DirectInput Device Data

This section covers the following basic concepts of getting data from DirectInput devices.

• Buffered and Immediate Data
• Time Stamps and Sequence Numbers
• Polling and Event Notification
• Relative and Absolute Axis Coordinates

The following topics describe specific details about output data and mouse, keyboard, and joystick input data.

• Mouse Data
• Keyboard Data
• Joystick Data
• Output Data

DirectInput provides two mechanisms for identifying data retrieved from devices. Using the traditional mechanism, the application identifies the data as coming from a particular device object, such as a the x-axis on a mouse or the F1 key on a keyboard. With the newer system, available for the first time in DirectX 8.0, DirectInput associates application-defined values (for instance, identifiers for particular game actions such as moving or shooting) with the most suitable device objects available. When data is retrieved, the application does not concern itself with the actual device or device object from which the data comes. It acts only on the meaning of that data.

Most of the information in this section applies to both mechanisms. For more information about the newer way of identifying device data, see Action Mapping.