Returns information about the player's mana/energy/etc regeneration rate. Contexts for inactiveRegen and activeRegen vary by power type.

If the player (currently) uses mana, activeRegen refers to mana regeneration while casting (within five seconds of casting a spell) and inactiveRegen refers to mana regeneration while not casting (more than five seconds after casting a spell). For other power types, activeRegen refers to regeneration while in combat and inactiveRegen to regeneration outside of combat.

Note that values returned can be negative: e.g. for rage and runic power users, inactiveRegen describes the rate of power decay while not in combat.