From 6d515f3ae9d776042afb89c877168fa73b41a3d2 Mon Sep 17 00:00:00 2001
From: Schmarni <marnistromer@gmail.com>
Date: Fri, 17 Jan 2025 05:45:01 +0100
Subject: [PATCH] only add systems that depend on pbr when the PbrPlugin is
 added

Signed-off-by: Schmarni <marnistromer@gmail.com>
---
 crates/bevy_openxr/examples/actions.rs |  2 +-
 crates/bevy_xr/src/camera.rs           | 13 ++++---------
 2 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/crates/bevy_openxr/examples/actions.rs b/crates/bevy_openxr/examples/actions.rs
index eb7c6d9..81070f8 100644
--- a/crates/bevy_openxr/examples/actions.rs
+++ b/crates/bevy_openxr/examples/actions.rs
@@ -139,7 +139,7 @@ fn handle_flight_input(
                         let view = views.first();
                         match view {
                             Some(v) => {
-                                let reference_quat = v.pose.orientation.to_quat();
+                                let reference_quat = root_position.rotation.inverse() * v.pose.orientation.to_quat();
                                 let locomotion_vector = reference_quat.mul_vec3(input_vector);
 
                                 root_position.translation +=
diff --git a/crates/bevy_xr/src/camera.rs b/crates/bevy_xr/src/camera.rs
index b779f51..e3b0250 100644
--- a/crates/bevy_xr/src/camera.rs
+++ b/crates/bevy_xr/src/camera.rs
@@ -6,9 +6,7 @@ use bevy::ecs::component::{Component, StorageType};
 use bevy::ecs::reflect::ReflectComponent;
 use bevy::ecs::schedule::IntoSystemConfigs;
 use bevy::math::{Mat4, Vec3A};
-use bevy::pbr::{
-    build_directional_light_cascades, clear_directional_light_cascades, SimulationLightSystems,
-};
+use bevy::pbr::{PbrPlugin, PbrProjectionPlugin};
 use bevy::prelude::Projection;
 use bevy::reflect::std_traits::ReflectDefault;
 use bevy::reflect::Reflect;
@@ -30,12 +28,9 @@ impl Plugin for XrCameraPlugin {
                 .after(TransformSystem::TransformPropagate)
                 .before(VisibilitySystems::UpdateFrusta),
         );
-        app.add_systems(
-            PostUpdate,
-            build_directional_light_cascades::<XrProjection>
-                .in_set(SimulationLightSystems::UpdateDirectionalLightCascades)
-                .after(clear_directional_light_cascades),
-        );
+        if app.is_plugin_added::<PbrPlugin>() {
+            app.add_plugins(PbrProjectionPlugin::<XrProjection>::default());
+        }
         app.add_plugins((
             ExtractComponentPlugin::<XrProjection>::default(),
             ExtractComponentPlugin::<XrCamera>::default(),