Microsoft's DirectWrite font renderer, which has been the default since Windows 7 IIRC: https://docs.microsoft.com/en-us/windows/win32/directwrite/d...

Its a blackbox. But Microsoft is very clear that its "hardware accelerated", whatever that means (IE: I think it means they got GPU-shaders handling a lot of details).

GDI / etc. etc. are legacy. You were supposed to start migrating towards Direct2D and DirectWrite decades ago. Cleartype itself moved to DirectWrite (though it still has GDI renderer for legacy purposes).

https://docs.microsoft.com/en-us/windows/win32/directwrite/i...