Q3Tracker_GetPosition
You can use theQ3Tracker_GetPosition
function to get the position of a tracker.
TQ3Status Q3Tracker_GetPosition ( TQ3TrackerObject trackerObject, TQ3Point3D *position, TQ3Vector3D *delta, TQ3Boolean *changed, unsigned long *serialNumber);
trackerObject
- A tracker object.
position
- On exit, the current position of the specified tracker.
delta
- On exit, the change in position since the last call to
Q3Tracker_GetPosition
.changed
- On exit, a Boolean value that indicates whether the
position
ordelta
parameter was changed (kQ3True
) or not (kQ3False
).serialNumber
- On entry, a tracker serial number, or
NULL
. On output, the current tracker serial number.DESCRIPTION
TheQ3Tracker_GetPosition
function returns, in theposition
parameter, the current position of the tracker specified by thetrackerObject
parameter. In addition, it can return, in thedelta
parameter, the relative change in position since the previous call toQ3Tracker_GetPosition
.On entry, if the value of
delta
isNULL
, the relative contribution is combined into the reported position. If the value ofdelta
is notNULL
, thendelta
is set to the relative motion that has been accumulated since the previous call toQ3Tracker_GetPosition
. In either case, the position accumulator is set to (0, 0, 0) by this function.If the value of the
serialNumber
parameter isNULL
,Q3Tracker_GetPosition
fills in theposition
anddelta
parameters and returns the valuekQ3True
in thechanged
parameter. Otherwise, the value specified in theserialNumber
parameter is compared with the tracker's current serial number. If the two serial numbers are identical,Q3Tracker_GetPosition
leaves the two coordinate parameters and theserialNumber
parameter unchanged and returns the valuekQ3False
in thechanged
parameter. If the two serial number differ,Q3Tracker_GetPosition
fills in the two coordinate parameters, updates theserialNumber
parameter, and returns the valuekQ3True
in thechanged
parameter.If the specified tracker is inactive, then the
position
parameter is set to the point (0, 0, 0), thedelta
parameter is set to (0, 0, 0) if it is non-NULL
, and thechanged
parameter is set tokQ3False
if it is non-NULL
.
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