allocateGState()
Causes the view to maintain a private graphics state object, which encapsulates all parameters of the graphics environment.
Declaration
func allocateGState()Discussion
If you do not invoke allocateGState(), a graphics state object is constructed from scratch each time the NSView is focused.
The view builds the graphics state parameters using setUpGState(), then automatically establishes this graphics state each time the focus is locked on it. A graphics state may improve performance for view objects that are focused often and need to set many parameters, but use of standard rendering operators is normally efficient enough.
Because graphics states occupy a fair amount of memory, they can actually degrade performance. Be sure to test application performance with and without the private graphics state before committing to its use.