mosure · mosure · Sep 16, 2025 · Sep 16, 2025 · Sep 16, 2025 · Sep 16, 2025
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 name = "bevy_gaussian_splatting"
 description = "bevy gaussian splatting render pipeline plugin"
-version = "5.2.0"
+version = "5.2.1"
 edition = "2024"
 rust-version = "1.85.0"
 authors = ["mosure <mitchell@mosure.me>"]

diff --git a/src/render/gaussian.wgsl b/src/render/gaussian.wgsl
@@ -165,6 +165,24 @@
 #endif
 
 
+fn world_to_local_direction(ray_direction_world: vec3<f32>, transform: mat4x4<f32>) -> vec3<f32> {
+    let basis = mat3x3<f32>(
+        transform[0].xyz,
+        transform[1].xyz,
+        transform[2].xyz,
+    );
+    let basis_x = normalize(basis[0]);
+    let basis_y = normalize(basis[1]);
+    let basis_z = normalize(basis[2]);
+
+    let local = vec3<f32>(
+        dot(basis_x, ray_direction_world),
+        dot(basis_y, ray_direction_world),
+        dot(basis_z, ray_direction_world),
+    );
+
+    return normalize(local);
+}
 @vertex
 fn vs_points(
     @builtin(instance_index) instance_index: u32,
@@ -300,12 +318,13 @@ fn vs_points(
 
 // TODO: RASTERIZE_ACCELERATION
 #ifdef RASTERIZE_CLASSIFICATION
-    let ray_direction = normalize(transformed_position - view.world_position);
+    let ray_direction_world = normalize(transformed_position - view.world_position);
+    let ray_direction_local = world_to_local_direction(ray_direction_world, gaussian_uniforms.transform);
 
     #ifdef GAUSSIAN_3D_STRUCTURE
-        rgb = get_color(splat_index, ray_direction);
+        rgb = get_color(splat_index, ray_direction_local);
     #else ifdef GAUSSIAN_4D
-        rgb = get_color(splat_index, gaussian_4d.dir_t, ray_direction);
+        rgb = get_color(splat_index, gaussian_4d.dir_t, ray_direction_local);
     #endif
 
     rgb = class_to_rgb(
@@ -391,13 +410,13 @@ fn vs_points(
     rgb = base_color * scaled_mag;
 #else ifdef RASTERIZE_COLOR
     // TODO: verify color benefit for ray_direction computed at quad verticies instead of gaussian center (same as current complexity)
-    // TODO: why doesn't Transform rotation change SH color?
-    let ray_direction = normalize(transformed_position - view.world_position);
+    let ray_direction_world = normalize(transformed_position - view.world_position);
+    let ray_direction_local = world_to_local_direction(ray_direction_world, gaussian_uniforms.transform);
 
     #ifdef GAUSSIAN_3D_STRUCTURE
-        rgb = get_color(splat_index, ray_direction);
+        rgb = get_color(splat_index, ray_direction_local);
     #else ifdef GAUSSIAN_4D
-        rgb = get_color(splat_index, gaussian_4d.dir_t, ray_direction);
+        rgb = get_color(splat_index, gaussian_4d.dir_t, ray_direction_local);
     #endif
 #endif
 

diff --git a/src/sort/radix.rs b/src/sort/radix.rs
@@ -425,6 +425,7 @@ where
         settings,
     ) in gaussian_clouds.iter() {
         if settings.sort_mode != SortMode::Radix {
+            commands.entity(entity).remove::<RadixBindGroup>();
             continue;
         }
 

diff --git a/src/sort/radix.wgsl b/src/sort/radix.wgsl
@@ -195,19 +195,23 @@ fn radix_sort_c(
     workgroupBarrier();
 
     // --- Step 3: Determine deterministic global base for each digit ---
-    if (tid < #{RADIX_BASE}u) {
-        let count = local_digit_counts[tid];
-        let tile_count = max((gaussian_uniforms.count + tile_size - 1u) / tile_size, 1u);
-        let expected = sorting_pass_index * tile_count + workgroup_id.y;
+    let tile_count = max((gaussian_uniforms.count + tile_size - 1u) / tile_size, 1u);
+    let expected_ticket = sorting_pass_index * tile_count + workgroup_id.y;
 
+    // Acquire a per-tile ticket so we only serialize once per tile instead of once per digit.
+    if (tid == 0u) {
         loop {
-            let head = atomicLoad(&sorting.digit_tile_head[tid]);
-            if (head == expected) {
-                let exchange = atomicCompareExchangeWeak(&sorting.digit_tile_head[tid], expected, expected + 1u);
+            let head = atomicLoad(&sorting.assignment_counter);
+            if (head == expected_ticket) {
+                let exchange = atomicCompareExchangeWeak(&sorting.assignment_counter, expected_ticket, expected_ticket + 1u);
                 if (exchange.exchanged) { break; }
             }
         }
+    }
+    workgroupBarrier();
 
+    if (tid < #{RADIX_BASE}u) {
+        let count = local_digit_counts[tid];
         let base = atomicAdd(&sorting.digit_histogram[sorting_pass_index][tid], count);
         digit_global_base_ws[tid] = base;
     }
@@ -238,7 +242,6 @@ fn radix_sort_c(
             }
         }
     }
-
     if (sorting_pass_index == #{RADIX_DIGIT_PLACES}u - 1u && tid == 0u) {
         atomicStore(&draw_indirect.instance_count, gaussian_uniforms.count);
     }