };
         let mesh = VulkanStaticMesh {
diff --git a/docs/tomes/04-world.md b/docs/tomes/04-world.md
index f9c0e67..e486e18 100644
--- a/docs/tomes/04-world.md
+++ b/docs/tomes/04-world.md
@@ -430,6 +430,30 @@ full 00000040 -> compact 2000
 full 00200000 -> compact 8000
 ```
 
+Бит `0x400` в маске грани рельефа управляет detail-текстурой. В `Terrain.dll`
+метод `CShade` по смещению `+0x10` таблицы `0x10065108` ведёт к `0x10028A50`:
+он читает `flags` по смещению `+0x3C` и проверяет бит в `0x10029191`. Ветка для
+очищенного бита обнуляет указатель detail-текстуры в `0x10029427`. Затем
+`Ngi32` применяет режим 1 или 7: для RGB stage 0 умножает текстуру на diffuse-
+цвет, а stage 1 отключён. Alpha режима 1 берётся из texture, режима 7 — из
+diffuse; на проверенных непрозрачных полосах основания это различие не меняет
+цвет фрагмента. Текущий код сохраняет выбор в каждой полосе отрисовки рельефа:
+
+```rust
+let terrain_base_only = first_face.flags.0 & 0x400 == 0;
+```
+
+Фрагментный шейдер пропускает умножение на detail-текстуру:
+
+```glsl
+bool terrain_base_only = (mode & 16) != 0;
+vec3 base_rgb = terrain_base_only ? base.rgb : 2.0 * base.rgb * detail.rgb;
+```
+
+В исходных картах бит установлен у всех 275 882 граней рельефа. У полос
+основания, которые создаются процедурно при загрузке миссии, бит очищен;
+именно поэтому им нужен этот вариант без detail-текстуры.
+
 Для шестибитного material-поля используются full-биты `0x100`, `0x8000`,
 `0x10000`, `0x40000`, `0x80000` и `0x80`; они переходят соответственно в
 compact-биты `1`, `2`, `4`, `8`, `0x10`, `0x20`.