Mouse device constants, defined in Dinput.h, represent offsets within a mouse device's data packet, the DIMOUSESTATE or DIMOUSESTATE2 structure.
typedef enum Mouse_Device
{
DIMOFS_BUTTON0,
DIMOFS_BUTTON1,
DIMOFS_BUTTON2,
DIMOFS_BUTTON3,
DIMOFS_BUTTON4,
DIMOFS_BUTTON5,
DIMOFS_BUTTON6,
DIMOFS_BUTTON7,
DIMOFS_X,
DIMOFS_Y,
DIMOFS_Z,
} Mouse Device, *LPMouse Device;
The data at a given offset is associated with a device object (button or axis). Typically, these values are used in the dwOfs member of the DIDEVICEOBJECTDATA, DIOBJECTDATAFORMAT or DIDEVICEOBJECTINSTANCE structures.