Fix issue with filters being ignored for two controllers colliding

Source/Engine/Physics/Colliders/CharacterController.cpp

@@ -173,6 +173,7 @@ CharacterController::CollisionFlags CharacterController::Move(const Vector3& dis
         filters.mFilterData = (PxFilterData*)&_filterData;
         filters.mFilterCallback = Physics::GetCharacterQueryFilterCallback();
         filters.mFilterFlags = PxQueryFlag::eDYNAMIC | PxQueryFlag::eSTATIC | PxQueryFlag::ePREFILTER;
+        filters.mCCTFilterCallback = Physics::GetCharacterControllerFilterCallback();
 
         result = (CollisionFlags)(byte)_controller->move(C2P(displacement), _minMoveDistance, deltaTime, filters);
         _lastFlags = result;

Source/Engine/Physics/Physics.Queries.cpp

@@ -6,6 +6,8 @@
 #include "Actors/PhysicsColliderActor.h"
 #include <ThirdParty/PhysX/PxScene.h>
 #include <ThirdParty/PhysX/PxQueryFiltering.h>
+#include <ThirdParty/PhysX/PxRigidDynamic.h>
+#include <ThirdParty/PhysX/characterkinematic/PxController.h>
 
 // Temporary result buffer size
 #define HIT_BUFFER_SIZE	128
@@ -217,6 +219,52 @@ public:
     }
 };
 
+class CharacterControllerFilter : public PxControllerFilterCallback
+{
+private:
+
+    PxShape* getShape(const PxController& controller)
+    {
+        PxRigidDynamic* actor = controller.getActor();
+
+        // Early out if no actor or no shapes
+        if (!actor || actor->getNbShapes() < 1)
+            return nullptr;
+
+        // Get first shape only.
+        PxShape* shape = nullptr;
+        actor->getShapes(&shape, 1);
+
+        return shape;
+    }
+
+public:
+
+    bool filter(const PxController& a, const PxController& b) override
+    {
+        // Early out to avoid crashing
+        PxShape* shapeA = getShape(a);
+        if (!shapeA)
+            return false;
+
+        PxShape* shapeB = getShape(b);
+        if (!shapeB)
+            return false;
+
+        // Let triggers through
+        if (PxFilterObjectIsTrigger(shapeB->getFlags()))
+            return false;
+
+        // Trigger the contact callback for pairs (A,B) where the filtermask of A contains the ID of B and vice versa
+        const PxFilterData shapeFilterA = shapeA->getQueryFilterData();
+        const PxFilterData shapeFilterB = shapeB->getQueryFilterData();
+        if (shapeFilterA.word0 & shapeFilterB.word1)
+            return true;
+
+        return false;
+    }
+};
+
 PxQueryFilterCallback* Physics::GetQueryFilterCallback()
 {
     static QueryFilter Filter;
@@ -229,6 +277,12 @@ PxQueryFilterCallback* Physics::GetCharacterQueryFilterCallback()
     return &Filter;
 }
 
+PxControllerFilterCallback* Physics::GetCharacterControllerFilterCallback()
+{
+    static CharacterControllerFilter Filter;
+    return &Filter;
+}
+
 bool Physics::RayCast(const Vector3& origin, const Vector3& direction, const float maxDistance, uint32 layerMask, bool hitTriggers)
 {
     // Prepare data

Source/Engine/Physics/Physics.h

@@ -112,6 +112,11 @@ DECLARE_SCRIPTING_TYPE_NO_SPAWN(Physics);
     /// </summary>
     static PxQueryFilterCallback* GetCharacterQueryFilterCallback();
 
+    /// <summary>
+    /// Gets the default controller filter callback used for the character controller collisions detection.
+    /// </summary>
+    static PxControllerFilterCallback* GetCharacterControllerFilterCallback();
+
     /// <summary>
     /// Gets the default physical material.
     /// </summary>

Source/Engine/Physics/Types.h

@@ -39,6 +39,7 @@ namespace physx
     class PxController;
     class PxCapsuleController;
     class PxQueryFilterCallback;
+    class PxControllerFilterCallback;
     class PxHeightField;
     struct PxFilterData;
     struct PxRaycastHit;