using System; namespace PIANO2.Message { /// /// Represents the basic class for all MIDI short messages. /// /// /// MIDI short messages represent all MIDI messages except meta messages /// and system exclusive messages. This includes channel messages, system /// realtime messages, and system common messages. /// public abstract class ShortMessage : IMidiMessage { #region ShortMessage Members #region Constants public const int DataMaxValue= 127; public const int StatusMaxValue = 255; // // Bit manipulation constants. // private const int StatusMask = ~255; protected const int DataMask = ~StatusMask; private const int Data1Mask = ~65280; private const int Data2Mask = ~Data1Mask + DataMask; private const int Shift = 8; #endregion protected int msg = 0; #region Methods public byte[] GetBytes() { return BitConverter.GetBytes(msg); } internal static int PackStatus(int message, int status) { #region Require if(status < 0 || status > StatusMaxValue) { throw new ArgumentOutOfRangeException("status", status, "Status value out of range."); } #endregion return (message & StatusMask) | status; } internal static int PackData1(int message, int data1) { #region Require if(data1 < 0 || data1 > DataMaxValue) { throw new ArgumentOutOfRangeException("data1", data1, "Data 1 value out of range."); } #endregion return (message & Data1Mask) | (data1 << Shift); } internal static int PackData2(int message, int data2) { #region Require if(data2 < 0 || data2 > DataMaxValue) { throw new ArgumentOutOfRangeException("data2", data2, "Data 2 value out of range."); } #endregion return (message & Data2Mask) | (data2 << (Shift * 2)); } internal static int UnpackStatus(int message) { return message & DataMask; } internal static int UnpackData1(int message) { return (message & ~Data1Mask) >> Shift; } internal static int UnpackData2(int message) { return (message & ~Data2Mask) >> (Shift * 2); } #endregion #region Properties /// /// Gets the short message as a packed integer. /// /// /// The message is packed into an integer value with the low-order byte /// of the low-word representing the status value. The high-order byte /// of the low-word represents the first data value, and the low-order /// byte of the high-word represents the second data value. /// public int Message { get { return msg; } } /// /// Gets the messages's status value. /// public int Status { get { return UnpackStatus(msg); } } public abstract MessageType MessageType { get; } #endregion #endregion } }