I want to background-load scenes on a grid in another thread (seamless world style). While loading the PackedResource is easy and fast, the instancing of it is not. In another thread it takes up to half a minute to instance (not even adding to the tree) which is unacceptable. Instancing it from the main scene does take around 10ms which causes a visible frame stutter at 16 fps.
Note that due to other restrictions a decrease in complexity of the scene is not an option.
Is there a possibility to background load a scene in a sane way?
If not - why does instancing a scene takes so long in another thread and what is the engine dev team gonna do about that, as this would de-facto prevent making open world type games in a sane way without resorting to parsing and reconstructing scenes from pre-instanced nodes and textfiles as those can be used just fine in another thread.