List<Primitive> primitives = new ArrayList<>();
primitives.add(new PlaneXZ(-halfWidth, halfWidth, -halfDepth, halfDepth, halfHeight, Vector3f.Y)); //top face
primitives.add(new PlaneXZ(-halfWidth, halfWidth, -halfDepth, halfDepth, -halfHeight, Vector3f.Y.negated())); //bottom face
primitives.add(new PlaneXY(-halfWidth, halfWidth, -halfHeight, halfHeight, -halfDepth, Vector3f.Z)); //front face
primitives.add(new PlaneYZ(-halfHeight, halfHeight, -halfDepth, halfDepth, -halfWidth, Vector3f.X.negated())); //left face