enable bGravityEnabled, bSimulatePhysics, and call WakeRigidBody on grab component's owning actor at BeginPlay() if bAffectPhysicsState is enabled

Handbook/src/appendix/changelog.md

@@ -73,6 +73,7 @@ This is a minor release focusing mainly on bringing OpenXR-compatible hand track
 ### Fixed
 
 - Fixed a bug when the virtual hand inside the game is not visible but still collides with other objects inside the scene, mistakenly triggering events like OnGrabStateUpdated and OnTouchStateUpdated.
+- Fixed a bug where USGGrabComponent's `bAffectPhysicsState` does not enables physics on its owning actor at `BeginPlay()`.
 - Fixed various wrong Kismet script names and their class exports.
 - Fixed the display name for various overloads of the Blueprint-exposed function `Queue Command Vibro Level` to expose sensible display names.
 - Some Android UPL tweaks, permission, and build fixes.
@@ -95,6 +96,7 @@ This is a minor release focusing mainly on bringing OpenXR-compatible hand track
 - FSGDebugVirtualHand::Draw now accepts a FXRMotionControllerData parameter instead of all WristLocation, WristRotation, JointPositions, and JointRotations parameters.
 - FSGDebugVirtualHandSettings has been renamed to FSGVirtualHandDebuggingSettings.
 - The value for USGGrabComponent's AttachmentSocketName uproperty now defaults to the value of the plugin's GrabAttachPointSocketName instead of Name_NONE.
+- The USGGrabComponent now enables `bGravityEnabled`, `bSimulatePhysics`, and calls `WakeRigidBody` on its owning actor at `BeginPlay()` if `bAffectPhysicsState` is enabled.
 - Updated the Directory Structure section of the main README file to reflect the latest toolchain support status.
 - The `/CHANGELOG.md` file has been migrated to `/Handbook/src/overview/changelog.md`
 - The `/LICENSE.md` file has been migrated to `/Handbook/src/license/senseglove-unreal-engine-plugin.md`

Source/SenseGlove/Private/SenseGlove/Components/SGGrabComponent.cpp

@@ -135,4 +135,29 @@ USGGrabComponent::FImpl::~FImpl() = default;
 void USGGrabComponent::FImplDeleter::operator()(const FImpl* P) const
 {
     delete P;
+}
+
+void USGGrabComponent::BeginPlay()
+{
+    Super::BeginPlay();
+
+    if (bAffectPhysicsState)
+    {
+        const AActor* OwnerActor{GetOwner()};
+        if (!ensureAlwaysMsgf(IsValid(OwnerActor), TEXT("Invalid OwnerActor!")))
+        {
+            return;
+        }
+
+        UPrimitiveComponent* ActorRootComponent{Cast<UPrimitiveComponent>(OwnerActor->GetRootComponent())};
+        if (!ensureAlwaysMsgf(IsValid(ActorRootComponent),
+                              TEXT("RootComponent is not a valid UPrimativeComponent!")))
+        {
+            return;
+        }
+
+        ActorRootComponent->SetEnableGravity(true);
+        ActorRootComponent->SetSimulatePhysics(true);
+        ActorRootComponent->WakeRigidBody();
+    }
 }

Source/SenseGlove/Public/SenseGlove/Components/SGGrabComponent.h

@@ -196,4 +196,7 @@ public:
     {
         bAffectPhysicsState = bInAffectPhysicsState;
     }
+
+public:
+    virtual void BeginPlay() override;
 };