Physics3D/Collider3D: Use btEmptyShape for NullCollider3D

Having no collider seems to break physics

include/Nazara/Physics3D/Collider3D.hpp

@@ -25,6 +25,7 @@ class btCollisionShape;
 class btConeShape;
 class btConvexHullShape;
 class btCylinderShape;
+class btEmptyShape;
 class btSphereShape;
 
 namespace Nz
@@ -179,8 +180,8 @@ namespace Nz
 	class NAZARA_PHYSICS3D_API NullCollider3D final : public Collider3D
 	{
 		public:
-			NullCollider3D() = default;
+			NullCollider3D();
-			~NullCollider3D() = default;
+			~NullCollider3D();
 
 			void BuildDebugMesh(std::vector<Vector3f>& vertices, std::vector<UInt16>& indices, const Matrix4f& offsetMatrix) const override;
 
@@ -188,6 +189,9 @@ namespace Nz
 
 			btCollisionShape* GetShape() const override;
 			ColliderType3D GetType() const override;
+
+		private:
+			std::unique_ptr<btEmptyShape> m_shape;
 	};
 
 	class NAZARA_PHYSICS3D_API SphereCollider3D final : public Collider3D

src/Nazara/Physics3D/Collider3D.cpp

@@ -18,6 +18,7 @@
 #include <BulletCollision/CollisionShapes/btConeShape.h>
 #include <BulletCollision/CollisionShapes/btConvexHullShape.h>
 #include <BulletCollision/CollisionShapes/btCylinderShape.h>
+#include <BulletCollision/CollisionShapes/btEmptyShape.h>
 #include <BulletCollision/CollisionShapes/btSphereShape.h>
 #include <Nazara/Physics3D/Debug.hpp>
 
@@ -371,6 +372,13 @@ namespace Nz
 
 	/********************************* NullCollider3D **********************************/
 
+	NullCollider3D::NullCollider3D()
+	{
+		m_shape = std::make_unique<btEmptyShape>();
+	}
+
+	NullCollider3D::~NullCollider3D() = default;
+
 	void NullCollider3D::BuildDebugMesh(std::vector<Vector3f>& /*vertices*/, std::vector<UInt16>& /*indices*/, const Matrix4f& /*offsetMatrix*/) const
 	{
 	}
@@ -382,7 +390,7 @@ namespace Nz
 
 	btCollisionShape* NullCollider3D::GetShape() const
 	{
-		return nullptr;
+		return m_shape.get();
 	}
 
 	ColliderType3D NullCollider3D::GetType() const