Controller

A controller is the method BetterDisplay uses to read or change a device's controls. Examples include Apple's native display interfaces, DDC commands, network-device protocols and software image processing.

One display can use different controllers for different operations. For example, brightness may use DDC while audio volume uses a macOS audio device. A supported connection or an enabled controller does not guarantee that every operation is available.

Hardware controllers request device changes; software controllers change the presented image. A combined brightness control can bring more than one method together. See Device Control and Brightness.