From 5b38989ac4a5b02f577407106009a514b8256fc5 Mon Sep 17 00:00:00 2001
From: atlv <rodol@rivalrebels.com>
Date: Sun, 6 Jul 2025 15:36:58 -0400
Subject: [PATCH] dont hard code clustering limits on cpu side so they can be
 informed by Limits later (#19985)

# Objective

- prepare bevy_light for split
- make limits more dynamically configurable

## Solution

- use settings struct

## Testing

- 3d_scene, lighting
---
 crates/bevy_pbr/src/cluster/assign.rs         | 26 ++++++++++++-------
 .../src/cluster/extract_and_prepare.rs        |  2 ++
 crates/bevy_pbr/src/cluster/mod.rs            |  2 ++
 3 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/crates/bevy_pbr/src/cluster/assign.rs b/crates/bevy_pbr/src/cluster/assign.rs
index 9dc9a56b52..e204644204 100644
--- a/crates/bevy_pbr/src/cluster/assign.rs
+++ b/crates/bevy_pbr/src/cluster/assign.rs
@@ -20,8 +20,7 @@ use tracing::warn;
 
 use super::{
     ClusterConfig, ClusterFarZMode, ClusteredDecal, Clusters, GlobalClusterSettings,
-    GlobalVisibleClusterableObjects, ViewClusterBindings, VisibleClusterableObjects,
-    MAX_UNIFORM_BUFFER_CLUSTERABLE_OBJECTS,
+    GlobalVisibleClusterableObjects, VisibleClusterableObjects,
 };
 use crate::{
     prelude::EnvironmentMapLight, ExtractedPointLight, LightProbe, PointLight, SpotLight,
@@ -263,7 +262,7 @@ pub(crate) fn assign_objects_to_clusters(
         }));
     }
 
-    if clusterable_objects.len() > MAX_UNIFORM_BUFFER_CLUSTERABLE_OBJECTS
+    if clusterable_objects.len() > global_cluster_settings.max_uniform_buffer_clusterable_objects
         && !global_cluster_settings.supports_storage_buffers
     {
         clusterable_objects.sort_by_cached_key(|clusterable_object| {
@@ -282,7 +281,9 @@ pub(crate) fn assign_objects_to_clusters(
         let mut clusterable_objects_in_view_count = 0;
         clusterable_objects.retain(|clusterable_object| {
             // take one extra clusterable object to check if we should emit the warning
-            if clusterable_objects_in_view_count == MAX_UNIFORM_BUFFER_CLUSTERABLE_OBJECTS + 1 {
+            if clusterable_objects_in_view_count
+                == global_cluster_settings.max_uniform_buffer_clusterable_objects + 1
+            {
                 false
             } else {
                 let clusterable_object_sphere = clusterable_object.sphere();
@@ -298,17 +299,19 @@ pub(crate) fn assign_objects_to_clusters(
             }
         });
 
-        if clusterable_objects.len() > MAX_UNIFORM_BUFFER_CLUSTERABLE_OBJECTS
+        if clusterable_objects.len()
+            > global_cluster_settings.max_uniform_buffer_clusterable_objects
             && !*max_clusterable_objects_warning_emitted
         {
             warn!(
-                "MAX_UNIFORM_BUFFER_CLUSTERABLE_OBJECTS ({}) exceeded",
-                MAX_UNIFORM_BUFFER_CLUSTERABLE_OBJECTS
+                "max_uniform_buffer_clusterable_objects ({}) exceeded",
+                global_cluster_settings.max_uniform_buffer_clusterable_objects
             );
             *max_clusterable_objects_warning_emitted = true;
         }
 
-        clusterable_objects.truncate(MAX_UNIFORM_BUFFER_CLUSTERABLE_OBJECTS);
+        clusterable_objects
+            .truncate(global_cluster_settings.max_uniform_buffer_clusterable_objects);
     }
 
     for (
@@ -448,14 +451,17 @@ pub(crate) fn assign_objects_to_clusters(
                     (xy_count.x + x_overlap) * (xy_count.y + y_overlap) * z_count as f32;
             }
 
-            if cluster_index_estimate > ViewClusterBindings::MAX_INDICES as f32 {
+            if cluster_index_estimate
+                > global_cluster_settings.view_cluster_bindings_max_indices as f32
+            {
                 // scale x and y cluster count to be able to fit all our indices
 
                 // we take the ratio of the actual indices over the index estimate.
                 // this is not guaranteed to be small enough due to overlapped tiles, but
                 // the conservative estimate is more than sufficient to cover the
                 // difference
-                let index_ratio = ViewClusterBindings::MAX_INDICES as f32 / cluster_index_estimate;
+                let index_ratio = global_cluster_settings.view_cluster_bindings_max_indices as f32
+                    / cluster_index_estimate;
                 let xy_ratio = index_ratio.sqrt();
 
                 requested_cluster_dimensions.x =
diff --git a/crates/bevy_pbr/src/cluster/extract_and_prepare.rs b/crates/bevy_pbr/src/cluster/extract_and_prepare.rs
index 56267f46b2..53187a2b02 100644
--- a/crates/bevy_pbr/src/cluster/extract_and_prepare.rs
+++ b/crates/bevy_pbr/src/cluster/extract_and_prepare.rs
@@ -47,6 +47,8 @@ pub(crate) fn make_global_cluster_settings(world: &World) -> GlobalClusterSettin
     GlobalClusterSettings {
         supports_storage_buffers,
         clustered_decals_are_usable,
+        max_uniform_buffer_clusterable_objects: MAX_UNIFORM_BUFFER_CLUSTERABLE_OBJECTS,
+        view_cluster_bindings_max_indices: ViewClusterBindings::MAX_INDICES,
     }
 }
 
diff --git a/crates/bevy_pbr/src/cluster/mod.rs b/crates/bevy_pbr/src/cluster/mod.rs
index 90af295cf6..5132326fb1 100644
--- a/crates/bevy_pbr/src/cluster/mod.rs
+++ b/crates/bevy_pbr/src/cluster/mod.rs
@@ -43,6 +43,8 @@ mod test;
 pub struct GlobalClusterSettings {
     pub supports_storage_buffers: bool,
     pub clustered_decals_are_usable: bool,
+    pub max_uniform_buffer_clusterable_objects: usize,
+    pub view_cluster_bindings_max_indices: usize,
 }
 
 /// Configure the far z-plane mode used for the furthest depth slice for clustered forward