Add Jolt Physics as an alternative 3D physics engine

Co-authored-by: Jorrit Rouwe <jrouwe@gmail.com>

thirdparty/jolt_physics/Jolt/Physics/PhysicsUpdateContext.cpp

@@ -0,0 +1,23 @@
+// Jolt Physics Library (https://github.com/jrouwe/JoltPhysics)
+// SPDX-FileCopyrightText: 2021 Jorrit Rouwe
+// SPDX-License-Identifier: MIT
+
+#include <Jolt/Jolt.h>
+
+#include <Jolt/Physics/PhysicsUpdateContext.h>
+
+JPH_NAMESPACE_BEGIN
+
+PhysicsUpdateContext::PhysicsUpdateContext(TempAllocator &inTempAllocator) :
+	mTempAllocator(&inTempAllocator),
+	mSteps(inTempAllocator)
+{
+}
+
+PhysicsUpdateContext::~PhysicsUpdateContext()
+{
+	JPH_ASSERT(mBodyPairs == nullptr);
+	JPH_ASSERT(mActiveConstraints == nullptr);
+}
+
+JPH_NAMESPACE_END