Restore the collision pipeline

1 files changed, 78 insertions, 62 deletions

diff --git a/src/pipeline/user_changes.rs b/src/pipeline/user_changes.rs
index 354ff3d..34a34a2 100644
--- a/src/pipeline/user_changes.rs
+++ b/src/pipeline/user_changes.rs
@@ -37,7 +37,7 @@ pub(crate) fn handle_user_changes_to_colliders<Colliders>(
 }
 
 pub(crate) fn handle_user_changes_to_rigid_bodies<Bodies, Colliders>(
-    islands: &mut IslandManager,
+    mut islands: Option<&mut IslandManager>,
     bodies: &mut Bodies,
     colliders: &mut Colliders,
     modified_bodies: &[RigidBodyHandle],
@@ -73,65 +73,79 @@ pub(crate) fn handle_user_changes_to_rigid_bodies<Bodies, Colliders>(
         {
             // The body's status changed. We need to make sure
             // it is on the correct active set.
-            if changes.contains(RigidBodyChanges::TYPE) {
-                match status {
-                    RigidBodyType::Dynamic => {
-                        // Remove from the active kinematic set if it was there.
-                        if islands.active_kinematic_set.get(ids.active_set_id) == Some(handle) {
-                            islands.active_kinematic_set.swap_remove(ids.active_set_id);
-                            final_action =
-                                Some((FinalAction::UpdateActiveKinematicSetId, ids.active_set_id));
+            if let Some(islands) = islands.as_deref_mut() {
+                if changes.contains(RigidBodyChanges::TYPE) {
+                    match status {
+                        RigidBodyType::Dynamic => {
+                            // Remove from the active kinematic set if it was there.
+                            if islands.active_kinematic_set.get(ids.active_set_id) == Some(handle) {
+                                islands.active_kinematic_set.swap_remove(ids.active_set_id);
+                                final_action = Some((
+                                    FinalAction::UpdateActiveKinematicSetId,
+                                    ids.active_set_id,
+                                ));
+                            }
+
+                            // Add to the active dynamic set.
+                            activation.wake_up(true);
+                            // Make sure the sleep change flag is set (even if for some
+                            // reasons the rigid-body was already awake) to make
+                            // sure the code handling sleeping change adds the body to
+                            // the active_dynamic_set.
+                            changes.set(RigidBodyChanges::SLEEP, true);
                         }
-
-                        // Add to the active dynamic set.
-                        activation.wake_up(true);
-                        // Make sure the sleep change flag is set (even if for some
-                        // reasons the rigid-body was already awake) to make
-                        // sure the code handling sleeping change adds the body to
-                        // the active_dynamic_set.
-                        changes.set(RigidBodyChanges::SLEEP, true);
-                    }
-                    RigidBodyType::Kinematic => {
-                        // Remove from the active dynamic set if it was there.
-                        if islands.active_dynamic_set.get(ids.active_set_id) == Some(&handle) {
-                            islands.active_dynamic_set.swap_remove(ids.active_set_id);
-                            final_action =
-                                Some((FinalAction::UpdateActiveDynamicSetId, ids.active_set_id));
-                        }
-
-                        // Add to the active kinematic set.
-                        if islands.active_kinematic_set.get(ids.active_set_id) != Some(&handle) {
-                            ids.active_set_id = islands.active_kinematic_set.len();
-                            islands.active_kinematic_set.push(*handle);
+                        RigidBodyType::Kinematic => {
+                            // Remove from the active dynamic set if it was there.
+                            if islands.active_dynamic_set.get(ids.active_set_id) == Some(&handle) {
+                                islands.active_dynamic_set.swap_remove(ids.active_set_id);
+                                final_action = Some((
+                                    FinalAction::UpdateActiveDynamicSetId,
+                                    ids.active_set_id,
+                                ));
+                            }
+
+                            // Add to the active kinematic set.
+                            if islands.active_kinematic_set.get(ids.active_set_id) != Some(&handle)
+                            {
+                                ids.active_set_id = islands.active_kinematic_set.len();
+                                islands.active_kinematic_set.push(*handle);
+                            }
                         }
+                        RigidBodyType::Static => {}
                     }
-                    RigidBodyType::Static => {}
                 }
-            }
-
-            // Update the positions of the colliders.
-            if changes.contains(RigidBodyChanges::POSITION)
-                || changes.contains(RigidBodyChanges::COLLIDERS)
-            {
-                rb_colliders.update_positions(colliders, modified_colliders, &poss.position);
 
-                if status.is_kinematic()
-                    && islands.active_kinematic_set.get(ids.active_set_id) != Some(handle)
+                // Update the positions of the colliders.
+                if changes.contains(RigidBodyChanges::POSITION)
+                    || changes.contains(RigidBodyChanges::COLLIDERS)
                 {
-                    ids.active_set_id = islands.active_kinematic_set.len();
-                    islands.active_kinematic_set.push(*handle);
+                    rb_colliders.update_positions(colliders, modified_colliders, &poss.position);
+
+                    if status.is_kinematic()
+                        && islands.active_kinematic_set.get(ids.active_set_id) != Some(handle)
+                    {
+                        ids.active_set_id = islands.active_kinematic_set.len();
+                        islands.active_kinematic_set.push(*handle);
+                    }
                 }
-            }
 
-            // Push the body to the active set if it is not
-            // sleeping and if it is not already inside of the active set.
-            if changes.contains(RigidBodyChanges::SLEEP)
-                && !activation.sleeping // May happen if the body was put to sleep manually.
-                && status.is_dynamic() // Only dynamic bodies are in the active dynamic set.
-                && islands.active_dynamic_set.get(ids.active_set_id) != Some(handle)
-            {
-                ids.active_set_id = islands.active_dynamic_set.len(); // This will handle the case where the activation_channel contains duplicates.
-                islands.active_dynamic_set.push(*handle);
+                // Push the body to the active set if it is not
+                // sleeping and if it is not already inside of the active set.
+                if changes.contains(RigidBodyChanges::SLEEP)
+                    && !activation.sleeping // May happen if the body was put to sleep manually.
+                    && status.is_dynamic() // Only dynamic bodies are in the active dynamic set.
+                    && islands.active_dynamic_set.get(ids.active_set_id) != Some(handle)
+                {
+                    ids.active_set_id = islands.active_dynamic_set.len(); // This will handle the case where the activation_channel contains duplicates.
+                    islands.active_dynamic_set.push(*handle);
+                }
+            } else {
+                // We don't use islands. So just update the colliders' positions.
+                if changes.contains(RigidBodyChanges::POSITION)
+                    || changes.contains(RigidBodyChanges::COLLIDERS)
+                {
+                    rb_colliders.update_positions(colliders, modified_colliders, &poss.position);
+                }
             }
 
             bodies.set_internal(handle.0, RigidBodyChanges::empty());
@@ -140,16 +154,18 @@ pub(crate) fn handle_user_changes_to_rigid_bodies<Bodies, Colliders>(
         }
 
         // Adjust some ids, if needed.
-        if let Some((action, id)) = final_action {
-            let active_set = match action {
-                FinalAction::UpdateActiveKinematicSetId => &mut islands.active_kinematic_set,
-                FinalAction::UpdateActiveDynamicSetId => &mut islands.active_dynamic_set,
-            };
-
-            if id < active_set.len() {
-                bodies.map_mut_internal(active_set[id].0, |ids2: &mut RigidBodyIds| {
-                    ids2.active_set_id = id;
-                });
+        if let Some(islands) = islands.as_deref_mut() {
+            if let Some((action, id)) = final_action {
+                let active_set = match action {
+                    FinalAction::UpdateActiveKinematicSetId => &mut islands.active_kinematic_set,
+                    FinalAction::UpdateActiveDynamicSetId => &mut islands.active_dynamic_set,
+                };
+
+                if id < active_set.len() {
+                    bodies.map_mut_internal(active_set[id].0, |ids2: &mut RigidBodyIds| {
+                        ids2.active_set_id = id;
+                    });
+                }
             }
         }
     }