Abstract: Disclosed herein are related to a system, a method, and a non-transitory computer readable medium for controlling a central plant. In one aspect, the system obtains a control envelope for a device controlled by the controller. The control envelope comprises boundaries of a plurality of control regions in a multidimensional operating space for the device. Each control region is enclosed by a corresponding boundary. The system counts a number of times that a ray of the device crosses the boundary of a control region. The system determines whether an operating point of the device is within the control region based on the counted number. The system operates the device according to a predetermined control technique corresponding to the control region, in response to determining that the operating point of the device is within the control region.