private void Overlay_NewPackets(object sender, InkCollectorNewPacketsEventArgs e)
{
/*** THIS ROUTINE MUST BE EXTREMELY FAST ***/
/*
* Since we are handling a flurry of packet
* data, this routine should not perform any
* significant processing, just data recording.
*
* Asynchronous invocation on the windows forms
* thread is used to delay as much sample
* processing as possible.
*/
//go over the packet data and store InkSamples
int[] PacketData = e.PacketData;
if (PacketData[2] == 0) //new stroke since timer is 0; use the internal timer to compute the time of the first packet
{
//check if the packets have pressure data
Tablet CurrentTablet = e.Cursor.Tablet;
Overlay_NewPackets_PacketsHavePressure = CurrentTablet != null &&
CurrentTablet.IsPacketPropertySupported(PacketProperty.NormalPressure);
//raise the NewInkSample event with an invalid ink sample to signal a new stroke to listeners
_Overlay.AttachedControl.BeginInvoke(new NewRawInkSampleHandler(OnNewRawInkSample), new RawInkSample(_Timer.Now()));
}
for (int i = 0; i < PacketData.Length;)
{
RawInkSample s = new RawInkSample();
s.Time = _Timer.Now();
s.X = PacketData[i++];
s.Y = PacketData[i++];
i++; //skip the timer sample
s.Pressure = Overlay_NewPackets_PacketsHavePressure ? PacketData[i++] : 0;
//have the form thread raise the NewInkSample event at its convenience
_Overlay.AttachedControl.BeginInvoke(new NewRawInkSampleHandler(OnNewRawInkSample), s);
}
}