/// <summary>
/// Update user activity metrics with data from a collection of skeletons.
/// </summary>
/// <param name="skeletons">
/// Collection of skeletons to use to update activity metrics.
/// </param>
/// <param name="timestamp">
/// Time when skeleton array was received for processing.
/// </param>
/// <remarks>
/// UserActivityMeter assumes that this method is called regularly, e.g.: once
/// per skeleton frame received by application, so if a user whose activity was
/// previously measured is now absent, activity record will be removed.
/// </remarks>
public void Update(ICollection<Skeleton> skeletons, long timestamp)
{
foreach (var skeleton in skeletons)
{
UserActivityRecord record;
if (this.activityRecords.TryGetValue(skeleton.TrackingId, out record))
{
record.Update(skeleton.Position, this.totalUpdatesSoFar, timestamp);
}
else
{
record = new UserActivityRecord(skeleton.Position, this.totalUpdatesSoFar, timestamp);
this.activityRecords[skeleton.TrackingId] = record;
}
}
// Remove activity records corresponding to users that are no longer being tracked
var idsToRemove = new List<int>();
foreach (var record in this.activityRecords)
{
if (record.Value.LastUpdateId != this.totalUpdatesSoFar)
{
idsToRemove.Add(record.Key);
}
}
foreach (var id in idsToRemove)
{
this.activityRecords.Remove(id);
}
++this.totalUpdatesSoFar;
}
/// <summary>
/// Gets the activity record associated with the specified user.
/// </summary>
/// <param name="userTrackingId">
/// Skeleton tracking Id of user associated with the activity record to
/// retrieve.
/// </param>
/// <param name="record">
/// [out] When this method returns, contains the record associated with the
/// specified user tracking Id, if the appropriate activity record is found.
/// This parameter is passed uninitialized.
/// </param>
/// <returns>
/// <code>true</code> if the UserActivityMeter contains an activity record
/// for the specified user tracking Id; otherwise, <code>false</code>.
/// </returns>
public bool TryGetActivityRecord(int userTrackingId, out UserActivityRecord record)
{
return this.activityRecords.TryGetValue(userTrackingId, out record);
}