use a shader def for MAX_DIRECTIONAL_LIGHTS to be sure to always have the correct value in shader

Author: mockersf

crates/bevy_pbr/src/render/light.rs

@@ -321,6 +321,10 @@ impl SpecializedMeshPipeline for ShadowPipeline {
 
         let mut bind_group_layout = vec![self.view_layout.clone()];
         let mut shader_defs = Vec::new();
+        shader_defs.push(ShaderDefVal::Int(
+            "MAX_DIRECTIONAL_LIGHTS".to_string(),
+            MAX_DIRECTIONAL_LIGHTS as i32,
+        ));
 
         if layout.contains(Mesh::ATTRIBUTE_JOINT_INDEX)
             && layout.contains(Mesh::ATTRIBUTE_JOINT_WEIGHT)

crates/bevy_pbr/src/render/mesh.rs

@@ -1,7 +1,7 @@
 use crate::{
     GlobalLightMeta, GpuLights, GpuPointLights, LightMeta, NotShadowCaster, NotShadowReceiver,
     ShadowPipeline, ViewClusterBindings, ViewLightsUniformOffset, ViewShadowBindings,
-    CLUSTERED_FORWARD_STORAGE_BUFFER_COUNT,
+    CLUSTERED_FORWARD_STORAGE_BUFFER_COUNT, MAX_DIRECTIONAL_LIGHTS,
 };
 use bevy_app::Plugin;
 use bevy_asset::{load_internal_asset, Assets, Handle, HandleUntyped};
@@ -579,6 +579,11 @@ impl SpecializedMeshPipeline for MeshPipeline {
             vertex_attributes.push(Mesh::ATTRIBUTE_NORMAL.at_shader_location(1));
         }
 
+        shader_defs.push(ShaderDefVal::Int(
+            "MAX_DIRECTIONAL_LIGHTS".to_string(),
+            MAX_DIRECTIONAL_LIGHTS as i32,
+        ));
+
         if layout.contains(Mesh::ATTRIBUTE_UV_0) {
             shader_defs.push(String::from("VERTEX_UVS").into());
             vertex_attributes.push(Mesh::ATTRIBUTE_UV_0.at_shader_location(2));

crates/bevy_pbr/src/render/mesh_view_types.wgsl

@@ -42,7 +42,7 @@ let DIRECTIONAL_LIGHT_FLAGS_SHADOWS_ENABLED_BIT: u32 = 1u;
 
 struct Lights {
     // NOTE: this array size must be kept in sync with the constants defined in bevy_pbr/src/render/light.rs
-    directional_lights: array<DirectionalLight, 1u>,
+    directional_lights: array<DirectionalLight, #{MAX_DIRECTIONAL_LIGHTS}u>,
     ambient_color: vec4<f32>,
     // x/y/z dimensions and n_clusters in w
     cluster_dimensions: vec4<u32>,