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This is a follow-up to yesterday's codereview-question about reading serial data and parsing it.

The code below is run into a seperate thread looped endlessly. Currently I track the position in my inputBufer manually and copy all bytes which haven't been processed into a new byte-array and assigning that to the old inputBuffer.

Can the read buffer handling be improved?

bytesRead = SerialPort.Read(inputBuffer, bufferPos, SerialPort.BytesToRead);
bufferPos += bytesRead;
bytesProcessed = 0;
// process data-packets
for (int i = 0; i < this.bufferPos; i++) {
 // Flex sensor data
 //
 if (this.bufferPos-i >= 14 && inputBuffer[i] == 'F'){
 i++;
 short[] sensorData = new short[6];
 sensorData[0] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // thumb
 sensorData[1] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // index finger (finger knuckle)
 sensorData[2] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // middle finger
 sensorData[3] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // ring finger
 sensorData[4] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // not used
 sensorData[5] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // index finger (hand knucke)
 // checksum
 byte checksum = inputBuffer[i++];
 ParseSerialData(PacketType.Flex, sensorData, checksum);
 bytesProcessed = i;
 //Debug.Log (sensorData[0] + " then " + bytesProcessed);
 }
 // Raw sensor data
 //
 if (this.bufferPos-i >= 20 && inputBuffer[i] == 'S'){
 i++;
 short[] sensorData = new short[9];
 sensorData[0] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // gyroscope X
 sensorData[1] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // gyroscope Y
 sensorData[2] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // gyroscope Z
 sensorData[3] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // accelerometer X
 sensorData[4] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // accelerometer Y
 sensorData[5] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // accelerometer Z
 sensorData[6] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // magnetometer X
 sensorData[7] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // magnetometer Y
 sensorData[8] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // magnetometer Z
 // checksum
 byte checksum = inputBuffer[i++];
 ParseSerialData(PacketType.Raw, sensorData, checksum);
 bytesProcessed = i;
 }
 // Quaternion of device's rotation
 //
 if (this.bufferPos-i >= 20 && inputBuffer[i] == 'Q'){
 i++;
 short[] sensorData = new short[4];
 sensorData[0] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // W
 sensorData[1] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // X
 sensorData[2] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // Y
 sensorData[3] = (short)((short)inputBuffer[i++] << 8 | inputBuffer[i++]); // Z
 // checksum
 byte checksum = inputBuffer[i++];
 ParseSerialData(PacketType.Quaternion, sensorData, checksum);
 bytesProcessed = i;
 }
}
// Copy unprocessed rest of stream
int rest = bufferPos - bytesProcessed;
 if (rest > 0){
 byte[] tempBuffer = new byte[4096];
 Array.Copy (inputBuffer, bytesProcessed, tempBuffer, 0, rest);
 inputBuffer = tempBuffer;
 bufferPos = rest;
}
else {
 inputBuffer = new byte[4096];
 bufferPos = 0;
}