private int readFromOffset(int offset, byte[] rawData)
{
// the first 2 bytes are the version - discard it for now
int frameTypeAndSequence = rawData[offset + 2];
int frameType = frameTypeAndSequence & 3;
int sequence = frameTypeAndSequence >> 2;
int frameLength = 0;
if (frameType == 0)
{
telemPacketCount++;
if (telemPacketCount > packetCountAtStartOfNextRateCheck)
{
lastPacketRateEstimate = (int)((float)TimeSpan.TicksPerSecond * (float)(telemPacketCount - packetCountAtStartOfCurrentRateCheck) / (float)(DateTime.UtcNow.Ticks - ticksAtStartOfCurrentPacketRateCheck));
Console.WriteLine("Packet rate = " + lastPacketRateEstimate + "Hz, totals: type0 = " + telemPacketCount + " type1 = " + stringsPacketCount + " type2 = " + additionalStringsPacketCount +
" in sequence = " + inSequenceTelemCount + " oos accepted = " + acceptedOutOfSequenceTelemCount + " oos rejected = " + discardedTelemCount);
packetCountAtStartOfCurrentRateCheck = telemPacketCount;
packetCountAtStartOfNextRateCheck = packetCountAtStartOfCurrentRateCheck + packetRateCheckInterval;
ticksAtStartOfCurrentPacketRateCheck = DateTime.UtcNow.Ticks;
}
frameLength = sTelemetryData_PacketSize;
Boolean sequenceCheckOK = isNextInSequence(sequence);
if (sequenceCheckOK)
{
inSequenceTelemCount++;
}
if (strictPacketOrdering && !sequenceCheckOK)
{
discardedTelemCount++;
}
else
{
GCHandle handle = GCHandle.Alloc(rawData.Skip(offset).Take(frameLength).ToArray(), GCHandleType.Pinned);
try
{
sTelemetryData telem = (sTelemetryData)Marshal.PtrToStructure(handle.AddrOfPinnedObject(), typeof(sTelemetryData));
if (sequenceCheckOK || !telemIsOutOfSequence(telem))
{
buttonsState = ConvertBytesToBoolArray(telem.sDPad, telem.sJoyPad1, telem.sJoyPad2);
lastSequenceNumberForTelemPacket = sequence;
workingGameState = StructHelper.MergeWithExistingState(workingGameState, telem);
newSpotterData = workingGameState.hasNewPositionData;
}
}
finally
{
handle.Free();
}
}
}
else if (frameType == 1)
{
stringsPacketCount++;
frameLength = sParticipantInfoStrings_PacketSize;
GCHandle handle = GCHandle.Alloc(rawData.Skip(offset).Take(frameLength).ToArray(), GCHandleType.Pinned);
try
{
sParticipantInfoStrings strings = (sParticipantInfoStrings)Marshal.PtrToStructure(handle.AddrOfPinnedObject(), typeof(sParticipantInfoStrings));
workingGameState = StructHelper.MergeWithExistingState(workingGameState, strings);
}
finally
{
handle.Free();
}
}
else if (frameType == 2)
{
additionalStringsPacketCount++;
frameLength = sParticipantInfoStringsAdditional_PacketSize;
GCHandle handle = GCHandle.Alloc(rawData.Skip(offset).Take(frameLength).ToArray(), GCHandleType.Pinned);
try
{
sParticipantInfoStringsAdditional additional = (sParticipantInfoStringsAdditional)Marshal.PtrToStructure(handle.AddrOfPinnedObject(), typeof(sParticipantInfoStringsAdditional));
workingGameState = StructHelper.MergeWithExistingState(workingGameState, additional);
}
finally
{
handle.Free();
}
}
else
{
Console.WriteLine("Unrecognised frame type " + frameType + " from byte " + rawData[offset + 2]);
}
return(frameLength + offset);
}
public static pCarsAPIStruct MergeWithExistingState(pCarsAPIStruct existingState, sParticipantInfoStringsAdditional udpAdditionalStrings)
{
int offset = udpAdditionalStrings.sOffset;
if (existingState.mParticipantData == null)
{
existingState.mParticipantData = new pCarsAPIParticipantStruct[56];
}
for (int i = offset; i < offset + 16 && i < existingState.mParticipantData.Length; i++)
{
existingState.mParticipantData[i].mName = udpAdditionalStrings.sName[i - offset].nameByteArray;
}
return(existingState);
}