Some specific paks are loaded through code (common.rpak, ui.rpak. etc). We have implemented a system that also loads 2 common rpaks that are of our own (common_sdk.rpak and ui_sdk.rpak).
There is al additional syustem we had implemented earlier that allows you to mount rpaks during level load, which will get loaded before the actual level rpak, this is useful as when we port a map that has evolved slightly from its original one, only needing 20 new models, it makes more sense to load the original rpak + a new one that contains the 20 new models to save disk space.
This is also useful for mounting paks specific to mods for a certain map, however since we have some core mods (flowstate) we have to add it to the settings for for each level. These paks also get dropped and reloaded each time on level changes causing longer load times and more memory usage during level loads.
This system mounts paks after all common paks are loaded (from both the engine and sdk), and keeps them active just like the common paks throughout level changes until they are either manually unloaded, or the game has been closed.
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