Perf improvement

hello-world/src/test_scene.rs

@@ -5,6 +5,8 @@ use bevy::{
     render::render_resource::{AsBindGroup, ShaderRef},
 };
 
+use crate::orbit_cam::{self, OrbitCam};
+
 pub struct TestScenePlugin;
 
 impl Plugin for TestScenePlugin {
@@ -14,10 +16,17 @@ impl Plugin for TestScenePlugin {
                 prepass_enabled: true,
                 ..default()
             })
-            .add_systems(Startup, spawn_scene);
+            .add_systems(Startup, spawn_scene)
+            .add_systems(
+                Update,
+                move_plane_with_camera.after(orbit_cam::pan_orbit_camera),
+            );
     }
 }
 
+#[derive(Component)]
+struct WorldGridPlane;
+
 fn spawn_scene(
     mut cmd: Commands,
     mut meshes: ResMut<Assets<Mesh>>,
@@ -53,16 +62,28 @@ fn spawn_scene(
     cmd.spawn((
         MaterialMeshBundle {
             mesh: meshes.add(Mesh::from(shape::Plane {
-                size: 10_000.0,
+                size: 200.0,
                 subdivisions: 0,
             })),
             material: mat_proc_grid.add(ProceduralGridMaterial {}),
             ..default()
         },
         NotShadowCaster,
+        WorldGridPlane,
     ));
 }
 
+fn move_plane_with_camera(
+    mut plane: Query<(&WorldGridPlane, &mut Transform)>,
+    camera: Query<&OrbitCam>,
+) {
+    let &OrbitCam { focus, .. } = camera.single();
+    let (_, mut xform) = plane.single_mut();
+
+    xform.translation.x = focus.x;
+    xform.translation.z = focus.z;
+}
+
 #[derive(AsBindGroup, Clone, TypePath, TypeUuid)]
 #[uuid = "CE331A13-F247-4F5B-A75E-670B2BD5776A"]
 struct ProceduralGridMaterial {}