Currently, the rendering behavior of SK is as follows:

• Always render frames as quickly as possible, or as limited by vsync (whichever is lower)

The feature request is to behave in the following way (identical to a major mmo):

• With game window focus: render frames as as quickly as possible, up to some rate 'maxfps' or as limited by vsync (whichever is lower)
• Without game window focus: render frames as quickly as possible, up to some rate 'maxfpsbk' or as limited by vsync (whichever is lower)
• With game window minimized: disable rendering thread or equivalent (null rendering, buffer copy)

While there may be technical reasons why the last condition might not be possible (such as the game runs entirely in one thread and there is no simple way to decouple rendering or implement null rendering), there should be no cogent technical reasons why the first two could not be simply added.

The reason for the request is for system performance. The game can currently monopolize a modern cpu core and it may be unnecessary or undesired.