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Currently, when immediately compile shaders is not enabled, the ubershaders will be placed before any specialized shaders in the compile queue in hybrid ubershaders mode. This means that Dolphin could potentially use the ubershaders for a longer time than it would have if we blocked startup until all shaders were compiled, leading to a drop in performance.
- In D3D, shaders could be compiled on the main thread, blocking startup. - Reduced the latency between a pipeline being requested and used in all backends in hybrid ubershader mode, when no shader stages were present. - Fixed a case where async compilation could cause the same UID to be appended multiple times to the UID cache. - Fix incorrect number of threads being used when immediately compile shaders was enabled.
Same behavior, simpler code.
As this just hands off the arguments to another type's constructor, perfect forwarding should be used here to preserve any potential move semantics.
At runtime, we only really want a single shader compiler thread. However, for initial boots, we can use a higher number to speed things up.