The basic state for the system's power supply.
Defined in SDL_power.h
typedef enum SDL_PowerState
{/**< cannot determine power status */
SDL_POWERSTATE_UNKNOWN, /**< Not plugged in, running on the battery */
SDL_POWERSTATE_ON_BATTERY, /**< Plugged in, no battery available */
SDL_POWERSTATE_NO_BATTERY, /**< Plugged in, charging battery */
SDL_POWERSTATE_CHARGING, /**< Plugged in, battery charged */
SDL_POWERSTATE_CHARGED } SDL_PowerState;