Merge remote-tracking branch 'origin/master' into 1.9

Source/Engine/Physics/Colliders/CharacterController.cpp

@@ -19,6 +19,7 @@ CharacterController::CharacterController(const SpawnParams& params)
     , _minMoveDistance(0.0f)
     , _isUpdatingTransform(false)
     , _upDirection(Vector3::Up)
+    , _gravityDisplacement(Vector3::Zero)
     , _nonWalkableMode(NonWalkableModes::PreventClimbing)
     , _lastFlags(CollisionFlags::None)
 {
@@ -148,10 +149,16 @@ CharacterController::CollisionFlags CharacterController::GetFlags() const
 CharacterController::CollisionFlags CharacterController::SimpleMove(const Vector3& speed)
 {
     const float deltaTime = Time::GetCurrentSafe()->DeltaTime.GetTotalSeconds();
-    Vector3 displacement = speed;
-    displacement += GetPhysicsScene()->GetGravity() * deltaTime;
-    displacement *= deltaTime;
-    return Move(displacement);
+    Vector3 displacement = speed + _gravityDisplacement;
+    CollisionFlags result = Move(displacement * deltaTime);
+    if ((static_cast<int>(result) & static_cast<int>(CollisionFlags::Below)) != 0)
+    {
+        // Reset accumulated gravity acceleration when we touch the ground
+        _gravityDisplacement = Vector3::Zero;
+    }
+    else
+        _gravityDisplacement += GetPhysicsScene()->GetGravity() * deltaTime;
+    return result;
 }
 
 CharacterController::CollisionFlags CharacterController::Move(const Vector3& displacement)

Source/Engine/Physics/Colliders/CharacterController.h

@@ -66,6 +66,7 @@ private:
     float _minMoveDistance;
     bool _isUpdatingTransform;
     Vector3 _upDirection;
+    Vector3 _gravityDisplacement;
     NonWalkableModes _nonWalkableMode;
     CollisionFlags _lastFlags;
 

Source/Engine/Physics/Colliders/MeshCollider.cpp

@@ -133,7 +133,13 @@ void MeshCollider::GetGeometry(CollisionShape& collision)
     // Prepare scale
     Float3 scale = _cachedScale;
     const float minSize = 0.001f;
-    scale = Float3::Max(scale.GetAbsolute(), minSize);
+    Float3 scaleAbs = scale.GetAbsolute();
+    if (scaleAbs.X < minSize)
+        scale.X = Math::Sign(scale.X) * minSize;
+    if (scaleAbs.Y < minSize)
+        scale.Y = Math::Sign(scale.Y) * minSize;
+    if (scaleAbs.Z < minSize)
+        scale.Z = Math::Sign(scale.Z) * minSize;
 
     // Setup shape (based on type)
     CollisionDataType type = CollisionDataType::None;

Source/Engine/Physics/PhysX/PhysicsBackendPhysX.cpp

@@ -321,7 +321,12 @@ class CharacterControllerHitReportPhysX : public PxUserControllerHitReport
 {
     void onHit(const PxControllerHit& hit, Collision& c)
     {
-        ASSERT_LOW_LAYER(c.ThisActor && c.OtherActor);
+        if (c.ThisActor == nullptr || c.OtherActor == nullptr)
+        {
+            // One of the actors was deleted (eg. via RigidBody destroyed by gameplay) then skip processing this collision
+            return;
+        }
+
         c.Impulse = Vector3::Zero;
         c.ThisVelocity = P2C(hit.dir) * hit.length;
         c.OtherVelocity = Vector3::Zero;
@@ -564,6 +569,7 @@ namespace
     Array<PxBase*> DeleteObjects;
 
     bool _queriesHitTriggers = true;
+    bool _enableCCD = true;
     PhysicsCombineMode _frictionCombineMode = PhysicsCombineMode::Average;
     PhysicsCombineMode _restitutionCombineMode = PhysicsCombineMode::Average;
 
@@ -697,6 +703,8 @@ PxFilterFlags FilterShader(
         pairFlags |= PxPairFlag::eNOTIFY_TOUCH_LOST;
         pairFlags |= PxPairFlag::ePOST_SOLVER_VELOCITY;
         pairFlags |= PxPairFlag::eNOTIFY_CONTACT_POINTS;
+        if (_enableCCD)
+            pairFlags |= PxPairFlag::eDETECT_CCD_CONTACT;
         return PxFilterFlag::eDEFAULT;
     }
 
@@ -1220,6 +1228,7 @@ void PhysicsBackend::Shutdown()
 void PhysicsBackend::ApplySettings(const PhysicsSettings& settings)
 {
     _queriesHitTriggers = settings.QueriesHitTriggers;
+    _enableCCD = !settings.DisableCCD;
     _frictionCombineMode = settings.FrictionCombineMode;
     _restitutionCombineMode = settings.RestitutionCombineMode;
 
@@ -1256,6 +1265,8 @@ void* PhysicsBackend::CreateScene(const PhysicsSettings& settings)
     sceneDesc.simulationEventCallback = &scenePhysX->EventsCallback;
     sceneDesc.filterShader = FilterShader;
     sceneDesc.bounceThresholdVelocity = settings.BounceThresholdVelocity;
+    if (settings.EnableEnhancedDeterminism)
+        sceneDesc.flags |= PxSceneFlag::eENABLE_ENHANCED_DETERMINISM;
     switch (settings.SolverType)
     {
     case PhysicsSolverType::ProjectedGaussSeidelIterativeSolver:

Source/Engine/Physics/PhysicsSettings.h

@@ -94,10 +94,16 @@ public:
     API_FIELD(Attributes="EditorOrder(71), EditorDisplay(\"Simulation\")")
     PhysicsBroadPhaseType BroadPhaseType = PhysicsBroadPhaseType::ParallelAutomaticBoxPruning;
 
+    /// <summary>
+    /// Enables enhanced determinism in the simulation. This has a performance impact.
+    /// </summary>
+    API_FIELD(Attributes="EditorOrder(71), EditorDisplay(\"Simulation\")")
+    bool EnableEnhancedDeterminism = false;
+
     /// <summary>
     /// The solver type to use in the simulation.
     /// </summary>
-    API_FIELD(Attributes="EditorOrder(72), EditorDisplay(\"Simulation\")")
+    API_FIELD(Attributes="EditorOrder(73), EditorDisplay(\"Simulation\")")
     PhysicsSolverType SolverType = PhysicsSolverType::ProjectedGaussSeidelIterativeSolver;
 
     /// <summary>