add empty bind group layout

crates/bevy_render/src/lib.rs

@@ -96,6 +96,7 @@ use render_asset::{
     extract_render_asset_bytes_per_frame, reset_render_asset_bytes_per_frame,
     RenderAssetBytesPerFrame, RenderAssetBytesPerFrameLimiter,
 };
+use render_resource::init_empty_bind_group_layout;
 use renderer::{RenderAdapter, RenderDevice, RenderQueue};
 use settings::RenderResources;
 use sync_world::{
@@ -465,6 +466,8 @@ impl Plugin for RenderPlugin {
                     Render,
                     reset_render_asset_bytes_per_frame.in_set(RenderSystems::Cleanup),
                 );
+
+            render_app.add_systems(RenderStartup, init_empty_bind_group_layout);
         }
 
         app.register_type::<alpha::AlphaMode>()

crates/bevy_render/src/render_resource/bind_group_layout.rs

@@ -1,4 +1,6 @@
-use crate::define_atomic_id;
+use crate::{define_atomic_id, renderer::RenderDevice};
+use bevy_ecs::system::Res;
+use bevy_platform::sync::OnceLock;
 use bevy_utils::WgpuWrapper;
 use core::ops::Deref;
 
@@ -62,3 +64,19 @@ impl Deref for BindGroupLayout {
         &self.value
     }
 }
+
+static EMPTY_BIND_GROUP_LAYOUT: OnceLock<BindGroupLayout> = OnceLock::new();
+
+pub(crate) fn init_empty_bind_group_layout(render_device: Res<RenderDevice>) {
+    let layout = render_device.create_bind_group_layout(Some("empty_bind_group_layout"), &[]);
+    EMPTY_BIND_GROUP_LAYOUT
+        .set(layout)
+        .expect("init_empty_bind_group_layout was called more than once");
+}
+
+pub fn empty_bind_group_layout() -> BindGroupLayout {
+    EMPTY_BIND_GROUP_LAYOUT
+        .get()
+        .expect("init_empty_bind_group_layout was not called")
+        .clone()
+}